Tag Archives: sedentary

Endurance, Exercise Physiology, Strength, Weight/Fat loss, Mobility

12 Reasons Why Older Adults Need To Do Resistance Training Exercise: Part 2

June 15, 2023 seanwilso 4 Comments

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In part 1 of “12 reasons why older adults need to do resistance training exercise” I outlined some of the benefits to health that have been shown to occur as a result of partaking in regular resistance training exercise. The scientific evidence supporting the inclusion of resistance training as part of a healthy lifestyle is now indisputable. Whilst improvement of health is an obvious goal of many older athletes, it is the enhancement of sports performance that drives many in a quest to remain competitive, both against fellow competitors, but also – somewhat egocentrically – against their younger self. Even if you aren’t an elite masters athlete these benefits as outlined below can be truly life-changing.

Resistance training exercise remains an integral component of programs of most elite sportspeople. Increased maximal strength and power developed through the application of progressive resistance training has been shown to improve performance above and beyond that achieved by limiting training to sports specific training. This is now recognised by sports scientists, exercise physiologists, strength & conditioning experts and coaches.

strength training for over 60 female — Resistance Training Improves Older Athletes Performance (Picture: Pixabay)

Of particular note for older athletes is that the performance benefits may be even greater than that of younger elite athletes. One of the hallmark changes to occur with age is the progressive loss of strength with significant atrophy or loss of skeletal muscle playing a significant role. This fundamental biological change that occurs with ageing manifests in a gradual deterioration of physical function and performance.

However, there is compelling evidence that the trajectory of this decline is modifiable and can be attenuated by lifestyle factors. The data to support regular exercise as a key factor in preserving skeletal muscle and physical function is overwhelming. Resistance training is one of the very best methods currently available for older adults and masters athletes to stimulate the physiological processes required to increase myofibrillar protein synthesis rates, skeletal muscle hypertrophy and muscular strength. These skeletal muscle adaptations lie at the core of why this type of exercise improves the functional performance of older adults and athletic performance of masters athletes.

The following 6 compelling reasons explain why resistance exercise should be included in all training programs of older adults where enhanced performance – for activities of daily living or sporting – are desired.

Enhance skeletal health. Stronger bones can handle greater training loads and transfer muscular forces more effectively and efficiently. Bone mineral density (BMD) decreases as we age however this can be slowed by regular physical activity and appropriate nutrition. Risk of musculoskeletal injury is increased when bone strength is decreased with age, especially during falls that can cause catastrophic consequences for some.

Resistance training has been shown to be quite a potent stimulus for improving bone mineral density. Some evidence suggests that plyometric-type or jumping activities also provide an excellent training method to stimulate significant and positive bone adaptation which yields increased BMD and therefore stronger bones.

Masters cyclists as a group are unfortunately at an elevated risk of reduced BMD (weaker bones) due to the non-weight bearing nature of cycling. It is strongly recommended that all masters cyclists – in fact, all cyclists – should perform adjunctive resistance exercise in their training program (see links 1, 2, 3, 4 & 5).

Maintain or increase lean body mass (skeletal muscle). Remember muscle is critical to both speed and endurance performance. From age 50 onwards muscle loss accelerates but there is a substantial amount of evidence that this is exacerbated by increased sedentarism (inactivity). Resistance training attenuates muscle mass loss.

Ageing is accompanied by reduced muscle mass and this has been mainly attributed to type II muscle fibre atrophy or reduction in size. It is unlikely that there is substantial muscle fibre loss however this remains to be elucidated. In older adults that have demonstrated substantial lean body mass loss and type II muscle fibre atrophy, prolonged resistance training has demonstrated significant increased muscle mass and this was shown to occur exclusively in type II muscle fibres. Nonetheless, some research has shown both type I and type II muscle fibre hypertrophy so more data is required to ascertain whether such things as age, gender, training status and training program parameters, affect muscle fibre changes and responsiveness to resistance training exercise (see links 1, 2, 3, 4, 5, 6).

Increased muscular strength, power and speed. Research investigating the effects of progressive resistance training programs demonstrate that muscle strength, power and speed improve, and in many case, quite impressively. In fact, even in nonagenarians, skeletal muscle strength and functional mobility assessed by a gait velocity test improved dramatically (>170% and 48% increase, respectively) after only 8 weeks of resistance training.

As mentioned above, the significant atrophy that occurs with age in fast-twitch type II muscle fibres, directly impacts performance of activities that require speed. Resistance training can reverse some of this decline, restore some of the lost contractile protein of these critical muscle fibres, increase maximum skeletal muscle strength and therefore elicit substantial improvements in movement speed of various specific sporting skills.

Older athletes that are avoiding or not adjusting their program to allow a little time to perform some resistance training exercise are missing out on some incredible benefits (see links 1, 2, 3, 4, 5).

Lose body fat and get leaner. As outlined above, skeletal muscle mass decreases significantly from age 50 with concomitant decreases in resting metabolic rate (RMR). RMR is the largest component of total daily energy expenditure (TDEE) accounting for 60-80%. Whilst reductions in muscle mass account for a significant proportion of the accommodating changes in RMR, decreasing organ mass and decreases to specific metabolic rates of individual tissues also contribute to the decrease in RMR.

These age-related changes in RMR reduce TDEE. This may contribute to increased adiposity as we grow older given that energy intake to maintain body mass decreases proportionally to the degree of reduction in RMR and TDEE. In other words, if dietary habits and energy intake remains constant over time but RMR and TDEE decrease subsequent to the loss of skeletal muscle, positive energy balance may ensue and fat mass may therefore naturally increase.

Resistance training is well known for stimulating muscle hypertrophy or increasing skeletal muscle mass and has been shown to elicit reductions in fat mass in obesity during ad libitum diets. In contrast, aerobic exercise-induced weight loss consistently leads to reductions in lean body mass and RMR which may make the propensity of rebound fat gain more likely.

Inclusion of resistance training exercise in programs of older athletes or non-athletes doesn’t guarantee that there will be body fat loss (nutrition and diet obviously play a key role) but it certainly makes weight management easier and supports weight loss efforts if modifying the diet in an attempt to get leaner. Much of the research that has investigated the utility of resistance training in older adults demonstrates that it is a very effective fat loss strategy when performed with other lifestyle-based interventions aimed at improving physical function and body composition (see links 1, 2, 3, 4, 5).

Improves endurance. Resistance training that is designed to increase muscle strength and power has been shown to improve endurance performance. More evidence exists to support such exercise in younger adult athletes as there has been limited research exclusively focused on older athletes.

Nonetheless, the research completed to date is strongly suggestive that resistance training enhances endurance in older athletes and non-athletes. A study conducted in 2010 demonstrated that strength training consisting of 10 sets of 10 repetitions of 1RM load, 3 minutes rest between each set, 3 times/week, increased both knee extensor maximal voluntary contraction torque and cycling efficiency. It is reasonable to postulate that had they utilised a program that incorporated more compound, complex, multi-jointed exercises such as squats and deadlifts – such that all major lower body muscle groups were strengthened – significantly greater cycling economical benefit would have been elicited.

When masters endurance runners were studied after following a resistance training program designed to increase maximal strength (4 sets of 3-4 repetitions at 85-90% of 1RM, two times per week), a significant improvement in running economy at marathon pace (6.1%) and dynamic leg strength (16.3%) was achieved.

It is proposed that the following training adaptations may facilitate endurance performance improvement:

the delayed use of the fast-twitch type II muscle fibers;
enhanced neuromuscular efficiency;
increased proportion of more fatigue-resistant fast-twitch type IIa fibres;
improved musculo-tendinous stiffness (see links 1, 2, 3).

Reduce injury risk. Regularly performed resistance exercise can minimize the musculoskeletal alterations that occur during ageing. It may also contribute to the health and well-being of the older population.

There is strong evidence that suggests such exercise can prevent and control the development of several chronic musculoskeletal diseases. Improvement of physical fitness, function, and independence in older people, plus successful management of musculoskeletal disorders, results in dramatic improvements in quality of life.

Stronger muscles, bones, connective tissue, ligaments and tendons mean our limbs and joints are more able to handle the rigours of training, competing and activities of daily living (see links 1, 2, 3, 4, 5).

In conclusion, based on the 12 reasons that I have explored which demonstrate profound benefits to both the health, functional and sporting performance of older athletes and non-athletes, resistance training is a must-do and should be a pivotal component of any exercise program.

To read “12 reasons why older adults need to do resistance training exercise: part 1” that explores the health-related benefits in older adults see here.

For local Townsville residents interested in FitGreyStrong’s Exercise Physiology services or exercise programs designed to achieve the 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.

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

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Weight/Fat loss, Exercise Physiology, Nutrition

Regular Exercise Doesn’t Promote Weight Loss: Fact or Fiction?

June 28, 2022 seanwilso 3 Comments

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Several years ago researchers and authors Malhotra, Noakes & Phinney published an article in the British Journal of Sports Medicine titled:

“It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet” (see here)

This created quite a storm in several fields of scientific research including many fitness and nutrition blogs. It was lambasted by some though as inaccurate and misleading – just Google the title of the article and you’ll understand what I mean. Essentially, their article claimed that regular physical activity does not promote weight loss and that excessive consumption of carbohydrates, in particular, sugar, is the primary cause of the obesity epidemic. Whilst excessive sugar consumption has played an important role in exacerbating the obesity crisis, it would be naive and short-sighted to suggest that this is the be-all and end-all in explaining society’s current predicament.

More recently Julia Belluz and Javier Zarracina published (April 2016) an article at Vox titled:

“Why you shouldn’t exercise to lose weight, explained with 60+ studies” (see here)

This article posits that exercise is unhelpful for weight loss and makes very similar claims to the Malhotra et al. paper. Of course, the real question is, are these claims valid? Could it really be true that weight loss is not facilitated by increasing daily energy expenditure and exercise? I think the answer to these questions are not black or white. My main concern with the articles mentioned above is that they are rather myopic, polarising and do not provide a fair and balanced assessment of the current evidence.

Instead, the evidence published to date demonstrates that ‘our’ increasing waistlines are closely related – but not confined to – the interaction of the following 3 factors. Firstly, the sum total of all physical movement performed whilst awake has substantially decreased over the last 50 years. Secondly, activities of a sedentary nature have dramatically increased. What are you doing right now? Thirdly, total energy intake over the last 50 years has continued to increase over and above total daily energy expenditure requirements. If movement levels are low and energy intake high – irrespective of where the excess is derived from – body weight, body fat and BMI will naturally increase. But does increasing physical activity levels via a formalised exercise program and/or non-exercise based physical activities (e.g. leisure time movement, domestic chores/activities) facilitate weight loss by increasing total daily energy expenditure? The answer to this is yes and no.

Today I want to focus on the evidence that was accessible following a brief Google Scholar search that supports exercise as well as other non-exercise increases in daily physical movement as being promoters of weight loss. For anybody not familiar with Google Scholar (https://scholar.google.com.au), it is a search engine by Google that searches for only published, peer-reviewed journal-based research and consequently provides information that is evidence-based rather than ‘opinion-based’ which is largely what would be accessed via Google, Yahoo or any other search engine. So, what did I find?

One of the more interesting pieces of research that directly contradicts the article by Malhotra and co. is that written by Church et al. (2011). They concluded that over the last 50 years in the U.S., daily occupation-related energy expenditure was estimated to have decreased by more than 100 calories per day, and this reduction in energy expenditure could account for a significant portion of the increase in mean U.S. body weights for women and men. What this would suggest is that rather than increased obesity rates being caused exclusively by too many carbs or too much sugar, as argued by the “you can’t outrun a bad diet” article, the current problem has been driven by large reductions in energy expenditure due to changes to occupation-related physical movement. In other words, we have transitioned from jobs that are active and require a lot of physical movement to jobs now that have most of us sitting on our backsides for hours on end.

Work places changes to physical activity — Doing this all day can’t be helpful

Previous reports based on estimated caloric consumption from food production and food disappearance (food waste) estimates have concluded that increased caloric consumption could account for most, if not all, of the weight gained at a population level in the U.S. Nonetheless, a recently validated differential equation model was used to identify a conservative lower bound for the amount of food waste in the U.S. (Hall et al. 2009). This analysis determined that prior estimates of national food waste were grossly underestimated; indicating that the national average caloric intake was much lower than previously estimated. As such, these results and those of Church imply that increased caloric intake or for that matter, increased sugar consumption, cannot solely account for the observed trends in national weight gain in the US.

The following is a summary of some of the research that has been published investigating whether obesity is related to physical inactivity and what effect increased physical activity has on obesity risk and management.

1. Banks et al. (2010) reported that: “Obesity increases with increasing screen-time, independent of purposeful physical activity.”

2. Goodpaster et al. (2010) found that: “Among patients with severe obesity, a lifestyle intervention involving diet combined with initial or delayed initiation of physical activity resulted in clinically significant weight loss and favourable changes in cardiometabolic risk factors.” In the group where physical activity was delayed, the addition of such physical activity promoted greater reductions in waist circumference and hepatic fat content.

3. Banks et al. (2011) showed that: “Domestic activities and sedentary behaviours are important in relation to obesity in Thailand, independent of exercise-related physical activity. In this setting, programs to prevent and treat obesity through increasing general physical activity need to consider overall energy expenditure and address a wide range of low-intensity high-volume activities in order to be effective.”

4. Villareal et al. (2011) demonstrated that: “…in obese older adults a combination of weight loss and exercise provides greater improvement in physical function than either intervention alone.”

5. McGuire & Ross (2012) reported that: “…light physical activity, incidental physical activity and sedentary behaviour were not associated with abdominal obesity amongst inactive men and women whereas moderate-to-vigourous physical activity predicted lower visceral adipose tissue.”

6. The study by Fan et al. (2013) was: “…to test if moderate-to-vigorous physical activity (MVPA) in less than the recommended ≥10-minute bouts related to weight outcomes.” Both higher-intensity short bouts and long bouts of physical activity related to lower BMI and risk of overweight/obesity whereas neither lower-intensity short bouts nor long bouts related to BMI or risk of overweight/obesity. They concluded that: “The current ≥10-minute MVPA bouts guideline was based on health benefits other than weight outcomes. Our findings showed that for weight gain prevention, accumulated higher-intensity PA bouts of <10 minutes are highly beneficial, supporting the public health promotion message that ‘every minute counts’.”

7. Cleland et al. (2014) found that: “High sitting and low activity increased obesity odds among adults. Irrespective of sitting, men with low step counts had increased odds of obesity. The findings highlight the importance of engaging in physical activity and limiting sitting.”

8. Jakicic et al. (2014) concluded that moderate-to-vigorous physical activity (MVPA > 10) of 200-300 min per week, coupled with increased amounts of low-intensity physical activity (LPA), are associated with improved long-term weight loss. Interventions should promote engagement in these amounts and types of physical activity.

9. Murabito et al. (2015) discovered that moderate-to-vigorous physical activity (MVPA) as measured by accelerometry was associated with less visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) and better fat quality as assessed by multi-detector computed tomography. With increasing MVPA, there was a concomitant decrease in VAT. Higher levels of MVPA were associated with higher SAT fat quality, even after adjustment for SAT volume. They concluded that:

“MVPA was associated with less VAT and SAT and better fat quality.”

10. Mekary et al (2015) reported that: “….over 12 years long-term weight training is associated with less waist circumference increase, whilst moderate-to-vigorous aerobic activity was associated with less body weight gain in healthy men.”

11. Hume et al. (2016) concluded that: “….counter to the energy surfeit model of obesity, results suggest that increasing energy expenditure may be more effective for reducing body fat than caloric restriction, which is currently the treatment of choice for obesity.”

12. Myers et al. (2016) suggests that there exists clear associations among objective measures of physical activity, sedentary behaviour, energy expenditure, adiposity and appetite control. They produced data that indicates strong links between physical inactivity and obesity with this relationship likely to be bidirectional.

13. Wu et al. (2017) tested 12-weeks of low- and high-intensity exercise training in Mexican-American and Korean premenopausal overweight/obese women. Results showed that such exercise reduced body mass index, body fat percentage, fat mass and visceral adipose tissue with concurrent increases in lean mass.

14. Quist et al. (2018) examined the effects of 6-months of active commuting and leisure-time exercise on fat loss in women and men who were overweight or obese. Clinically meaningful fat loss of over 4 kilograms was elicited. Vigorous intensity exercise was shown to be more effective in reducing body fat versus moderate intensity exercise.

15. Stoner et al. (2019) concluded that the findings of their meta-regression “lend support to the use of exercise prescription for promoting weight loss and improving health outcomes in adolescents with overweight/obesity.”

16. Zhang et al. (2020) found that 12-weeks of intense exercise (without concurrent nutritional intervention, i.e. ‘put on a diet’) significantly improved cardiometabolic parameters (i.e. fasting blood glucose) and decreased weight, total percent body fat, whole-body fat mass, android, gynoid, and trunk fat mass, abdominal subcutaneous fat and abdominal visceral fat. Reductions of over 15 cm² of abdominal visceral fat were achieved in just 3 months!

17. Berge et al. (2021) produced clinically significant weight loss in people with severe obesity despite the study having no specific focus on body weight reduction. The group that performed moderate‐intensity continuous training combined with high‐intensity interval training lost an average of 5 kilograms in 24-weeks.

Weight training, older adults and quality of life — Staying strong as we age is critical to health

What does this research tell us?

Quite a lot I would say. Of particular note is that this only represents a very small sample of the evidence that directly counters the claim that widespread societal levels of physical inactivity have little to do with burgeoning obesity rates. What is more, it crystallizes just how contentious Malhotra, Noakes & Phinney’s editorial was. Exclusively assigning blame for the obesity epidemic to the excessive intake of sugar is not supported, I believe, by the current evidence. The dramatic reductions in the sum total of all physical activity accumulated during the day appears to account for a substantial amount of the increased weight seen in recent decades.

Firstly, there is a substantial amount of research which demonstrates that sedentary behaviours, sitting time and low physical activity levels manifestly increase one’s risk of becoming overweight or obese. Secondly, moderate-to-vigourous physical activity compared to light physical activity has been shown to be associated with less visceral and subcutaneous adipose tissue, impacts positive effects on fat quality, is related to lower BMI, lowers risk of overweight/obesity, prevents weight gain following weight loss, promotes greater reductions in waist circumference and produces favourable changes in cardio-metabolic risk factors.

So to conclude, my Google Scholar search unveiled that there is a large body of evidence that demonstrates that there may be no myth to bust regarding obesity and physical inactivity or foundation to suggesting that physical activity plays no role toward promoting weight loss. Others have been critical of this line of thinking too, in particular Dr Steven Blair, so I would suggest that if you wanted to read further on this here would be a good place to start.

My next article will explore the evidence that exercise does not assist weight loss in all exercisers due to various compensatory mechanisms (see here). Until then, stay active, keep moving and don’t forget to include some resistance exercise in your week.

For local Townsville residents interested in FitGreyStrong’s Exercise Physiology services or exercise programs designed to improve health, physical function and quality of life 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.

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

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Strength, Weight/Fat loss, Nutrition, Mobility

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

January 5, 2020 seanwilso 2 Comments

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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:

High dairy protein diet (HP-D)
High non-dairy (soy) protein diet (HPeS)
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.

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

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Exercise Physiology, Strength, News/Media

The Australian Physical Activity Guidelines for “getting stronger”: Evidence-Based or Wishful Thinking?

September 24, 2019 seanwilso Leave a comment

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The development and publication of the “Australian Evidence-Based Physical Activity Recommendations for Adults (18-64 years)” by the Australian Government, The Department of Health (August 2012) promote the participation in “muscle strengthening activities” to:

• Manage blood pressure, blood sugar and blood cholesterol levels.

• Prevent and control heart disease and type 2 diabetes.

• Improve posture, mobility and balance.

• Reduce the risk of falls and injury.

• Maintain your ability to do everyday tasks.

However, let me inform you that there are components of these guidelines that have virtually no supporting scientific evidence. The advice that “I could do tasks around the house that involve lifting, carrying or digging” whilst facilitating energy expenditure and contributing to an active lifestyle are not well defined and are somewhat nebulous. For example, lifting a chair up, carrying a full bag of rubbish to the outside bin or doing some gardening will do very little to nothing to improve your muscle strength or power. Many of these are normal everyday activities that pose no significant challenge to our musculoskeletal system and hence will be unlikely to bring about full realisation of the benefits mentioned above. Perhaps you could contend that heavy digging that produces fatigue and requires constant breaks could be classified as “strength-like” training, but how many people (unless doing as a job) are out in the backyard doing regular heavy digging every week.

If you really want to improve your muscle strength and power, which has been shown to have so many benefits for older adults, and that I have outlined elsewhere (see here), you need to perform challenging resistive-type physical activities or exercise that involve “high effort”. You can utilise a number of different things to do this (e.g. traditional apparatus like barbells/dumbbells, kettlebells, machine weights or plain old bodyweight-based exercises or resistance bands or anything around the house that is challenging to to lift and move around…in fact pretty much anything if you know how) – but most importantly when you use any of these things the muscle work needs to be hard to very hard for you and/or high to very high in effort. If you meet such requisites you can be confident that what you are doing is resistance or strength training and will consequently help achieve the benefits mentioned previously.

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