Tag Archives: inactivity

Muscle strength gains during resistance exercise training are attenuated with soy compared with dairy or usual protein intake in older adults – part 1

Share this:

On a global scale, the number of people over 60 yr is expected to more than double from 841 million in 2012 to more than 2 billion by 2050. This change in demographics will have profound implications for many aspects of life (Thomson et al. 2016). Furthermore, Government bodies worldwide will be faced with considerable challenges related to ageing policy and how best to deal with this new reality.

ageing, loss of muscle mass, strength, sarcopenia
Courtesy @LeighBreen PhD (Twitter): Sarcopenia presentation

Of the many things that occur during the ageing process one of the most obvious signs is the loss of skeletal muscle mass and strength, with decrements in physical function and potential predisposition to disability. In academic speak, this is known as sarcopenia. The research and interest in this area has been gradually increasing as evidenced by the below graph that shows – since the term sacropenia was first coined in 1989 – a massive increase has occurred. To enhance functional physical capacity and reduce disability into older age, it is therefore critical to develop strategies that facilitate the attenuation of skeletal muscle mass and strength. With more than 30 years of scientific evidence to show that exercise – and, more specifically, resistance training – as both very effective and safe methods to maintain skeletal lean muscle tissue mass and strength (see here and here), current recommendations strongly advocate this form of exercise for older adults.

Interestingly, gains in skeletal lean muscle tissue and muscular strength may be potentiated through the application of appropriate nutritional strategies and in particular increased protein intake. A recent meta-analysis by Cermak and colleagues (2012) reported ~35% greater enhancement in muscle mass and strength can be achieved in older adults undertaking resistance training who consumed at least 1.2 g/kg of body weight/d of protein through supplementation or diet compared with other control groups that were either non-protein, lower protein diet or exercise training with no nutrition co-intervention. Thus, protein quality or source may further augment the effect of the resistance training stimulus by eliciting a greater stimulatory effect on muscle protein synthesis. Dairy protein compared to soy protein has been shown to be more effacacious post-exercise in stimulating increases in lean mass in young healthy males. In older adults though this response to resistance training and increased protein intake may be blunted which necessitates that higher doses of protein are required to bring about an increase.

The aim of the study under review for this article was to determine whether increased dairy or soy protein intake combined with resistance training improved strength gains in older adults.

Soy protein, strength, muscle mass, testosterone
Does Soy Protein Suppress Strength Gains?

Researchers recruited one hundred and ninety two older adults (age, 50-79 yr; BMI, 20-35 kg/m²) by public advertisement. Participation was allowed if they were physically active but not engaged in formal exercise. Those that meet the inclusion criteria undertook a resistance training program for 12 weeks. Randomisation to one of three experimental diets was performed:

  1. High dairy protein diet (HP-D)
  2. High non-dairy (soy) protein diet (HPeS)
  3. Usual protein diet (UP).

DIET: Each diet was isocaloric and low-fat (30% fat, <8% saturated fat) and aimed to maintain energy balance. The diets provided ~1 g/kg of body weight/d of dietary protein, mainly from lean meat sources. HP-D including additional dairy protein of ~27 g per day in the form of a shake (475 g Devondale Smart reduced fat milk, 200 g Nestle Soleil diet no fat yoghurt & 20 ml Bickfords vanilla milk mix syrup). The HP-S providing in the form of a shake – 300 g So Good reduced fat soy milk, 100 g Kingland soy yoghurt, 20 g Nature’s Way instant natural protein powder & 15 g poly-joule – which added an extra ~27 g of soy protein. Protein intake was distribtuted evenly across the day with the three main meals providing >20 g per feed; this is consistent with best practice for optimising muscle protein synthesis in older adults. Following resistance training sessions participants consumed the appropriate additional foods immediately after training and that represented the main meal of that day. Participants were supplied with key foods specific to their allocated diet for the duration of the study to facilitate adherence. Energy and macronutrient intakes from daily food checklists were analysed to monitor food intake and dietary compliance.

Strength training and ageing
Resistance training: a key component of healthy ageing?

RESISTANCE TRAINING: All subjects participated in a whole body resistance training program three days per week on non-consecutive days for 12 weeks and the principles of progressive overload were applied.  Five exercises on weight stack pin loaded machines were performed: leg press, chest press, knee extension, lat pull down and leg curl, and seated bent knee hip flexions. Trainees started with one set x 8 repetition maximum (RM; maximum weight lifted for eight repetitions), this was maintained until individuals could perform three sets of 12 repetitions and then the load was increased. This cycle was repeated again for the duration of the trial. Assessment of muscle strength, body composition, physical function and quality of life was conducted at baseline and 12 weeks. All exercise training was completed in the research gymnasium at the University of South Australia under the supervision of gymnasium staff.

Assessment of muscle strength using handgrip, isokinetic dynamometry and 8RM was completed. The leg press, chest press, knee extension, lat pull down and leg curl were tested with 8RM and a summed total 8RM for all exercises was recorded  Dominant handgrip strength was measured using hydraulic handgrip dynamometer and isometric strength of the knee extensor muscles of the right leg was assessed using an isokinetic dynamometer.

resistance training slows down aging
You don’t have to lift weights to do resistance training

RESULTS: 83 participants completed the intervention being adherent to both diet and resistance training protocols. HP-D and HP-S had higher protein intakes compared with UP (HP-D 1.41 ± 0.14 g/kg/d, HP-S 1.42 ± 0.61 g/kg/d, UP 1.10 ± 0.10 g/kg/d; P < 0.001 treatment effect). Baseline characteristics, compliance with the intakes of the additional protein foods and adherence to the resistance training program in those that meet all relevant study protocols was not different between groups.

Increase in muscular strength as ascertained by total 8RM was significantly less in HP-S compared with HP-D and UP (HP-D 92.1 ± 40.8%, HP-S 63.0 ± 23.8%,UP 92.3 ± 35.4%; P=0.002 treatment effect). 8RM percent improvement in leg press was much greater in HP-D and UP compared with HP-S (HP-D, 136.8 ± 88.2%; HP-S, 64.8 ± 35.2%; UP, 135.0 ± 62.0%; P < 0.001). For most other exercises, 8RM was not signficantly different for each diet group. Total training volume over the 12 weeks was not different between groups.

Weight, waist circumference and total body fat decreased and lean mass and the distance covered during the 6 min walk test increased significantly increased with no difference between diets. As expected absolute protein intake (g) and relative protein intake (per kg body weight) were different with HP-D and HP-S greater than UP. Dairy protein in HP-D was significantly greater compared with both HP-S and UP with the amount of non-dairy protein in HP-S significantly greater compared with both HP-D and UP.

DISCUSSION: This study has demonstrated that 12 weeks of progressive resistance training exercise in healthy older adults did not provide any additional benefit for improvements in strength, body composition, physical function, or quality of life when additional protein from either dairy or soy is compared to usual (lower) protein intake. Perhaps of more significant interest is that results suggested that increased soy protein intake attenuated improvements in muscular strength. I am going to publish this article before it is entirely finished as I believe this is important research for those interested in this area and facilitating discussion on this topic should start now.

image
Stay strong and prosper

Over the next week or so I will be posting a part 2 in relation to this study as there is a lot more to explore. For example, why did the authors fail to acknowledge or discuss the fact that the attentuated strength improvement in the HP-S was confined exclusively to the leg press exercise? For all other exercises, no difference for dietary influence on strength improvement was found. Whilst not a criticism, it seems rather odd that whey protein was not included as one of the intervention dietary arms of the study. The evidence for whey protein augmenting the development of strength and facilitating the accretion of lean muscle mass from resistance training is well documented. Comparing this with the other diets would have provided some interesting insights into whether there are any further benefits of whey protein to older adults. Finally, one thing that does disappoint me about many of the studies that investigate the efficacy and safety of resistance training in older adults is the reliance on exercises that are machine-based.

CONCLUSION: Increased soy protein intake attenuated gains in muscle strength during resistance training in older adults compared with increased intake of dairy protein or usual protein intake.

Look out for part 2 (see here) titled “Does Soy Protein Really Inhibit Resistance Training Induced Strength Gains In Older Adults?” where I will discuss some of the things I mentioned above in more depth and some possible mechanisms of action as to why soy protein may or may not suppress strength gains from resistance training.

Post-script: Following further analysis and publication of part 2 of this blog, I wrote a letter to the Editor of Clinical Nutrition Journal outlining some of the, what I believed, flaws regarding the interpretation of the results of this trial. Upon peer review this was accepted for publication and can be found here. If you are unable to access this correspondence and the authors reply to my letter, please contact me and I should be able to assist. 

References

Cermak et al. (2012) Protein supplementaiton augments the adaptrive response of skeletal muscle to resistance-type exercise training: a meta-analysis Am J Clin Nutr 96: 1454- 64.

Thomson et al. (2016) Muscle strength gains during resistance exercise training are attenuated with soy compared with dairy or usual protein intake in older adults: A randomized controlled trial. Clinical Nutrition. 35: 27-33

Wilson, SA (2016) Comment on: Muscle strength gains during resistance exercise training are attenuated with soy compared with dairy or usual protein intake in older adults: A randomized controlled trial. Clinical Nutrition. 35(6):1575-1576


Disclaimer: All contents of the FitGreyStrong website/blog are provided for information and education purposes only. Those interested in making changes to their exercise, lifestyle, dietary, supplement or medication regimens should consult a relevantly qualified and competent health care professional. Those who decide to apply or implement any of the information, advice, and/or recommendations on this website do so knowingly and at their own risk. The owner and any contributors to this site accept no responsibility or liability whatsoever for any harm caused, real or imagined, from the use or distribution of information found at FitGreyStrong. Please leave this site immediately if you, the reader, find any of these conditions not acceptable.

© FitGreyStrong


Share this:

Is high-intensity resistance training bad for your heart?

Share this:

“Intense resistance training without adequate aerobic endurance exercise may not be good for your cardiovascular health” FitGreyStrong 2019

The aorta (the largest artery in the body and that which sits at the top of the left ventricle, the heart’s muscular pumping chamber) can be assessed for arterial stiffness (the stiffer it is, the worst the prognosis) via a non-invasive test called Aortic Pulse Wave Velocity (usually measured in meters per second). Basically, the quicker the speed, the higher the stiffness, and stiff arteries are not healthy ones so it is important to establish what and if certain types of exercise improve aortic pliability and thus reduce chances of cardiovascular disease.

In 2009 Japanese researchers showed that increased aortic pulse wave velocity was able to predict cardiovascular mortality in middle-aged and elderly Japanese men (see here). What this suggests is that pulse wave velocity is a powerful measure of cardiovascular health.

Scientists investigating the effects of aortic pulse wave velocity in endurance trained athletes, intense resistance trained athletes and sedentary individuals discovered that much lower values were recorded for those doing endurance exercise versus both resistance trained and sedentary. In fact, the pulse wave velocity of the resistance trained athletes was similar to those sedentary. As such, intensive resistance training only may not be particularly effective for optimising cardiovascular health (see here).

It could be argued that the athletes involved in this study were weightlifters and the training involved in such a sport is very specific and possibly somewhat different to the sort of resistance training performed by many recreational lifters/trainees (i.e. higher reps, shorter rest periods that would provide greater cardiovascular stimulation and hence more likely improve arterial stiffness).

 However, the takehome message from FGS is that if you are looking to improve fitness, health and wellness, make doubly sure you include a decent amount of aerobic exercise or training into your week alongside your must-do resistance/strength.


For local Townsville residents interested in FitGreyStrong’s specialised Exercise Physiology services or exercise programs for older adults or for Master’s competitors wanting to enhance athletic performance, contact FitGreyStrong@outlook.com or phone 0499 846 955 for a confidential discussion.

For other Australian residents or oversees readers interested in our services, please see here.


Disclaimer: All contents of the FitGreyStrong website/blog are provided for information and education purposes only. Those interested in making changes to their exercise, lifestyle, dietary, supplement or medication regimens should consult a relevantly qualified and competent health care professional. Those who decide to apply or implement any of the information, advice, and/or recommendations on this website do so knowingly and at their own risk. The owner and any contributors to this site accept no responsibility or liability whatsoever for any harm caused, real or imagined, from the use or distribution of information found at FitGreyStrong. Please leave this site immediately if you, the reader, find any of these conditions not acceptable.


© FitGreyStrong

Share this:

Weight Loss Advice: Be Very Careful Who You Trust

Share this:

FitGreyStrong observation:

The mass media and ‘rogue’ researchers are confusing the public by suggesting that exercise does not facilitate weight loss. Sensationalised, poorly researched and inaccurate media presentations have misled consumers because a thorough assessment of the evidence wasn’t undertaken. Some sports scientists and doctors have further exacerbated the problem by claiming that physical inactivity does not contribute nor is associated with becoming overweight or obese.

FitGreyStrong Advice:

Be extremely careful about making any changes to your exercise, lifestyle, dietary, supplement or medication regimens based on information produced through the media. Consult competent health care experts with recognised qualifications and good reputations, do your own research, talk to those you trust and use some good old commonsense before making any changes.

For those interested in wanting to know more on this topic please continue reading see below.


For local Townsville residents interested in FitGreyStrong’s Exercise Physiology services or exercise programs designed to achieve the above-mentioned benefits or to enhance athletic performance, contact FitGreyStrong@outlook.com or phone 0499 846 955 for a confidential discussion.

For other Australian residents or oversees readers interested in our services, please see here.


Exercise, weight loss and why it doesn’t work for everybody

The following article represents the first of a series of blogs that will explore the reasons behind why exercise may fail as a weight loss strategy. It is often assumed that when someone starts an exercise program, weight or body fat loss will happen naturally and almost by accident. However, recent research demonstrates that the magnitude of individual weight loss varies dramatically, with some losing a substantial amount of weight, others maintaining weight and a few actually gaining weight. The question is, how is this possible? What compensatory mechanisms are at play to negate the effectiveness of exercise?

In this first installment I want to discuss how the mass media and ‘rogue’ researchers have contributed to the unfortunate situation where the message about the efficacy of exercise has been obfuscated and distorted. As a result the general public have received mixed messages as to whether exercise has any role to play in weight loss at all. Some sections of the media have done a pretty good job at cherry-picking research or commentators that promote the idea that exercise is largely ineffective when it comes to weight loss. This has contributed to the public perception, then, that exercise may have limited usefulness as a method to facilitate weight loss.

One of the best examples of this occurred when the Australian Broadcasting Corporation’s (ABC) TV show, Catalyst, aired a segment called “Toxic Sugar” (see here) claiming that:

“The studies show that exercise has virtually no effect on weight loss. One thing exercise does is it makes people hungry.”

weight loss and the media
Are the media trustworthy?

Such sweeping claims – that are not based on the actual scientific evidence – are particularly worrisome given the impact that such high-rating TV shows may have on the lifestyle choices and behaviour of their viewers. Why such organisations would besmirch the value of exercise is an interesting conundrum that has no easy answers.

There are a few possible reasons why this has happened and they are by no means based on any evidence I have been able to dig up and for this I apologise. The speed of the 24/7 news cycle, nevertheless, in conjunction with the need to sensationalise stories and news segments in an effort to gain viewer attention and watchership, have more than likely played a part. Media outlets do not undergo any critical assessment from any independent body – either internally or externally – to corroborate the accuracy of their program’s content. They can therefore function with relative impunity and little accountability. Media outlets are consequently free to make – without fear or retribution – poorly researched and misleading radio or TV shows that may not be in the public’s best interests.

Another reason why the media may produce content that is inaccurate and misleading is a simple one. Basically, the research that has gone into producing a show or print article has been hasty and superficial without a thorough review of the scientific evidence. If you consider the Catalyst segment mentioned above it was so lopsided because of one key component that was missing from the show – an opposing voice. The report ended up being totally biased because it did not present – in an objective manner – robust and contradictory scientific evidence. It also failed to interview any expert commentators that hold serious doubts about many of the claims that were aired.

The public’s confusion regarding the role of exercise in facilitating weight loss was further compounded, after well respected, credentialed doctors and sports scientists suggested in the British Journal of Sports Medicine that physical inactivity and obesity was a myth. Authors Malhotra and co in their editorial titled “It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet” (see here) made one of the most contentious claims in decades by suggesting that increasing obesity rates were not related to changes in physical activity levels. To put it another way, what they were essentially saying is this:

Doing no physical activity and sitting on your arse all day does not contribute to your risk of putting weight on or becoming obese!!

Here’s an interview on ABC’s Lateline with one of the authors, Dr Aseem Malhotra, discussing this publication (see here) if you are interested in listening to some of the commentary on this.

Let’s now just take a look at exactly what was put to print, so you the reader, can judge whether or not I am justified in being perplexed by their editorial. In it they state:

“Regular physical activity reduces the risk of developing cardiovascular disease, type 2 diabetes, dementia and some cancers by at least 30%.”

Fine, that’s dandy, I’m definitely happy with that! They continue:

However, physical activity does not promote weight loss (my emphasis). In the past 30 years, as obesity has rocketed, there has been little change in physical activity levels in the Western population” (p. 1).

Criterium racing
Exercise and physical activity doesn’t promote weight loss?

This claim was based on one paper (see here) published in 2013 by Amy Luke and Richard S Coope (Department of Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, Chicago, USA) which theorised that energy expenditure changes over the 20th century could not explain the increased obesity levels that now exist in the West and increasingly so in developing countries.

Such assertions fail to take much notice of a hefty amount of research that has shown that for many, exercise is a very effective method for assisting weight loss (see here and here). So it is rather puzzling why a more balanced and nuanced account of our current understanding of exercise and weight loss was not undertaken by these authors. So just what did they ascribe the increasing rates of obesity to? Answer: Excessive carbohydrates and sugar. Now this is certainly an interesting hypothesis and one that will unfortunately require another blog to give this topic justice so you’ll have to wait for that one. What I will say though is that such examples truly exemplify the problems of intelligent, educated researchers entrenching themselves in a paradigm of thinking so deeply that any evidence to the contrary is either dismissed or diminished.

Anyway, following publication of this editorial the global media jumped on it. If you Google the title of their article you’ll notice the massive media coverage it received across all forms – print, broadcast and the internet. Social media like Facebook and Twitter picked up on it and the core message – that physical activity and exercise does not promote weight loss – was repeated ad nauseam. There was a harsh backlash from many corners – sports scientists, researchers, public health advocates and the like – but suffice it to say these criticisms and feedback did not generate any traction in the media nor were any corrective statements issued. The genie was out of the bottle and the message that exercise did not work for weight loss was left hanging in the air, slowly seeping and diffusing into the public’s consciousness. This just reinforces my earlier comments where the media over-sensationalise stories and news segments in an effort to gain viewer attention, watchership and market share. What seems apparent in my view, then, is that these organisations have expunged themselves of their ethical obligations to ensure that the public’s best interests are kept front and centre.

Perhaps not surprisingly there is research that contradicts the central plank of their argument which hinges on the notion that activity levels have remained static over the last 30 years. Church  and colleagues (2011) (see here) found that:

“since 1960 the estimated mean daily energy expenditure due to work related physical activity has dropped by more than 100 calories in both women and men. Energy balance model predicted weights based on change in occupation-related daily energy expenditure since 1960 for each NHANES (U.S. National Health and Nutrition Examination Surveys) examination period closely matched the actual change in weight for 40–50 year old men and women. For example from 1960–62 to 2003–06 we estimated that the occupation-related daily energy expenditure decreased by 142 calories in men. Given a baseline weight of 76.9 kg in 1960–02, we estimated that a 142 calories reduction would result in an increase in mean weight to 89.7 kg, which closely matched the mean NHANES weight of 91.8 kg in 2003–06. The results were similar for women.”

Based on these findings the increase in obesity levels – in the US at least – can be largely attributed to changes in energy expenditure via reductions in occupation-related physical activity rather than solely due to the over-consumption of carbohydrates and sugar as postulated by the editorial discussed above. The debate will probably continue to rage as to what the culprit is but logically it seems quite obvious that the answer lies between these two opposing explanations. So instead of it being purely diet-related or activity-related, the current obesity problem has probably come about because of simultaneous changes to both.

why doesn't exercise work for fat loss in everybody
Do your own research

To bring this to a close I would like to conclude by saying that certain sections of the mass media and ‘rogue’ researchers have undeniably contributed to the public’s confusion regarding the role of exercise for weight loss. Until such a time that all forms of media are more closely scrutinised and held accountable for the veracity of their productions, the advice from FitGreyStrong is to be very careful about making any changes to your exercise, lifestyle, dietary, supplement or medication regimens based on information accessed via the media. Consult competent health care experts with recognised qualifications and good reputations, do your own research, talk to those you trust and use some good old commonsense before making any changes.

To read the next installment of this series that summarizes some of the evidence supporting the idea that physical activity and exercise are important modulators of body fatness see Regular Exercise Doesn’t Promote Weight Loss: Fact or Fiction?


Disclaimer: All contents of the FitGreyStrong or FGS website/blog are provided for information and education purposes only. Those interested in making changes to their exercise, lifestyle, dietary, supplement or medication regimens should consult a relevantly qualified and competent health care professional. Those who decide to apply or implement any of the information, advice, and/or recommendations on this website do so knowingly and at their own risk. The owner and any contributors to this site accept no responsibility or liability whatsoever for any harm caused, real or imagined, from the use or distribution of information found at FitGreyStrong. Please leave this site immediately if you, the reader, find any of these conditions not acceptable.
©FitGreyStrong

Share this:

Resistance Training Alters The Trajectory Of Ageing

Share this:

Recently I published an article on my website titled:

“Strength training can alter the trajectory of ageing”.

After receiving feedback from some of those who regularly visit my website and social media channels, there were some suggestions to provide a summarised or bottom-line version of some of my articles for those that are looking for something that gets straight to the point. So here it is. The short version of the abovementioned article.

The research paper that everyone should read

The year was 1990 and researchers Maria Fiatarone and colleagues published their findings in The Journal of the American Medical Association after undertaking a study to determine the feasibility and the physiological consequences of high-resistance strength training in the frail elderly. These participants were very frail, had an average age over 90, suffered many co-morbidities and were basically not in very good condition. Their muscles were very atrophied, functional capacity was very poor and their physical movements were very slow.

After 8 weeks of progressive resistance training that only utilised one exercise that focused exclusively on the quadricep (thigh) muscles, the results were totally unexpected. Gains in muscle strength were impressive averaging over 170%, with some subjects making extraordinary gains of almost 400%. There was an accompanying increase is muscle size of over 10% as assessed by CT scans. Functional mobility accompanied the improvements in strength and muscle hypertrophy (growth). The time taken to complete the walking test improved substantially from 44 seconds to 29 seconds representing a 48% improvement. Two subjects no longer needed canes to walk at the end of the study and one of three subjects who could not initially rise from a chair without the use of their arms became able to do so. These physiological and functional changes were truly incredible.

What is clear is that the preservation of fat-free mass (muscle) as one ages is a critical factor and directly affects muscle strength in the older person.

Exercise and resistance training specifically, is able to provide the neuromuscular system the appropriate physiological stimulus to reverse and modify a portion of the muscle weakness often and simply put down to old age.

Re-read that sentence because this is huge! So off you go and start lifting.

For the longer version please see here.


Disclaimer: All contents of the FitGreyStrong website/blog are provided for information and education purposes only. Those interested in making changes to their exercise, lifestyle, dietary, supplement or medication regimens should consult a relevantly qualified and competent health care professional. Those who decide to apply or implement any of the information, advice, and/or recommendations on this website do so knowingly and at their own risk. The owner and any contributors to this site accept no responsibility or liability whatsoever for any harm caused, real or imagined, from the use or distribution of information found at FitGreyStrong. Please leave this site immediately if you, the reader, find any of these conditions not acceptable.
© FitGreyStrong
Share this: