Tag Archives: health

The best exercise for your health

Have you ever wondered which exercise would be best to keep you healthy as you get older? I guess the answer is “the one you like”, but Pedro Angel Latorre-Roman and his colleagues wanted to investigate this further and compared master long distance runners with athletes engaged in gym work and sedentary people.15308809285_249e075362

 

 

 

 

 

47 long distance runners and 49 bodybuilders from local clubs volunteered for the study, and were compared to 47 sedentary people. All the participants were male, and between 35 and 60 years old. They were divided in groups according to their age (35-40 year, 40-50 year and 50-60 year old).

The researchers calculated their BMI, measured their body fat percentage, and analysed their quality of life using a questionnaire. The participants performed countermovement jumps and had their hand grip measured to test their strength.

Unsurprisingly, the long distance runners as well as the bodybuilders maintained their strength much better throughout aging than the sedentary people, even though muscle mass was decreased in all the older participants compared to the younger ones. The runners showed healthier BMI values and body fat percentages, and scored better in the quality of life questionnaire than both other groups. However, they lost more muscle mass than the bodybuilders as they grew older.

This study confirms a previous study by Williams, which showed that running is much more effective in keeping your body fat percentage healthy than other sports. Williams compared the BMI and waist circumference of 33,374 runners with the kind and amount of exercise they were doing. Most runners do not only run, but are also engaged in a wide variety of different sports, such as cycling, walking, swimming… He noticed that those who ran more were leaner, even if the total amount of energy spent exercising was the same.

Both studies are off course observational, which means that they can only show an association between two findings. It does not mean that one leads to the other, as there might be a third factor which explains the association. For example, there is an association between lying in bed and dying, as most people die in bed, but this is explained by disease and injury.

It is also possible that lean people are more often tempted to take up running than other people.

The same could be true concerning the results of the quality of life questionnaire: are you happy because you are running, are you running because you are happy or is there another explanation?

References:

PA Latorre-Roman, JM Izquierdo-Sanchez, J Salas-Sanchez and F Garcia-Pinillos. Comparative Analysis between two models of active aging and its influence on body composition, strength and quality of life: long-distance runners versus bodybuilders practioners. Nutr Hosp. 2015; 31(4): 17-25.

PT Williams.  Non-exchangeability of running vs. other exercise in their association with adiposity, and its implications for public health recommendations. PLoSOne. 2012; 7(7): e36360. doi:10.1371/journal.pone0036360.Epub 2012 Jul 13.

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Keep your teeth healthy to reduce your injury risk

5128567045_fca804fea6A study by Henny Solleveld on soccer players suggests that poor oral health increases the risk of sports injuries and muscle cramps. As soccer players run a lot during a match, these results are probably important for runners as well.

Sports injuries are common, not only between runners but also between soccer players.  The risk factors can be intrinsic or extrinsic in nature. The extrinsic factors include interactions between players, and the intrinsic ones comprise health, previous injury, age, fitness, stress, anxiety…In this study, Henny Solleveld and her colleagues show that oral health should also be included in the intrinsic factors.

They questioned 184 premier league and 31 elite junior soccer players about re-injuries, muscular cramps, oral health, age, player position and psychosocial factors (stress and anxiety).

They noticed that poor oral health was associated with cramps and all kinds of injuries, even if they controlled for age, player position, diet or stress and anxiety.

Of course, it is not because there is an association between two factors that one leads to the other. There might be a third factor that leads independently to poor oral health and injuries, or it might just be a coincidence.

However, it is possible, as theoretically there is a mechanism. Poor oral health leads to an increased amount of inflammatory factors in your blood which make your muscles more easily fatigued and increase oxidative stress. Muscular fatigue puts you at a higher risk of injury as you lose good technique and as your coordination deteriorates. It can also lead to cramps.

This study is based on questionnaires and, as we all know, participants can get the answers wrong. Moreover, it is only a small study. It would therefore be good to see it repeated on larger groups. In the meanwhile, it is good idea to see your dentist regularly!

Reference:

H Solleveld, A Goedhart and L Vanden Bossche. Associations between poor oral health and reinjuries in male elite soccer players: a cross-sectional self-report study. BMC Sports Science, Medicine and Rehabilitation 2015; 7:11. doi:10.1186/s13102-015-0004-y.

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Exercise and mortality

5797534694_a36e9d8b0dExercising helps you to live longer, whatever the amount you are doing. If you exercise a little, your risk of an early death drops and if you exercise a lot, it drops even more. This is the conclusion of a study published on April 6th in the JAMA.

If you plot “benefits” against “dose” on a graph, most biological systems will show an inverted “U”. Take food for example: if you eat too little, you might die, but if you eat too much, you might also die. If you take a medicine, you have to take the right amount, as taking not enough will have no effect and taking too much is toxic.

Is the same true for exercise? Everybody agrees that you need a minimum of exercise to stay healthy, but some people believe that too much is bad for you. The recent cases of sudden deaths during competitions and the findings of heart rhythm disturbances in older endurance athletes have fuelled the debate.

To answer this question, Hannah Arem and her colleagues have looked at the mortality rates and physical activity levels of 661 137 men and women over 14.2 years.

Sure enough, they showed that having the recommended amount of exercise (a minimum of 150 min of moderate intensity, or 75 min of vigorous intensity endurance exercise per week) resulted in a 30% lower mortality risk compared to not exercising at all. However, any exercise is much better than none, as people who did less than the recommended amount already reduced their mortality risk by about 20%.

Working out more is even better, and exercising 2 to 3 times the recommended amount reduces your risk by 37%, while doing 3 to 5 times more leads to a 39% reduction.

The researchers noticed that those who exercise 10 times or more the recommended amount did not reduce their risk any further, but they could not observe any evidence of harm either.

Can I believe this?

This is very large study, which makes it trustworthy. Moreover, the results are the same for both genders and all BMI ranges.

On the other hand, it is based on questionnaires, and participants can easily over- or underestimate what they are doing or change their habits. However, most population studies about exercise and mortality suffer from these same limitations.

If Hannah Arem is right, concerning exercise, there cannot be too much of a good thing. Even though I have never met anybody running marathons or participating in triathlons for health reasons only, it is good to know we are not harming our bodies.

Keep going, but make sure that you avoid overtraining and injuries!

References

Arem H, Moore SC, Patel A et al. Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship. JAMA Intern Med 2015; DOI:10.1001/jamainternmed.2015.0533. (Abstract)

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Do you need to exercise if you are healthy?

14022436150_97d48f6579Exercise improves your health, even if you are fit.

What is the importance of exercise if you are young, fit and healthy? Researchers in Finland have tried to answer this question by studying male identical twins. As these brothers are identical at the gene sequence level, any difference should be due to lifestyle factors.

They recruited 10 healthy male identical twins between 32 and 36 years old, of which only one brother had been exercising regularly for the last three years. They then measured their body weight and fat percentages, assessed their glucose levels and insulin sensitivity, and calculated the volume of their brains’ grey matter using magnetic resonance imaging.

The active twins had a higher VO2max and less visceral fat than their sedentary brothers, even though their body weight was not that different. Their glucose levels were lower and their insulin sensitivity* was higher. They also had a higher volume of grey matter in those areas associated with motor control.

The researchers concluded that even among healthy young adults exercise makes a difference. This is important, as lower fitness levels, more visceral fat and poor glucose metabolism are associated with chronic diseases later in life. Obviously, the negative effects of being sedentary begin early!

You might wonder if you have taken up exercise because you have a more favourable genetic profile than sedentary people. If so, you would be healthier whatever you do. This study suggests that this is not the case and that exercise makes a real difference, since identical twins should have the same genetic profile. This does not mean that genes do not matter. They are very important indeed, but you can influence them by your lifestyle.

This is only a small study. It would be great to confirm it with larger ones, but it must be very difficult to find a large group of identical twins of the same sex and age group with different exercise habits.

* Insulin sensitivity = how sensitive the body is to insulin stimulation. Low sensitivity is associated with higher risk of diabetes type 2.

References:

Rottensteiner M, Leskinen T, Niskanen E et al. Physical acivity, fitness, glucose homeostasis, and brain morphology in twins. Med Sci Sports Exerc. 2015; 47(3): 509-518.

Picture:

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Keep running to walk better

A number of physiological parameters, such as VO2max and lactate threshold, describe your ability to run well. Most of them decline as you get older, except for running economy. Running economy is the energy you spend to run at a given speed, in other words: it corresponds to what it costs your metabolism to make the movements.medium_14682933349

Studies have shown that older runners are just as economical as younger ones. Walking economy on the other hand becomes worse in people who use to walk for exercise just as it does in sedentary people. A paper published in PloSOne by Justus Ortega now suggests that running will allow you to keep the cost of walking down.

This is much more important than you might think because keeping the ability to walk easily is essential if you want to live independently in your old age. Moreover, there is a correlation between losing this ability and getting ill, showing how important it is for your life expectancy.

To find out what you can do to keep the cost of walking down, Justus Ortega and his colleagues compared the cost of walking of 15 older walkers with that of 15 older runners. (You can read the article for free if you want to know how they did it exactly.) They showed that the older runners’ cost of walking was much better than the older walkers’ and, of course, than sedentary older people’s. It was just as good as that of young sedentary adults.

What influences running/walking economy?

Your muscles and tendons have to be able to store and release elastic energy, they have to fire at the right moment and work together effectively to support your body weight, do the work, maintain your balance and allow the leg swing.

Your economy is also determined by the ability of your muscles to produce energy, such as the number and efficiency of your mitochondria and their enzymes.

Why older runners keep their walking cost low is not clear, but Justus Ortega and his colleagues suggest that the intensity of exercise is crucial. They think you might have to exercise harder, longer or more frequently if you want to keep your cost down. This would confirm a previous study, where elderly women performing high intensity walking workouts improved their economy by about 20%.  On the other hand, a year-long fitness program including strength and balance exercises did not have any effect.

Can I believe this?

This is an observational study, and just like any other observational study it does not prove cause and effect. In other words: the runners might have a better walking economy for reasons not related to running at all. Maybe they have become runners instead of walkers because their exercise economy was better due to a more favourable genetic profile.

Furthermore, this is a small study, and the results might simply be due to chance –or bad luck- while in de general population there is no difference.

It is clear that we need further studies, but in the meanwhile it is a good idea to have a healthy balance between high and low intensity exercise.

Disclaimer: this article is for general information only, and does not replace medical advice. It cannot be used to diagnose or guide treatment. If you have any concerns or questions, you should talk to a qualified health provider

References:

Elbaz A, Sabia S, Brunner E et al. Association of walking speed in late midlife with mortality: results from the Whitehall II cohort study. Age (Dordr) 2013; 35(3): 943-52.

Ortega J, Beck O and Roby J. Running for exercise mitigates age-related deterioration of walking economy. PloSOne 2014; doi: 10.1371/journal.pone. 0113471. (accessed: 28/12/2014).

Milan OS, Thom JM, Ardigo LP et al. Effect of a 12-month physical conditioning programme on the metabolic cost of walking in healthy older adults. Eur J Appl. Physiol. 2007; 100: 499-505.

Saunders PU, Pyne DB, Telford RD and Hawley JA. Factors influencing running economy in trained distance runners. Sports Med. 2004; 34(7):465-85.

Thomas E, De Vito G and Macaluso A. Speed training with body weight unloading improves walking energy cost and maximal speed in 75- to 85- year old healthy women. J Appl Physiol. 2007; 103(5): 1598-603.

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Exercise and a family history of type 2 diabetes

© Kiankhoon | Dreamstime Stock Photos
© Kiankhoon | Dreamstime Stock Photos

Type 2 diabetes is more and more frequent in our Western world. It is probably the result of a complex and not- well-understood interaction of genes, lifestyle and obesity.

The disease starts with insulin resistance, which means that your tissues do not respond that well to stimulation by insulin. However, insulin is essential for the transfer of glucose from your blood into your tissues. As your tissues become resistant, you need more insulin to do the same job as before. If moreover the producing cells become dysfunctional, you will not be able to produce enough to keep your blood glucose levels normal and you will develop diabetes.

A family history of the disease is an important risk factor. Fortunately, you can lower your risk by exercising regularly. Working out will help you to normalise your glucose metabolism, as during exercise your muscles can take up glucose without insulin. It will also help you to keep your weight under control and reduce your risk of cardiovascular disease, which is diabetes’ major complication. Exercise is therefore a cornerstone of the prevention as well as of the treatment.

As exercise is so important for people at risk, the obvious question is: do people with and without a family history have different aptitudes for sport? To answer this, Antonio Bianco and his colleagues compared the aptitude for anaerobic performance of 33 elite athletes without a family history of type 2 diabetes with 13 elites with a family history.

The anaerobic metabolism is the pathway to produce energy without oxygen, as opposed to the aerobic metabolism. It is much quicker, but it is less economical than the aerobic metabolism, and your body will therefore use it for short, high intensity activities such as high intensity interval training and strength exercise.

The athletes performed squat jumps and a Wingate test*, which is the classical test to determine somebody’s peak anaerobic power.

As suspected, the athletes with a family history had a higher body mass than the others, but, surprisingly, their anaerobic performances were significantly better.

The majority of the studies showing the importance of regular workouts for diabetes used aerobic exercise. However, a mounting amount of evidence suggests that strength exercise is just as beneficial. If Bianco is right, his findings would be important for everybody who has a family history of type 2 diabetes, since it is likely that you will prefer an exercise discipline you are good at.

In other words: if you have a family history of type 2 diabetes, you might be better at sports that include shorter period of intense activity and/or power (e.g. most ball sports, gym work) than at endurance sports (e.g. distance running, walking). Maybe you would you therefore prefer them?

The most important thing is that you love your chosen form of exercise so much that you keep doing it!

*A Wingate test is performed on a specialised ergometer. After warming-up, the athlete starts pedalling as fast as possible. After three seconds the researcher adds a resistance corresponding to 75g/Kg of the athlete’s weight to the flywheel. The athlete continues to go as hard as possible for 30 seconds, and the researcher notes the peak power output.

Disclaimer: If you are new to exercising, please ask your doctor for advice first.This article is for general information only, and does not replace medical advice. It cannot be used to diagnose or guide treatment. If you have any concerns or questions, you should talk to a qualified health provider.

References and further reading:

A Bianco, F Pomara, M Raccuglia et al. The relationship between type 2 diabetes family history, body composition and blood basal glycemia in sedentary people. Acta Diabetol. 2014; 51(1): 79-84.

A Bianco, F Pomara, A Patti et al. The surprising influence of family history to type 2 diabetes on anaerobic performance of young male elite athletes. Springerplus. 2014; 3: 224. doi: 10.1186/2193-1801-3-224. eCollection 2014.

R Khardori, G T Griffing, B E Brenner et al. Type 2 Diabetes Mellitus. Medscape (Accessed on 5/10/2014).

R J Wood and E C O’Neill. Resistance training in type II diabetes mellitus: impact on areas of metabolic dysfunction in skeletal muscle and potential impact on bone. J Nutr Metab. 2012; doi:10.1155/2012/268197.  (Accessed on 5/10/2014).

Strength after endurance or endurance after strength training?

All endurance athletes (runners, cyclists, cross-country skiers…) need some strength training. Personally, I prefer to train for endurance and strength on separate days, but for many of us it is more time-effective to combine the two in one session. If that is your case, what do you do first?

© Phil Date | Dreamstime Stock Photos
© Phil Date | Dreamstime Stock Photos

This is an important question, as research has shown that endurance and resistance training lead to different adaptations. Strength training leads to increased muscle mass, while endurance training will allow you to use the available energy and oxygen more effectively and exercise for longer. If you combine both in one session, you will not have any recovery between them and it might be impossible for your body to benefit fully from both. If so, the order in which you do them (first endurance and then strength or the other way around) is important.  Getting it wrong could make a big difference.

Most, if not all, runners I know will start by endurance exercise, and according to Moktar Chtara and his colleagues that is indeed the right thing to do. They divided 48 young men in five groups. The first group performed endurance training only, the second strength training only, the third endurance plus strength and the fourth strength plus endurance workouts. The fifth group did not train and served as a control group. After 12 weeks the endurance plus strength group outperformed every other group during a 4 km run time trial, and their VO2max had improved most.

In the September issue of Medicine & Science in Sports and Medicine however, Moritz Schumann and colleagues published a study suggesting that this does not matter for cyclists. They divided 34 young men in two groups, one of which performed endurance plus strength workouts and the other strength plus endurance. The endurance part of the sessions consisted of cycling, and the strength part of exercises for all the major muscle groups but mainly for the legs.

Both groups improved in strength, VO2max and time to exhaustion, but after 24 weeks there were no significant differences between the groups. The researchers concluded that as endurance cycling is biomechanically similar to many of the strength exercises, they could enhance each other’s effect. Running is of course different.

Surprisingly, Schumann could not notice any significant reduction in body or visceral fat, or in cholesterol levels. Studies whereby the participants perform strength and endurance workouts on separate days on the other hand, typically do show improvements.  The researchers could not really explain this discrepancy: did the participants not train frequently enough (as they did two sessions worth in one go)? Only further studies can figure this out…

In the meanwhile, I’m going to continue planning my endurance and strength workouts in separate days.

References

M Chtara. K Chamari, M Chaouachi et al.  Effects of intra-session concurrent endurance and strength training sequence on aerobic performance and capacity. Br J Sports Med. 2005; 39:555-560.

GA Nader. Concurrent strength and endurance training: from molecules to man. Med Sci Sports Exerc. 2006; 38(11):1965-1970.

 M Schumann, M Kuusmaa, RU Newton et al.  Fitness and lean mass increases during combined training independent of loading order. Med Sci Sports Exerc. 2014; 46(9): 1758-1768.

Sleep enough to keep slim

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© Peter Elvidge | Dreamstime Stock Photos

 More and more people are overweight or obese and at the same time more and more people do not sleep enough. Could there be a link? Scientists have studied this problem by asking participants to reduce their sleep, usually from 8.5h/day to 5.5 h/day. They then noted what and how much the participants ate, and measured any hormone or body weight changes. Most of them would now answer yes indeed, there is a link.

It is clear that nobody believes that you can sleep excess weight off, but not sleeping enough (less than 7 hours/day) can hamper your efforts to slim down or keep your weight under control.

At a first glance this looks unbelievable, as when you are awake for longer, you are going to spend more energy.

The energy you spend consists of 3 components:

1) what you need to keep your body going (your basic metabolic rate),

2) the amount needed to assimilate food,

3) the energy used for all kinds of exercise and activities.

When asleep, you will not eat or move and your basic metabolic rate is reduced by 20-30%. Scientists have calculated that sleeping 5.3h instead of 8h would increase the amount of energy you spend by 45 kcal/d.

However, it is here that your unconscious brain starts interfering. As we have seen in some previous posts (e.g. here or here), your brain wants to keep you safe and it therefore wants your energy balance to remain the same. The balance between the energy you take in and the energy you spend determines your body weight, and depends on genetic, psychological and behavioural factors. Even if it sets your body weight a bit too high for your health, your brain will be unwilling to change it, as anybody who has ever tried to lose weight knows only too well.

Experiments have shown that when you have not slept enough, your brain will stimulate you to eat more to compensate for the energy you have spent. Unfortunately, it will make you overdo it. It will do so by making food more rewarding, and the data show that you will tend to snack more and to choose more fatty and carbohydrate-rich food. This is easily done in our modern world where food is widely available.

© Remigiusz Oprzadek | Dreamstime Stock Photos
© Remigiusz Oprzadek | Dreamstime Stock Photos

It is easy to see how all this will put your best efforts to stay slim in jeopardy. Moreover, a study by Arlet Nedeltcheva showed that dieters who slept for only 5.5 h/day lost more lean body mass and less fat than dieters who slept for 8.5h. They also suffered more from hunger.

Researchers have also studied the effect of insufficient sleep on next day’s activities. Even though some of them have not observed any effect, most report more sedentary time and less vigorous workouts. The discrepancy might be due to the fact that some study participants were used to insufficient sleep, or to the short duration of some studies which could not capture the full effect on people who exercise a few times a week.

There are still plenty of questions to be answered, e.g. what is the effect of habit, is there a difference between men and women, is what scientists observe in a study the same as what happens in real life etc…We do not know either what the effect of physical exercise is: regular exercise improves your sleep, which would then influence your energy balance. Nevertheless, it is a good idea to make sure you have enough sleep!

 

References

JP Chaput and MP St-Onge. Increased food intake by insufficient sleep in humans: are we jumping the gun on the hormonal explanation? Front Endocrinol (Lausanne). 2014; Jul 15;5:116. doi: 10.3389/fendo.2014.00116. eCollection 2014 (accessed 26/08/2014).

A V Nedeltcheva, J M Kilkus J Imperial et al. Insufficient sleep undermines dietary efforts to reduce adiposity. Ann Intern Med. 2010; 153(7): 435-441.

P D Penev. Update on energy homeostasis and insufficient sleep. J Clin Endocrinol. Metab. 2012; 97(6): 1792-1801.

MP St-Onge. The role of sleep duration in the regulation of energy balance: effects on energy intakes and expenditure. J Clin Sleep Med. 2013; 9(1): 73-80.

A cold drink to exercise in the heat?

Could consuming cold drinks or ice slush during workouts in the heat help you to perform better? Scientists have been wondering this for many years.

Theoretically it makes sense: as your brain’s main objective is to keep you safe, it will force you to slow down or even stop if it presumes that your core temperature could increase to dangerous levels before the end of the workout. Anything that helps you to keep your core temperature down is thus beneficial, and as cold drinks could act as a heat sink they could be helpful indeed. Scientific studies however, have been inconclusive.

© Dnally | Dreamstime Stock Photos
© Dnally | Dreamstime Stock Photos

Florence Riera and her colleagues have just published the latest study about this problem in PlosOne. They compared the effects of a cold (3 C), ice slush (-1 C) or neutral drink (23 C) with or without menthol flavouring on the performances of 12 trained male cyclists in hot and humid conditions.

The cyclists were randomly assigned a beverage and performed a 20 km time trial in the lab, which means that each of them did the test 6 times (once with each beverage). The performance was better using ice slush whatever the aroma, and better with menthol whatever the temperature. Ice slush or cold water with menthol flavouring was therefore the best.

The researchers concluded that a cold or ice slush drink interferes with the rise in core temperature, allowing you to exercise harder without – or with a smaller- increase in core temperature. 

Menthol usually provokes a sensation of freshness, it is a bit stimulating and it improves the airflow (that is why you use menthol lozenges when you have a cold), but exactly how it works is unknown.

Drinking ice slush is probably possible when you are cycling on a turbo trainer or in the gym, but what can you do if you are a road cyclist? You could try to cool down your core in advance, and researchers have shown that ice vests or cool water baths are helpful indeed.

Pre-cooling techniques are usually unavailable for recreational athletes, but cold drinks can easily be obtained before the start of any event. Christopher Byrne and his colleagues therefore wanted to find out if you could pre-cool yourself with cold drinks.

Seven male cyclists ingested 900 ml cold (2 C) or neutral (37 C) water over 35 minutes before cycling as many kilometres as possible for 30 minutes in a lab. When the athletes drank cold water they cycled 2.8% further and their core temperature (as estimated by rectal temperature measurements) was lower at the end of the test. They felt really cold before starting off though, and one of them was even shivering. Most of them needed to urinate before the exercise. Probably not a very pleasant experience….

© Denise Scott Jackson | Dreamstime Stock Photos
© Denise Scott Jackson | Dreamstime Stock Photos

I wonder if this kind of pre-cooling is possible for runners, as such a large amount of fluid is likely to create gastro-intestinal discomfort? I guess that the only thing runners can do is to get acclimatised and to accept that we will be slower…Or do you have a better idea?

References

C Byrne, C Owen, A Cosnefroy et al. Self-paced exercise performance in the heat after pre-exercise cold-fluid ingestion. J Athl Train. 2011; 46(6): 592-599.

 F Riera, TT Trong, S Sinnapath et al. Physical and perceptual cooling with beverages to increase cycle performance in a tropical climate. PLoSONE 9(8): e103718. doi:10.1371/journal.pone. 0103718. (Accessed 09/08/2014).

R Tucker. The anticipatory regulation of performance: the physiological basis for pacing strategies and the development of a perception-based model for exercise performance. Br J Sports Med 2009; 43: 392-400.

 Disclaimer: this article is for general information only, and does not replace medical advice. It cannot be used to diagnose or guide treatment. If you have any concerns or questions, you should talk to a qualified health provider.

Protein after resistance exercise

Do you need to take in extra protein after a strength exercise session and, if so, how much?
Scientists are still debating this question. It is an important one, even for endurance athletes, as we all need strength to practise our sport properly and to perform well. In the May edition of Sports Medicine, Stuart Philips from McMaster University has summarised what we know about this question.

© Milogu | Dreamstime Stock Photos
© Milogu | Dreamstime Stock Photos

Muscle proteins are in a constant turnover: some are broken down, and other are synthesised. As long as you making more muscle proteins than you are breaking down, your muscles will grow (hypertrophy) and you will get stronger, your performances will become better and, crucially for endurance sports, you will be able to maintain good form for longer and therefore reduce your risk of injury.

Resistance exercise will stimulate muscle protein synthesis for at least 24 to 48 hours. Proteins are made of amino acids, and having more amino acids in your blood will further enhance muscle protein synthesis. After a meal you tend therefore to make more proteins than you break down. The effects of eating and exercising reinforce each other, and this is why it is beneficial to have a protein rich drink or meal after your strength training session.

However, as exercise stimulates muscle synthesis for at least 24 hours, researchers such as Brad Schoenfeld and Alan Aragon believe that timing your meals is much less important than having enough protein in each of them. They think that supplements immediately after training are unnecessary as long as you are having a healthy diet containing enough protein. I have blogged about their opinions before.

There are 20 different amino acids, but our bodies can synthesise only 10 of them. The others are called the essential amino acids, as we have to get them from food. Unfortunately, we can only synthesise muscle proteins if all the essential amino acids are available, which means that we need a well balanced diet. One of them, leucine, is particularly important, as it triggers the synthesis. Foods that contain plenty of leucine, such as whey, are therefore more effective than others to build up muscles.

Working Up Sweat (ID: 74747)
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How much?

Having too much protein in your food does not help. The maximal effective amount is 0.25g protein/Kg body mass in younger people. Ageing and inactivity makes it harder to get the process of muscle synthesis started, and it is likely that we need more leucine and protein in our food as we get older. Older people may need up to 40g protein/ Kg body weight.

The rate at which the amount of amino acids rise in your blood is also important: a low level or an almost continuous delivery is much less effective than a bolus every three hours or so, as you would get from meals and snacks during a normal day.

Other components

– As yet, there is no evidence that other amino acids such glutamine or arginine, help to build up muscle.

– Carbohydrates are important to replenish your glycogen stores, but there are no reasons to believe that they influence muscle synthesis, as long as you have enough protein in your food.

In practice

Try to have at least three well balanced meals and/or snacks a day, each of which should contain sufficient protein, and schedule your workouts so that you finish before a meal. Do not eat too much protein either, as this is probably just wasteful.

As you get older, you will need more protein, especially more leucine. You will find a list of foods containing leucine by clicking here.

Never give up exercising, as inactivity and ageing are a bad combination for your muscles.

Disclaimer: this article is for general information only, and does not replace medical advice. It cannot be used to diagnose or guide treatment. If you have any concerns or questions, you should talk to a qualified health provider.

References

SM  Philips. A brief review of critical processes in exercise-induced muscular hypertrophy. Sports Med. 2014; 44 (1): 71-77.

BJ Schoenfeld,  A A Aragon and J W Krieger. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. J Int Soc Sports Nutr. 2013; 10 (1): 53.