Category Archives: Uncategorized
By Fleur van Griensven
When a girl tells people she just started lifting, they often think that she will wake up as a Hulk the next day. They think that lifting makes women look bulky, so they shouldn’t train like men. Another thing you often hear, is that women can never get as big as men, but is that true? Do women naturally have less muscular potential than men? Or can we finally acknowledge the fact that women should train heavy too and that a lot of girls are not living up to their potential by lifting 2 kg pink dumbbells?
The natural muscular potential of women.
Popular opinion is that men have more muscular potential than women and thus can gain more muscle. However, some research indicates that women naturally have roughly the same muscle building potential. A prospective intervention study examined the influences of gender on muscle size responses to strength training. The results were that women can gain the same percentage of muscle mass compared to men during strength training .
Studies on protein synthesis came also to the same conclusion. Women have similar muscle protein synthesis rates and thus seem to build the same amount of muscle protein after training compared to men . This is however the conclusion of only a few studies, so more research is definitely needed to be 100% clear that women do naturally have the same muscle building potential. However, this is difficult because these studies take a long time and need to be well-controlled.
When women start training they do have a different body composition. Most of the times, women have less muscle mass and more fat mass compared to men. Women have +/- 12% essential body fat compared to just +/- 3% fat in men . Essential body fat is all the fat which we can not lose without it negatively affecting our physiological functions. It surrounds our organs and nerve tissues. Men and women do have a different starting point when it comes to muscle mass, but they seem to be gaining muscle mass at the same rate. Keep in mind that for the rest of this article I always compare men with a starting point to women with the same starting point, so a same body composition.
How about testosterone?
Testosterone is the most important male sex hormone. Women however do also produce testosterone, even though they have 15 times less active testosterone than men, under normal circumstances . Besides the known functions of testosterone in our body, like development of primary/secondary sexual characteristics and production of sperm, it also plays a positive role in muscle building. Testosterone is an anabolic hormone, which means that it stimulates muscle protein synthesis and thus muscle growth.
Is it then true, because women have less testosterone they also have less potential to build muscle mass? No, this is probably not the case. The testosterone functions are different in men and women. What comes next might be a bit of a complicated story with terms you never heard about, but do not worry about that and try to see the big picture in why having less testosterone as a woman is not that bad at all.
It seems that testosterone is not needed for muscle development in women because growth factors like IGF-1 and growth hormone take over the anabolic role that testosterone plays in men . This has been found in an animal study done with mice, so more studies are necessary to test if this is the case in humans too. However since women can gain muscle with lower testosterone levels, it can be safely assumed that other hormones besides testosterone are involved in this muscle building process.
Women have just as much IGF-1 and produce +/- 3 times as much growth hormone as men . This study shows that despite the fact that women have lower testosterone levels than men, they do have higher growth hormone levels. It could be possible that in women growth hormone partly takes over the role of testosterone. This explains why having less testosterone does probably not limit how much muscle women can build. People think that testosterone is the most important hormone, but there are more hormones that play a role in muscle growth.
The other (sex)hormones combined with the advantages/disadvantages women have.
Where testosterone is the most important male sex hormone, estrogen is the most important female sex hormone. Estrogen is commonly seen as the hormone that makes you fat and frail. However, its positive effects should not be disregarded. Some of these positive physiological effects are:
- It is anti-catabolic, which means that it prevents muscle loss .
- It aids in muscle repair .
- It is good for connective tissue (bones, ligaments etc.).
The bad reputation of estrogen is based on nothing more than the assumption that if testosterone is anabolic, estrogen must be catabolic. There is a lot of ongoing research and there are indications that it plays a role in muscle growth and the well-being of skeletal muscle. However, more research is needed in the future.
One big disadvantage for a lot of women these days is the use of the anti-contraceptive pill. This holds especially true for the ones containing a lot of progesterone. They do have a negative effect on muscle growth compared to not using an anti-contraceptive pill, because progesterone competes with testosterone for the androgen receptor. Basically, this comes down to less active testosterone when you take in an anti-contraceptive pill with a lot of progesterone . How much of a negative effect occurs is hard to tell, because it is very difficult to study.
Here is a practical tip which you can use to take advantage of the benefit we have being a woman. Hopefully this and more research in the future about some other topics relating the effects of hormones on muscle growth will help you get the most out of your training sessions!
- We can use a higher rep range.
There are two types of muscle fibres: Type I&II. Type I muscle fibers are known as slow-twitch muscle fibers, which makes them able to contract for a long period of time and more resistant to fatigue. Being able to contract for a long period of time could mean that women can benefit from a higher rep range. This could mean that for women to grow to their full potential, more reps per set need to be done to benefit from the type I fibres which are more resistant to fatigue and can contract longer. One study came to the conclusion that during exercise in women, a potential conversion to type I muscle fibers or no conversion at all takes place . This study looked at the muscle fibre adaptations during execution of a knee-extension exercise in both young men and women. They found a significant increase in percentage of type I fibres in young women. The study has its limitations: if the muscle fibres had been splitted into type Ia, IIa, IIb etcetera, no significant result would have been found. This also is anecdotal evidence and more research needs to be done.
Conclusion, do women naturally have less muscle building potential than men?
There is some research which indicates that women can gain the same percentage of muscle mass compared to men during strength training [1,2]. However more research is needed.
Why you see more men with a significant amount of muscle mass compared to women and why women aren’t 100% living up to their potential can be contributed to a lot of factors:
- Mostly social-cultural. There are not as many women compared to men training with weights. If they do train, some of them just do not want to build as much mass as possible. Everyone has their own goal and idea of how they want to look. That is okay, as long as you do what makes you happy and never have someone telling you what you shouldn’t or can’t achieve.
- If women go to the gym, they spend countless hours on the treadmill or playing around with pink dumbbells, that is for sure not 100% optimal if you want to build as much muscle mass as possible.
- Oral-contraceptives, which have a negative effect on muscle growth. Part of the anabolic role of testosterone will be taken over by other hormones in women, so testosterone production probably does not limit how much muscle women can build.
More information about this topic for sure will come available in the future as more and more studies are being done on this interesting topic. When that time comes we will update this article and bring you the latest conclusions.
One take home message for all the women out there busting their ass off (or on) in the gym: you probably are not less capable of putting on muscle mass than men, and the only limitations you have are the ones you put on yourself!
 Roth, SM (2001). Muscle size responses to strength training in young and older men and women. Journal of the American Geriatrics Society, 49(11), 1428-33.
 O’Hagan, FT (1995). Response to resistance training in young women and men. International journal of sports medicine, 16(5), 314-21.
 Vehrs, P (2013). Assessment and interpretation of body composition in physical education. Journal of Physical Education, Recreation & Dance, 46-51
 Wisse, B (2016, 2 March). Testosterone. Retrieved from https://medlineplus.gov/ency/article/003707.htm
 MacLean, HE (2008). Impaired skeletal muscle development and function in male, but not female, genomic androgen receptor knockout mice. FASEB journal, 22(8), 2676-89.
 Van den Berg, G (1996). An amplitude-specific divergence in the pulsatile mode of growth hormone (GH) secretion underlies the gender difference in mean GH concentrations in men and premenopausal women. Journal Clinical endocrinal Metab, 81(7), 2460-2467
 Hansen, Mette (2014). Influence of Sex and Estrogen on Musculotendinous Protein Turnover at Rest and after exercise. Exercise & Sport Sciences Reviews, 42(4), 183-192.
 Velders, M (2013). How Sex hormones promote skeletal muscle regeneration. Sports Medicine, 43(11), 1089-1100.
 Woock, C (2009). Oral Contraceptive use impairs muscle gains in young women. The FASEB Journal, 23(1).
 Martel, G (2006). Age and sex affect human muscle fibre adaptations to heavy resistance strength training. Experimental Physiology, 91(2), 457-464
By Fleur van Griensven
BCAA’s are thought to put you in an anabolic state. Some people claim that you should use them before training when you are in a fasted state to prevent muscle loss. Is this true and should we all run to the nearest shop to spare our gains? Or is it just a smart marketing strategy from producing companies?
What are BCAA’s?
BCAA’s are branched-chain amino acids. These amino acids are branched (in Dutch vertakt), which in comparison to other amino acids makes it easier for enzymes to digest. Amino acids are the building blocks of proteins. When we consume protein our body uses specific enzymes which breaks these down into smaller units, the amino acids. There are 20 amino acids which can be converted into one another. At least, that’s true for the non-essential ones. The essential amino acids need to be present in our food because the body can’t synthesize them itself. There are 8 essential amino acids: Lysine, Tryptophan, Phenylalanine, Leucine, Isoleucine, Threonine, Methionine and Valine.
The three BCAA’s are Leucine, Isoleucine and Valine. During intensive activity, muscles will convert these quickly into energy. BCAA’s are supplemented just before or during training. The reason for supplementation is to stop muscle breakdown, recover quicker and in the long run build more muscle mass and strength. 
Are BCAA’s useful?
Many studies have been done on BCAA’s. A lot of people claim that you should take them before training fasted or during training. Some studies do find an effect of supplementation, whilst others don’t. There are many promising abstracts, but they are almost always hampered by lack of dietary control and/or a low protein intake. Making real conclusions based on these studies is hard.
The effectiveness of BCAA supplementation to reduce exercise-induced muscle soreness is mixed. One randomized placebo controlled study compared a BCAA’s + carbohydrate versus a carbohydrate sports drink following 3 days of intense weight training. BCAA + carbohydrate supplementation did not improve markers of muscle damage/soreness compared to carbohydrates only. 
A randomized, double-blind, placebo controlled study concluded the opposite. Participants received a BCAA supplement or a placebo. Before and after the damaging exercise (100 drop-jumps) they measured different muscle damage variables. They concluded that BCAA administered before and following damaging resistance exercise reduces markers of muscle damage and accelerates recovery in resistance-trained males. This might be due to greater bioavailability of substrate to improve protein synthesis. 
Research which shows a net anabolic effect of BCAA supplementation before, during or after training is often used to sell these powders . Supplementing BCAA’s would eventually increase build-up of muscle. No evidence supports that ingestion of BCAA supplements is more effective than consuming a proper amount of food (protein) with respect to building muscle. In fact, there’s research to the contrary: food, and whey protein specifically, may be even more effective than a BCAA drink . This is why you can consume a whey shake before training to get into a net anabolic state. It’s cheaper than BCAA powders, comes in many delicious flavours and is more effective.
What are the costs of BCAA’s?
BCAA’s can be bought in shops and online. The prices differ per brand and they sell both powders as tablets. For example, BCAA’s from Body & Fitshop will cost you €14,90 for 500 grams. The recommended daily serving is 20 grams before or during training, so a package lasts for about 25 days. Thus, quite expensive.
The amino acids shown in the picture above (Amino X from BSN) are even more expensive. You pay €19,90 for 435 grams. The daily serving is 29 grams, so you would pay €1,33 on a daily. Are these any better than Body & Fitshop own label? They both contain the three amino acids L-leucine, L-isoleucine and L-valine but probably in a bit different ratio. The Amino X also contains L-alanine, Taurine and L-arginine and vit D3 + vit B6. Will this add any effect to the product itself? Not sure, but you will just pay for something extra next to the BCAA’s you actually want to buy.
Selling BCAA’s on the market is a smart marketing strategy, because you basically pay for only three amino acids with a bit of a nice flavour added to it. Companies make good use of this by slogans as: ‘Amino X BSN, next level technology!’ or ‘BCAA Sensation V2 only contains the perfect ratio amino acids’. Yeah right if this would all be true, would just not one product with everything be enough? Companies try to come up with new things to make us consumers think that we just have to buy the new product. Smart marketing strategy it is!
Conclusion, BCAA’s: a smart marketing strategy?
Concluded can be so far:
- The studies find a mixed effect of supplementation, but if they do find an effect are lacking in many aspects.
- They are a smart marketing strategy.
- They are expensive.
- You can get your BCAA’s from food instead which is cheaper and more satisfying.In general, there are studies that seem to show promising effects of supplementation. These however are hampered when taking a closer look. A whey shake just before training has shown to be even more effective in provoking a net anabolic response.
If you think that you need to take a serving of BCAA’s before training fasted, first ask yourself the following. Is training fasted going to be any better in losing fat than having a meal and smash the hell out of your cardio session? An article about fasted morning cardio might follow, but at the end of the day it still comes down to being in a negative energy balance. If you enjoy doing cardio first thing in the morning go ahead, but don’t get deceived by this BCAA marketing strategy, drink a whey shake and save yourself money!
 BCAA. Retreived from: http://www.eigenkracht.nl/supplementen/specifieke-supplementen/bcaa
 Wesley C. Kephart et all (2016). Post-exercise branched chain amino acid supplementation does not affect recovery markers following three consecutive high intensity resistance training bouts compared to carbohydrate supplementation. Journal of the International Society of Sports Nutrition.
 Glyn Howatson et all (2012). Exercise-induced muscle damage is reduced in resistance-trained males by branched chain amino acids: a randomized, double-blind, placebo controlled study. Journal of the International Society of Sports Nutrition
 Sharp CP, Pearson DR (2010). Amino acid supplements and recovery from high-intensity resistance training. Journal Strength Conditioning Research.
 Hulmi JJ et all (2010). Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutrition & Metabolism.
By Wietse In het Panhuis
Probably everyone recognizes this situation: You have had a busy work week, waking up early at 7 am every morning, and going to bed at 11 pm. On Friday, you feel tired and you have the feeling that you should catch up on sleep, but you also want to go to bed later, since it’s weekend. Therefore, you decide not to set your alarm clock on Saturday and Sunday. You stay up late on Friday and Saturday, and you wake up at 11 am on Saturday and Sunday morning. Is this a good idea? Does sleeping in really help to catch up on sleep, rest and recover?
As mentioned before in my other article on sleep and rest, there is not an optimal sleep duration that works for all people (if you missed the previous article, you can read it here: https://wageningenbeasts.com/2016/12/04/optimizing-your-sleep-and-biological-rhythm/). Some people need much sleep, others need less. The reason for this is differences in habit, but also differences in genetics (and of course differences in age, but this can be neglected since the readers of this article are probably all students). Therefore, no solid recommendations can be done on how long you should sleep.
If you get less sleep than you need, sleep deprivation (the need for sleep) will accumulate. Often when you have one bad night of sleep, you will still feel fine the next day, but when this happens for a few nights in a row you will start to notice the effects of sleep deprivation. Of course I don’t have to explain to you that (chronic) sleep deprivation is bad for you and can have serious health consequences. That is probably also the reason you want to sleep late during the weekends, to get some more rest. In theory, it is true that the body needs to catch up on sleep when it is sleep deprived, so in that respect you are right. There are however other factors that play a role.
The biological clock
Like mentioned before in my previous article, the biological clock is a mechanism that (a.o.) informs the body about time: the sensation of day and night. The biological clock is a complex system, because it can be influenced by many factors (think of light, psychological factors, activity, food intake). The complexity is also the reason why the biological clock does not adapt easily to changes in the daily routine. A jet-lag is a perfect example for this. After traveling it takes some time to adjust the sleep rhythm to the new time zone. However, it takes even longer before you are fully adapted to the new time (e.g. when you don’t need an alarm clock to wake up at a certain time). A rule of thumb is: don’t mess with your biological clock! It is best for the biological clock to have a regular pattern in sleep (most important), but also in things like food intake. Big changes in these patterns disturb the clock, which could result in sleeping problems, fatigue, changes in mood, concentration, study performance and metabolism, and in more severe cases (like chronic shift-work) in diseases like diabetes, cardiovascular disease and obesity, and even mortality[1-6]. A stable clock is therefore a healthy clock.
When you wake up early during the week and late in the weekend, this is confusing for the biological clock, especially when there is a great difference between the times of waking up. For each day you go to bed and wake up at a different time, the biological clock has to adapt. When sleeping in during the weekend and waking up early on Monday again, the biological clock keeps adapting back and forth. In this way, the body does not fully get used to waking up early during the week. This could possibly be the explanation why you are feeling tired during the week.
What I personally notice, is when I am not used to waking up early, and I wake up early even though I get my hours of sleep, I am still tired. This is because the biological clock is not used to waking up at a different hour, and not because the body did not get enough sleep. When sleeping in during the weekend, the body is not well-adapted to waking up early during the week, and this can cause the sensation of fatigue.
Thus, when you are tired after waking up early for a week, the likely cause of this is that your rhythm during the weekend is different, and not because you don’t get enough sleep. The latter is of course still a possibility, and in that case you could try to go to bed earlier to see if that helps. The answer to the question: ‘Is sleeping in during the weekend beneficial?’ is therefore: No, the benefits of some extra sleep do not outweigh the disadvantage of a disturbed biological clock. If you still want some extra sleep during the weekend, the best thing to do is to go to bed earlier.
Of course this is not a very attractive message. When it is Friday, we want to enjoy our weekend by staying up late and do fun things. This message discourages that. You might accept and implement this message by enjoying your weekend in the morning instead of late in the evening, but I can imagine that you don’t want to give up your nights out. Alternatively, when you go out partying, it might be better to still wake up early (maybe one hour later than on a weekday). In this way, you will have some sleep deprivation, but you can solve this by taking a power nap during the day or by going to sleep earlier in the evening. The upside of this, is that your biological rhythm will be more stable, which will be more beneficial in the long run.
 Åkerstedt, T., Kecklund, G., & Johansson, S. E. (2004). Shift work and mortality. Chronobiology international, 21(6), 1055-1061.
 Ramin, C., Devore, E. E., Wang, W., Pierre-Paul, J., Wegrzyn, L. R., & Schernhammer, E. S. (2015). Night shift work at specific age ranges and chronic disease risk factors. Occup Environ Med, 72(2), 100-107.
 Antunes, L. C., Levandovski, R., Dantas, G., Caumo, W., & Hidalgo, M. P. (2010). Obesity and shift work: chronobiological aspects. Nutrition research reviews, 23(01), 155-168.
 Li, Y., Sato, Y., & Yamaguchi, N. (2011). Shift work and the risk of metabolic syndrome: a nested case-control study. International journal of occupational and environmental health, 17(2), 154-160.
 Trockel, M. T., Barnes, M. D., & Egget, D. L. (2000). Health-related variables and academic performance among first-year college students: implications for sleep and other behaviors. Journal of American college health, 49(3), 125-131.
 Wolfson, A. R., & Carskadon, M. A. (1998). Sleep schedules and daytime functioning in adolescents. Child development, 69(4), 875-887.
RESTAURANT REVIEW – MY ASIA
Our small but cosy town Wageningen is the decor of many cafés and restaurants. This is why the FoodCie decided to come up with something new! As friendly as real beasts are, we like to help each other by giving advice about where to eat and where NOT to eat.
Lets start this trip with some foodporn. A loooooong time ago, Ricky and I came up with the idea to go My Asia. I had never been to a Thai restaurant before and with an partial Asian boyfriend that is of course a no go. For some reason, probably too much time spended in the gym (oh no can’t be that, injurylife), it took us quite a long time to finally make the reservation. While some of you were probably hugging the toilet or waking up in a strangers bed, Kingsday was for us THE day!
Brave as we are, we decided to choose the four-course surprise menu. The appetizer consisted of several different small dishes, for example fried tempura shrimps, fishcakes and spring rolls. This time it was not save the best for last, but save the best for first! It was really delicious with a lot of different flavors.
As an in-between course they served us a turmeric soup with chicken, fried rice noodles and little sprinkles of swag (Ricky’s words). Again a great dish, although I have to say a bit heavy in flavor.
Then it was time for the main-course, which means in our case: MEAT. And with that I mean a lot of it… They depleted there pantry for us by serving crispy duck, red curry with beef slices and string beans, and a fried whole bream. All of it was cooked really well and tasted good. Ricky really enjoyed the food, which brought up some memories. Small side note: for me the coriander and mint were a bit overpowering.
We already have had the best part, right? Yes, but dessert is a good runner up. Here our ways parted and we ordered different dishes. I eat pancakes every day, so no surprise that the Thai pancake filled with icecream and whipped cream was going into my belly. A good and refreshing end of the evening. Oh, and the pancake was green, how cool is that?! Ricky was more adventures and chose the fried icecream. The ice inside was already melted, that was a small letdown, but the taste was there.
We really enjoyed the food, this restaurant is highly recommended and we are definitely going back!
We would rate the food with the number 8, service gets a 9 and the total ambiance gets a 7,5.
Ricky & Jasmijn
By Fleur van Griensven
You might have heard the saying: ‘Carbs are bad for you’ or ‘eating after 8 pm makes you fat’. A lot of people claim that this will result in fat gain. Are carbs really the enemy or are these two examples just one of the thousand misconceptions in the fitness industry? Can we actually benefit from cycling our carb intake whilst cutting? Is carb cycling the secret to get shredded?
What is Carb cycling?
Carb cycling is just what the name implies: Cycling the carbohydrate intake during the week, which translates into higher carb days and days with fewer/no carbohydrates. This is also called a non-linear dieting approach. A linear dieting approach means that the amount of calories and ratio of carbs/protein/fats remains the same every day. Thus, the non-linear dieting approach includes differences in the amount of calories, carbs, protein and fats between different days. I will try to make this clearer with an example.
If you would eat 200 g carbs, 150 g protein and 60 g fat 7 days a week you’d be following a linear dieting approach
If you would eat 250 g carbs, 150 g protein and 60 g fat on your 5 training days and 150 g carbs, 150 g protein and 60 g fat on your 2 rest days, you would be following a non-linear/carb-cycling diet.
With a carb-cycling diet, you basically manipulate your carbohydrate intake on different days of the week. Figuring out how much carbs to eat on these days is not that simple, but we will get back to that later on. In addition, I will give some tips on how to incorporate carb cycling in a diet yourself.
When can it be used and what are the benefits?
Carb cycling can be used both during a cutting (caloric deficit) and bulking period (caloric surplus). In this article, we will not cover carb cycling during a bulk. Carb cycling can be used from the start of a cut or when you go deeper into a caloric deficit. Most people will choose the second option. They do this because as calories are decreased a lot, it’s harder to stay motivated. Having different amounts of calories on different days might give you something to look forward to.
Carb cycling may have some potential benefits. Firstly, for some it gives a psychological boost and motivation to keep going. Implementing higher carb days gives you something to look forward to when dieting gets tough. The prospect of a day filled with pasta, bread or whatever carb source you’re craving can just be enough to keep on track with dieting.
Menno Henselmans, the founder of Bayesian Bodybuilding, has been talking about carb cycling in one of his interviews. Bayesian Bodybuilding uses an evidence and scientific-based approach to bodybuilding, so everything is based on scientific data. In this interview, Menno Henselmans says that there are almost no studies done on the carb cycling approach and the physiological benefits. The science about carb cycling is lacking, which I also encountered when digging deeper into this topic. Menno Henselmans believes that the few days during which the carb intake is increased, or higher carb days in general, do not have any practical physiological effect. A few days of increased carb consumption after several days lower in carbs is not enough to bring hormones related to hunger and appetite back to normal. 
There are however some studies that looked at the effect of an increased carbs intake for one or more days on a hormone that are related to hunger and appetite.
One of these hormones is leptin. Leptin is a hormone secreted (produced) by fat cells and controls both long-term energy balance and appetite. When body fat is going down during a cut, leptin production is decreased over time. This results in more and more hunger when you are deeper into a cut. Here the fun part of shoving your face with carbs comes in. Higher carb days, also called refeed days, are thought to bring the lowered leptin concentration back to a normal level. This will reduce the increased sensation of hunger (for a while), which might help you to stick to your diet.
However, recent studies did not show that a refeed or just one-high carb day can bring leptin levels back up. Yes, refeeding does give a rise in serum leptin levels, but leptin levels return to baseline (the starting point) after 24h. This means that leptin levels are not restored long-term. Switching between higher and lower carbs days is not going to do much for an improvement in leptin and thus those hunger feelings will still be there. 
Carbs are the main energy source during physical activity, because they provide the glucose that is required for energy. What most people experience is that eating more carbs will result in more energy during their training session. This results in them being able to train harder and lift more. That’s why it is recommended to have higher carbs on the heaviest training days.
How to set up your carb cycling plan? 
The most crucial thing in setting up macros for a carb cycling diet is to still have the same weekly total carb intake as you would have in a linear dieting approach. We leave aside protein and fat for the moment as they remain the same and we are only going to manipulate our carb intake on different days. Let’s go back to the example used earlier to show how you can set it up yourself.
On a linear diet, we would have 200 g carbs x 7 days = 1400 g of carbs per week.
For example, on a carb cycling diet it could look like this:
- 190 g 6 days per week and 260 g 1 day per week.
- 184 g 5 days per week and 240 g 2 days per week.
- 185 g 4 days per week and 220 g 3 days per week.
How you choose to set up your carb cycling plan is all personal preference. A few factors you can take into account are:
- How often do you train? If you only train two or three days a week, bigger carb load days might be more beneficial for you. If you instead train five or even six days a week, a more moderate spreading of carbs might be better.
- What are your heaviest training days? If adding more calories on these days gives performance a huge boost, go ahead and train the house down.
- What suits my lifestyle? Can you be a bit strict during the week and have more carbs to spend for burgers with friends during the weekend? Or would you rather have a more moderate carb intake?
Conclusion, Carb cycling: The secret to get shredded?
NO carb cycling is not the secret to get shredded. The secret to get lean is maintaining a caloric deficit for as long as needed to achieve the physique or shape you’re after. If cycling your carb intake (in whatever way you choose to do so) makes it easier to stick to your diet, carb cycling might be a good strategy. Alternatively, if you enjoy doing it and get results from it, then do it. However, keep in mind that it won’t give you better results than a linear-dieting approach with a daily constant caloric deficit. Whether you use a linear or non-linear dieting approach like for example carb cycling does not matter as long as your weekly caloric averages come out the same.
Take home message: Don’t overcomplicate the whole fat loss thing, it’s not rocket science. Stick to a caloric deficit, choose a strategy you can do consistent and rock the beach this summer!
 Henselmans, M. (Bayesian Bodybuilding). (2015, 24 February). Refeeds, Body Recomposition &
Non-Linear Diets. [Radio Podcast]. In Danny Lennon. Sigma Nutrition& Performance.
 Kolaczynski J, (1996). Responses of leptin to short-term fasting and refeeding in humans: a link with ketogenesis but not ketones themselves. Diabetes. 45(11):1511-5.
 Cheadle, N (2015, 13 November). Carb cycling for fat loss. Retrieved from https://www.nickcheadlefitness.com/carb-cycling-for-fat-loss/ on April 26th 2017
By Wietse In het Panhuis
Superfoods are a hot topic. Several people claim superfoods have high amounts of good nutrients and antioxidants, and numerous of beneficial health effects. When you eat a lot of superfoods, you will be healthy. Or will you?
What are superfoods?
Some well-known examples of superfoods are: Goji berries, cacao beans, chia seed, hemp seed, and coconut oil. According to the definition of the term superfood, a superfood is any food with a beneficial health effect. This term is actually a marketing term instead of a scientific term. There are no nutritionists, dieticians or doctors with an academic background that would promote the use of it.
Are superfoods super healthy?
Superfoods are claimed to have high levels of healthy nutrients and antioxidants, which in turn would have many health effects. Such effects include: Increases in energy and concentration, improvement of the immune system, even the prevention and curing of diseases (including cancer), anti-aging properties, and last but not least: Increases in life force! Is there any truth in any of these claims?
There is a flaw in the reasoning of articles that claim these things. You probably have seen it more than once: ‘Top 10 reasons to eat –insert superfood-‘. The superfood fights cancer, improves your eyesight, protects from cardiovascular disease, and so on. Here is an example to illustrate the reasoning behind most superfood articles is this: Superfood X contains vitamin A. A shortage of vitamin A has been shown to be bad for your eyes. Thus, when ingesting enough vitamin A by eating plenty of superfood X, these eye problems due to a shortage are prevented (true). Writers of these articles interpret this as: Eating enough vitamin A can prevent eye problems caused by a vitamin A shortage, therefore, Vitamin A is good for your eyes. Since vitamin A is good for the eyes, consuming more vitamin A is even better: You will improve your eyesight (false). Thus, superfood X improves the eyesight. In reality, vitamins (and other compounds) don’t work like that. They have a beneficial effect up to a certain point, and if you ingest more than that, it will not be more beneficial (and possibly even harmful). In superfood articles, the above described reasoning and exaggeration is often used. Hereby, the truth of a very small effect is turned into a miracle, a magic formula: When you eat this food, you will be healthy.
Superfoods are often claimed to have big effect sizes (in other words: a big impact on the body). These claimed effect sizes of superfoods are comparable to those of medicine (drugs), since medicine also has a big effect size on the body. Take anti-diabetic drugs for example: They improve glucose tolerance (an important measure in diabetes) and thereby give a significant ‘improvement’ of the situation. (This doesn’t mean that this is a good solution. It is treating symptoms, not treating the source of the problem.) In reality, single foods in general have a relatively small effect on health. There is not a single food (and thus not a single superfood) that could improve glucose tolerance like anti-diabetic drugs can, and this example goes for all drugs. However, when looking at a whole diet-lifestyle approach, big effects could be reached. It has for instance been shown that a good diet and exercise works just as well as medicine for treating diabetes. (This does not hold true for any disease. Cancer and many other diseases cannot be cured by nutrition, while chance of survival can be improved nonetheless.) So, diet and nutrition should be looked at as a whole, and not at the effects of single foods.
It is for the reason that single foods only have small health effects, that scientific studies on superfoods either find no truth in claims on single superfoods, or they conclude there is not enough evidence to support these claims. So far, there has not been a single (super)food that has miraculous health effects.
Some people swear by superfoods. They say eating a lot of superfoods everyday changed their life. They felt much healthier and energetic. In such cases, these persons often dropped their unhealthy habits, such as overeating and eating unhealthy products, and replaced these with superfoods. Undoubtedly, this is good for your health. However, when you would replace unhealthy foods with vegetables and fruits you would see the same effect. Superfoods are healthy foods in general, but they are not healthier than fruits and vegetables.
One problem that might occur when people depend on superfoods, is that they choose superfoods over vegetables because they think superfoods are healthier. This might result in a diet with little variation, while the key to a healthy diet is a varied diet. Variation in a diet assures that you get all the nutrients you need, since different foods contain different nutrients. In this way, superfoods might work counterproductive.
How expensive are superfoods?
Prices differ for different superfoods, but superfoods are generally sold in small packages with about 2 weeks worth of a daily serving. As an example, dried Goji berries from Body&Fitshop cost €4,90 for 250 grams. It is recommended to take at least 20 grams of berries per day, so a package lasts for about 12 days. Monthly this will cost you €12,15. When you look at table 1, you can see that a consumption of 20 grams of goji berries does not contribute a lot to the recommended daily intake (RDI), because this portion is small. Thus, goji berries are relatively quite expensive. Additionally, when you would eat greater amounts, this would contribute more to the RDI, but also would result in a high sugar intake.
This is only one of many examples, but in general you pay a lot for little product.
Table 1: Nutritional values of dried goji berries.
|Nutrient||Amount per 100 grams||Amount per 20 grams||% of ADH|
|Vitamin C (mg)||48||9.6||12.8%|
How are superfoods marketed?
People are often ranting on the pharmaceutical industry, since this industry has the primary purpose of making money, while not caring about the consumer’s health. It is true that a lot of money is being made in this industry and making money is always the driving force behind important decisions. However, I seldom hear people about the superfood industry. They are selling regular healthy foods for high prices, while marketing them as super beneficial for health. What they are doing is like selling tomatoes for three time the original price, and people buy it because of smart marketing. In this respect, there is little difference between the pharmaceutical industry and the superfood industry. When you read about superfoods, there is often a story behind it, like: The famous Li Qing Yuen (born in 1678) ate lots of Goji berries that grow in old protected valleys in Mongolia and Tibet. Li Qing Yuen became 256 years of age. Articles on superfoods often start with such a romantic story and then just give you a top 10 of the superfood’s (claimed) effects. Sometimes these background stories are obviously nonsense, like this example, but sometimes there are more impressive, believable stories. I remember one story about a sheep herder, who had a lot of sheep suffering from cancer. Then the sheep accidentally ate from a certain superfood, and the cancer disappeared. Of course, when common sense is used, you might find this story quite unlikely. There are however a lot of people without a background in biology and these topics. To those people, this can be a trustworthy story. Nearly all superfoods have been given a story like this, which is all part of the marketing trick.
One example of marketing superfoods is kale. As a Dutchman, you all know kale (boerenkool). Apparently, kale has been marketed as a superfood in the US. It has been called an antioxidant superstar with impressive anti-cancer effects. It’s good for this, good for that, etcetera, etcetera… Meanwhile, in the Netherlands we have been eating kale for a very long time. Is it healthy? Sure! Is it super? No. Is it expensive in the Netherlands? No. Is it expensive as a superfood? Take a guess. One funny superfood product called ‘Essential 10 Super Greens Super Food with Kale & Barley Grass’ contains kale and some other regular vegetables. This product costs €14,25 for 21 servings. That will cost you €20,- per month. One serving provides you with 20 to 35% of the RDI of fibres, vitamin C, vitamin K and calcium. This product thus contributes only a small part of the RDI of only four nutrients (there are over 20 vitamins and minerals). That means you still need to eat a lot of other foods to get everything you need. In comparison, when eating 100 grams of broccoli, this will contribute to 100% of the RDI of vitamin C, about 50% of the RDI of vitamin A, 22% of the RDI of copper, about 15% of the RDI of zinc, 14% of the RDI of fosfor, 11% of the RDI of iron, and 10% of the RDI of fibres. Broccoli is roughly said a better source of nutrients when taking portion sizes into account. 100 grams of broccoli costs €0,30 while one serving of the superfood costs €0,68. Thus, even though the above mentioned superfood might be good because of its fibre and vitamin K content (two nutrients that are more difficult to consume plenty of), it is way too expensive in relation to the small contribution to your health. (Of course it is difficult to make a 1 on 1 comparison, since you are not and you should not be eating broccoli every day, but you get the picture.)
People want to believe there are such things at superfoods, because we want to believe that we can dramatically improve our health by simply eating a few new products. The superfood industry exploits this desire by knowingly telling fairytales (such as the sheep story), and the next thing that happens is that some self-proclaimed food expert writes a book about super foods. After that, people start to blog about superfoods and how it changed their lives, and then share it on the internet. Anyone can write anything they want, while it is not checked whether the facts are true. Subsequently, other people will believe the claimed facts because they are uninformed, and have a strong desire to do what is best for their body. More and more people will start buying foods and spreading the word on the amazing effects of superfoods. This is a vicious circle that keeps expanding. It is brilliant marketing from the superfood industry.
Conclusion – superfoods: yay or nay?
Concluding so far:
- The term superfood is a term invented as a clever marketing strategy
- Superfoods are healthy, but they are not healthier than regular foods
- Superfoods are expensive
Superfoods: yay or nay? NAY!
In general, superfoods are a waste of money if you buy them because you think they are super healthy. Are superfoods bad for you? No, they are healthy products, but you still need variation in your diet. If you like your money, you are better of buying regular fruits and vegetables, because they are equally healthy and much cheaper. Buying regular fruits and vegetables will save you a lot of money. Of course, when you buy superfoods for their taste, that is totally up to you.
If you love eating superfoods and are feeling great by doing it, please feel free to do so. The message of this article is: Just don’t get deceived by this marketing strategy. There are no magical formulas for being healthy.
 Gillies, C. L., Abrams, K. R., Lambert, P. C., Cooper, N. J., Sutton, A. J., Hsu, R. T., & Khunti, K. (2007). Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis. Bmj, 334(7588), 299.
 Bessen goji- gedroogd (NEVO-code 3445), NEVO-online versie 2016/5.0, accessed on 31-03-2017. http://nevo-online.rivm.nl
Amount: Food: What:
500g Lean beef steak Cut
2 Onions Chopped
3 cloves Garlic Chopped
3 dL Water
3 tbs Sweet soya sauce (Ketjap Manis)
4 Potatoes Pealed
1 tbs Laos Pealed and chopped
Bit of Palm sugar (Gula Djawa)
2 Bay leaf
2 ts Nutmeg
…. Salt & peper
- Make the Bumbu by pealing and chopping the garlic, onion and laos. Now add the Bay leafs and Clove(s).
- Peal the potatoes and cut them into slices.
- Take a hot Wok with some oil and fry the sliced potatoes.
- Slice the meat into cubes and with the margarine bake them until they are light brown.
- Add the Bumbu.
- Bring it to the boil and add the Sweet soya.
- Wash the tomatoes, chop them and add.
- Lower the fire to its lowest and let it sit for approximately 2 hours until the meat is cooked and the sauce is thickened.
- Add the fried potatoes and stir gently.
- Lastly remove the Bay leafs and Clove(s).
Take some nice cooked rice and enjoy this lovely traditional Jakarta dish!
|Whole dish (without rice)||Per person|
By Wietse In het Panhuis
A common myth is that you should not use extra virgin (olive) oil for baking. This myth states that this might be bad for you due to trans-fat formation, and that the taste will adversely change. Is there a healthier alternative? Is this myth true or not? Keep on reading to find out!
What are trans fats?
Trans fats are unsaturated fatty acids, of which the geometric configuration (the way the atoms are ordered in the fat) is different from (cis-)unsaturated fatty acids that we are familiar with. As can be seen in the picture below, both fatty acids have exactly the same atoms in the same order. The only difference is the placement of the hydrogen atoms (H) at the double bond (indicated with the red and blue circle). At the cis-bond, the hydrogen atoms are at the same side of the carbon chain, and at the trans-bond, the hydrogen atoms are at the opposite side. This small structural difference could cause big differences in important factors such as the melting point, and can thereby explain differences in healthiness between trans fats and non-trans fats. Processes such as heating can change the configuration of a bond from cis to trans. In other words: heating of unsaturated fats can result in trans fat formation. This is only possible if fats contain a double bond. Since saturated fats do not have a double bond, trans fat formation can only occur in unsaturated fats.
Regulation of trans fats
Since the 1950s, trans fats have been abundantly used in the food industry. Trans fats do not only occur naturally in foods, but are also a byproduct formed by production processes such as hydrogenation of vegetable oils (a process during which liquid oils are converted to solid or semi-solid fats). The latter form is called artificial trans fat. It is generally known that artificial trans fats are bad for health. Consumption increases the risk of multiple cardiovascular risk factors and coronary heart disease events such as heart attack and stroke. It is for that reason that use of artificial trans fats was banned in 2006 by the FDA. Trans fats occurring naturally in animal products are also thought to be unhealthy, but they are probably not as worse as artificial trans fats (and trans fat levels are also much lower compared to food products containing artificial trans fats). Thus, it can be concluded that trans fats are unhealthy.
Oil baking/frying and trans fat formation
Trans fats are also formed by heating of vegetable oils, such as olive oil. Especially during deep-frying, a lot of trans fat formation will occur. However, this trans fat formation predominantly occurs at high temperatures (150-200+ degrees Celsius). Therefore, baking or stir-frying with vegetable oils hardly induces trans fat formation, even not at high temperatures as confirmed by this study. Thus, baking with oil in general will be safe with regard to trans fat formation.
Differences between extra virgin/refined
What is the exact difference between extra virgin olive oil and refined olive oil? Oil is produced by the extraction process of vegetables and seeds, such as olives, sunflowers, rapeseed, and so on. There are many different names for each oil. There is refined olive oil, virgin olive oil and extra virgin olive oil (and some other examples on which we will not go into detail). The difference between these oils is the degree of processing and thereby the quality of the oil. Extra-virgin olive oil is of the highest quality, followed by virgin olive oil and lastly refined olive oil. The word virgin indicates that the olives were pressed in order to extract the oil. This is the purest form of oil, and thus has the highest quality. This is different from refined oils, which have been produced by chemical or heating processes after the olives are pressed to create virgin oil. Thus, the big difference is the amount of nutrients and the sensory properties (or in other words, the taste).
Both refined and (extra) virgin olive oil are high in poly unsaturated fatty acids (PUFAs), which are healthy compared to saturated fats. Thus, cooking with oil is always better than cooking with butter(based) baking products, as these contain more saturated fats and less PUFAs. Additionally (extra) virgin olive oil contains a lot of polyphenols (e.g. vitamins E and K, phytosterols and polyphenols), which have been proven to have protective health effects with regard to cardiovascular diseases[4,5]. A lot of these compounds function as antioxidants. Thus, extra virgin olive oil is the best choice to consume, as this is the most healthy one.
What happens when extra virgin olive oil is heated?
It is often said that when extra virgin olive oil is heated during baking, the taste changes and trans fats are formed. This would not be the case for refined oils.
Firstly, like previously stated, heating oils at low temperatures (like temperatures during baking) cannot (or hardly) produce trans fats. The only difference between extra virgin oil and refined oil is quality and nutrients. It would therefore be weird that trans fats would be formed when baking with extra virgin, but not with refined olive oil. Thus, we can safely assume that no trans fats will be formed when baking with extra virgin (olive) oil.
Nonetheless, there are some changes occurring in the extra virgin olive oil during baking, otherwise the taste would not change. Some of the antioxidants in the oil are thought to be degraded during baking. I could not find studies looking exactly into this problem. Most studies are looking at changes in extra virgin olive oil due to deep frying. In addition, the total amount of polyphenols in the oil consists of a lot of different compounds, of which many we did not identify yet. It is therefore difficult to measure all the polyphenols, so answering the question how many polyphenols are degraded due to baking proves to be difficult. From my personal point of view, I don’t believe that all the polyphenols present in the oil will be degraded by baking shortly with oil, as these temperatures are relatively low and heating duration is short. Therefore, even though some of the polyphenols are lost, there are still more polyphenols remaining than when cooking with refined oil in which hardly any polyphenols are present. With this respect, extra virgin olive oil would still be a healthier choice to bake with. A study that investigated the effect of heating on antioxidants and polyphenols in virgin olive oil confirms this hypothesis. This study showed that the antioxidants present in the oil have a protective effect on polyphenols. In other words, heating degrades antioxidants while most of the polyphenols are spared and still intact.
However, it is true that heating extra virgin olive oil changes the taste of the extra virgin olive oil. You have to decide for yourself whether you think this is a problem or not. Extra virgin oils have a more distinctive taste than refined oils. This characteristic taste will change. I myself do not have a sophisticated taste. I therefore do not mind if the distinctive taste of extra virgin oil is changed during the baking. I do not taste much difference between baking with refined oil or extra virgin olive oil. I care more about the health properties. Think of it like this: If you are baking with refined oil, the taste is of less quality than extra virgin olive oil. When baking with extra virgin olive oil, the taste does not get worse than refined oil, so you might as well choose to bake with extra virgin oil since it’s healthier.
Concluding: not baking with extra virgin oils? Myth!
Let’s summarize what we have found:
- Baking with extra virgin oil does not produce trans fats.
- When baking with extra virgin oil some antioxidants (polyphenols) are lost, but most of the polyphenols will still be present in the oil.
- The taste of extra virgin oil may be affected by heating. You should decide for yourself whether you find this important.
Thus, when approaching this health-wise, the myth that you should not use extra virgin olive oil for baking is not true.
Disclaimer: In this article I only talk about baking and not about deep-frying. When you are deep-frying, olive oil is not a good choice as a lot of trans fats will be formed. In this case more stable oils such as sunflower oil are healthier alternatives.
 Mozaffarian, D., Aro, A., & Willett, W. C. (2009). Health effects of trans-fatty acids: experimental and observational evidence. European journal of clinical nutrition, 63, S5-S21.
 Przybylski, R., & Aladedunye, F. A. (2012). Formation of Trans fats: during food preparation. Canadian Journal of Dietetic Practice and Research, 73(2), 98-101.
 Schwab, U. (2014). 1, Lauritzen L 2, Tholstrup T 2, Haldorssoni T 3, Riserus U 4, Uusitupa M 5, Becker W 6. Effect of the amount and type of dietary fat on cardiometabolic risk factors and risk of developing type 2 diabetes, cardiovascular diseases, and cancer: a systematic review. Food Nutr Res.
 Morrison, M. C., Mulder, P., Stavro, P. M., Suárez, M., Arola-Arnal, A., Van Duyvenvoorde, W., … & Kleemann, R. (2015). Replacement of dietary saturated fat by PUFA-rich pumpkin seed oil attenuates non-alcoholic fatty liver disease and atherosclerosis development, with additional health effects of virgin over refined oil. PloS one, 10(9), e0139196.
 Khurana S, Venkataraman K, Hollingsworth A, Piche M, Tai TC. Polyphenols: benefits to the cardiovascular system in health and in aging. Nutrients. 2013; 5(10):3779–827. doi: 10.3390/nu5103779 PMID: 24077237
 Pellegrini, N., Visioli, F., Buratti, S., & Brighenti, F. (2001). Direct analysis of total antioxidant activity of olive oil and studies on the influence of heating. Journal of Agricultural and Food Chemistry, 49(5), 2532-2538.
A nice, comforting soup, perfect for these cold days. The lentils provide this soup with a nice amount of vegetable protein and some texture. The spices ensure an awesome flavor.
- 275 g red lentils
- 2 tbsp of olive oil
- 1 large onion, finely chopped
- 2 garlic cloves, peeled and finely chopped
- 1 tsp cumin
- 1 tsp coriander
- 2 tsp garam masala
- 1 tsp ginger
- ½ tsp turmeric
- 1 tbsp tomato puree
- 1-1.5 cubes of chicken stock
- 4 tbsp yoghurt
- Rinse the lentils until the water that you drain from them is clear.
- Prepare the stock by boiling 1 litre of water and adding the chicken stock cubes.
- Heat the olive oil in a pan and add the onion and garlic.
- Cook until golden, about 4-6 minutes.
- Add the tomato puree and cook for 2 minutes.
- Add the spices, fry shortly, and then add the lentils and stock.
- Bring the soup to a boil and leaver to simmer on low heat for 25-30 minutes. Stir a few times in between.
- Shortly blend the soup using an immersion blender or a blender. The goal is to have the soup remain somewhat chuncky.
- Ladle the soup into bowls and swirl some yoghurt on top.
|Whole dish||Per person|
By Wietse In het Panhuis
Do you have trouble falling asleep? Are you sleeping long, but are you still feeling tired? Do you have a disturbed sleep rhythm and do you want to change it? I addressed these questions and many others in my recent lecture on sleep and rest. For members there is an opportunity to watch the lecture online (it is posted in our Facebook group under videos) in case you missed the lecture. Nonetheless, I will summarize my lecture in this article. First, I will provide some background information on sleep and rest, and afterwards I will give some tips on how to change sleep rhythm and improve sleep.
The biological clock is a ‘system’ in the brain that regulates the daily rhythm of +/- 24 hours. As most of you might know, the biological clock plays an important role in the sleep rhythm. In humans (and many other animals), this rhythm is not exactly 24 hours. This system, also called the suprachiasmatic nucleus (SCN), which is located in the hypothalamus of the brain, is set like a stopwatch: every day it counts down 24.2 hours. This would mean that after one month of such a rhythm, your rhythm will have shifted 6 hours (30 times 0.2 hours per day). Luckily, this system (or stopwatch) is able to adapt in such a way that this clock becomes 24 hours exactly. This adaption (or entrainment) can happen because the body is able to register signals from the surrounding environment. These signals (or stimuli) tell us something about the time of the day, and are therefore also referred to as ‘zeitgebers’ (=time-givers). The most important zeitgeber is light. The SCN is able to register light, which will result in a signal of ‘day’. In the absence of light, the SCN will interpret this as ‘night’. This adaptation of the biological clock, also called the pathway of light entrainment, is displayed simplistically on the picture on the right (retrieved from: https://www.nigms.nih.gov/education/pages/factsheet_circadianrhythms.aspx). Here you see that light travels to the SCN through the eyes, which will result in a message of ‘day’ in the brain.
Most of you probably have also heard of melatonin. This hormone is released in the brain (in the pineal gland (hypofyse in Dutch)) during the evening, and levels peak during the middle of the night (and are low to zero during the day). Melatonin makes you feel tired and stimulates the body to fall asleep. Therefore, melatonin plays an important role in the sleep rhythm. Melatonin is also involved in the pathway of light entrainment (which was described above). During the day, the light will tell the SCN that it is ‘day’. The SCN in turn will inhibit or block the pineal gland, which will prevent the pineal gland from releasing melatonin. During the evening, the absence of light will allow this inhibition to stop: melatonin will be slowly released, and you will become tired.
The eyes are especially sensitive to blue light, which means that of all colors of the light spectrum, blue light has the greatest impact on the SCN. This means that blue light gives the strongest signal to the brain that it is day. Blue light is highly present in televisions, laptops, smartphones, etcetera. You might imagine, that when the eyes are exposed to a lot of blue light during the evening, this will inhibit melatonin to be released, and will result in problems falling asleep. So if you use these devices a lot during the evening, this can lead to sleeping problems.
Sleep and training
The main function of sleep Is cognitive recovery; to give the brain rest, and to store the memories that are made during the day. Of course the body also rests and recovers during sleep, but recovery from training also occurs during the day (when you are sitting or lying down). In addition, sleep duration does not seem to be associated to heavy exercise: top athletes do not need more sleep than non-athletes[5,6]. Thus, sleeping more is not essential in recovering from training. However: sleep deprivation can hamper recovery. Thus, make sure to get your hours of sleep, but you do not need more than that. This will probably raise the question: how many hours do we need?
How many hours of sleep do we need, and how is this determined?
Age is the most important determinant of how much sleep one needs. Newborns need most sleep, and elderly least. However, within the same age groups, there are large differences in how much one sleeps. How much sleep you (as an average adult) need is determined by mainly two factors: genetics and habit. It is not exactly known how important the genetic factor is, in other words: how great the difference in required hours of sleep is between persons solely due to genetic differences. However, it is known that habit can cause great differences and that the role of genetics in sleep duration is probably small. All in all, no clear conclusions can be drawn on how much sleep an individual actually needs. So… now you still don’t have an answer to the question: how much sleep do you need?
Even though differences in individual sleep requirements are not known yet, one study looked at the average hours of sleep and the corresponding mortality ratio in a group of over 1.000.000 people. The mortality ratio tells something about the relative chance of death, compared between groups (if you do not understand it: it can be interpreted as an indication of how healthy someone is). These mortality ratios can be seen in the figures below (retrieved from Youngstedth et al 2004).
The first thing that can be concluded from these graphs is that there are hardly any differences between women and men in the mortality ratios of each group with different sleep durations. The figure also shows that people who sleep between 6.5 and 7.5 hours per night have the lowest mortality ratio and can therefore be seen as most healthy. The figure also shows that the mortality ratio increases with less than 6.5 hours of sleep, but what’s striking, is that the mortality ratio increases even more if people sleep longer than 7.5 hours of sleep. Also, on average, sleeping more than 9.5 hours a night is worse than sleeping 2.5-3.5 hours a night. Of course this is only one study, but it gives a good indication for the general population (side note: the study did adjust for lifestyle, physical activity and dietary factors).
Now there are some people who sleep 9 or even more hours a night, and if they sleep less, they are tired and not functioning. As you read before, genetics play a small role in differences in sleep duration, so this is a good example of habit. The body gets used to the amount of hours you sleep (Small intermezzo to illustrate this. Polyphasic sleep regimens are sleeping patterns during which you sleep (the most extreme example) only 2 hours per 24 hours. Every 4 hours you sleep 20 minutes. Within these 2 hours you rest as much as during a normal 8-hour night, since this sleep solely consists of deep sleep which has a higher restorative capacity. Anyone can get used to such a sleep pattern, but it takes a very long time to get used to. These polyphasic sleep regimens are a perfect example that shows that sleep is mainly determined by habit). If one would sleep 6 hours every night for many(!) nights in a row, the body will adjust the restorative capacity of sleep: one would have more restful sleep (more deep sleep, as deep sleep is most important in recovery). If one would sleep 9 or 10 hours for many nights in a row, the sleep rhythm will adjust to that: one would have relatively more light sleep (light sleep is not very important in recovery). In conclusion, even though there might be some genetic differences in how much sleep one needs, habit probably explains the large differences in sleep duration between people. Therefore, one can also change their habits and thus change their total sleep duration, which will result in more (productive) hours during the day.
How to change the sleep rhythm?
Now, how can one change his sleep rhythm? You might want to change your rhythm in case you go to bed late and wake up late, and you want to advance these times, or when you want to reduce your sleep duration in case you are sleeping 9-10 hours a night, as mentioned in the last paragraph. To help you with this, I have some tips:
- Be consistent! The biological clock is a complex mechanism, which is why it adapts very slowly to changes in your daily rhythm. Thus, be consistent in the time you go to bed and when you wake up. Sleeping late during the weekend with the intention to catch up sleep actually disturbs your rhythm, as this is a sudden, large change for your rhythm. Also, when you want to change (advance) your sleep rhythm, try to go to bed and wake up 5-15 minutes earlier every single day.
- When step 1 does not really work for you, since you are having problems with falling asleep earlier than usual, you might cold turkey your rhythm. Just set your alarm clock 1-2 hours earlier than you are used to and stick to it: wake up every day at this time. Your biological clock will have a harder time to adapt and will be disturbed due to the large change, but your body and brain will be more tired during the evening, which will aid in falling asleep. Doing this is more exhausting than option 1, as you will experience tiredness until your biological clock has adapted. Adapting completely might even take a few weeks! One important side note: when doing this, you will probably be more prone to fall asleep during the day. However, it is important you do not take daytime naps, as this will hinder sleep onset at night!
- A third option that might help is melatonin. As mentioned before, melatonin is a hormone that is produced by the pineal gland in the brain and is released (secreted) during the evening. Melatonin causes the typical feeling of being tired when it is getting darker outside. This hormone is also available in supplement-form. Taking low dosages of melatonin supplements a few hours before going to sleep can stimulate and advance the melatonin production of the body. This helps you fall asleep earlier and thus advance your sleeping rhythm. One important side note: do not use this chronically, and do not use high dosages. Chronic use or high dosages of melatonin can hamper the melatonin production of the body, and will result in melatonin-resistance: your body needs more melatonin to experience the same effects (due to receptor insensitivity, which basically happens when you administer any kind of drug).
How to improve sleep?
If you want to improve sleep (e.g. when you have trouble falling asleep or in case you are experiencing restless sleep such as frequent awakenings during the night) I also have some tips for you. Do mind, that not all of these tips are practical or feasible, but from a theoretical point of view to optimize sleep.
- Increasing zeitgeber strength can make the biological rhythm stronger and the sleep cycle better. This means, that when differences between day and night are greater, the body will have a stronger perception of day and night (zeitgebers). This can be done by:
- Decreasing the amount of light during the evening (dim the lights of the lamps and the television).
- Downloading a blue light filter on laptops and smartphones. As mentioned before, blue light exposure during the evening can inhibit melatonin release. This application filters most of the blue light from the screen, which will diminish inhibition of melatonin release.
- Limiting light from entering the room during the night, by having good curtains, and switching off all the lights.
- Spending the day in the light. Sunlight exposure can help, but also switching on lights inside the house when it is cloudy outside, will keep the light signals (zeitgeber strength) high.
- Avoid drugs (or psychostimulants). Pretty obvious, but that doesn’t make it less important. Avoiding substances such as hard drugs (MDMA, speed, etc.), but also limitation or elimination of smoking (nicotine), caffeine[14,15] and alcohol will help in order to optimize the nights rest. Consumption of these substances are all related to a decrease in sleep quality. A little side note for caffeine: there are large differences between persons in their sensitivity to caffeine (due to genetics and habit). This explains why some people can drink coffee during the evening without having difficulties falling asleep, while others have these difficulties when they drink coffee at 3 pm. Therefore, there are no clear conclusions about this yet, but as a general rule of thumb it is wise to avoid caffeine consumption (coffee, energy drinks) 6 hours prior to bedtime, and limit consumption of tea and soft drinks throughout the day[14,15].
- Limit stress. Stress can have a great impact on sleep: falling asleep is more difficult, sleep quality is less, and it will cause feelings of fatigue during the day. Limiting stress is therefore essential for optimizing sleep. However, this is easier said than done. Terminating stress from daily life can be achieved by looking at the stressor: what causes the stress? Are you able to eliminate this from your life? If it is not possible to change this stressor, it is better to change your attitude and how you perceive this stressor. Now this is quite an extensive topic, which is why we will discuss it more thoroughly in another article. For now, I can recommend meditation or yoga. A lot of people are not into this, but before dismissing it, you could give it a try. It takes some practice, but then it can be really beneficial and enjoyable. If you don’t want to try this, you might try a quick, easy tip: 4-7-8 breathing. This can be done when lying in bed when attempting to fall asleep. It is a special way of breathing that allows your mind and body to fully relax. With this technique you breathe in for 4 seconds, hold this for 7 seconds, and breathe out for 8 seconds. Do this very slowly, breathe deep into your belly and not your ribcage, and try to relax all your (facial) muscles. Doing this lowers the heart rate, relaxes the muscles, and lets the mind focus on the body instead of thoughts and will thereby help you to fall asleep more easily (this actually is the basic principle of meditation). You can look up 4-7-8 breathing on YouTube or Google for a more detailed explanation.
- My last and most important tip, is to think positively. The mind and body are closely connected. People who suffer from depression are feeling physically sick and people who are happy are physically healthier than when they wouldn’t be happy. Besides this, the mind also plays a crucial role in sleep. When you think you had a good night of sleep, you will feel energetic. When you think you had a bad night of sleep, you will feel tired. Your perception of sleep influences how tired or energetic you are. A good illustration of this, is a study that looked at elderly insomniacs: elderly people who suffer from chronic sleeping problems. From all possible non-pharmacological interventions that improve sleep, Cognitive Behavioral Treatment (CBT) seemed most effective in improving sleep in these insomniacs[18,19,20]. This treatment is normally applied for patients suffering from depression, as it helps to change unhelpful thinking and behavior. Thus, CBT, which helps in thinking more positively, seems to be most effective in improving sleep and energy levels during the day. This example shows how important mindset is in sleep. My message to you: don’t worry if you have one bad night of sleep. You will be fine! Your body is well able to deal with a little less sleep every now and then. Don’t let this influence how you feel! The same goes for those people who sleep 9-10 hours a night: you don’t need this, 8 hours will be fine. It is just a matter of mindset and habituation.
I hope these tips will help you, they sure have helped me improve my sleep. Good night all!
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