Tag Archives: exercise

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

12 Reasons Why Older Adults Need To Do Resistance Training Exercise: Part 1

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What are they:

  1. Increases longevity and improves quality of life
  2. Helps manage hypertension and decreases heart disease
  3. Enhances sleep quality and quantity
  4. Prevents/treats type 2 diabetes & decreases inflammation
  5. Prevents cognitive decline & neurodegenerative disease
  6. Improves mental health 
  7. Enhances skeletal health
  8. Maintains or increases lean body mass (muscle)
  9. Increases strength, power, speed and physical function
  10. Reduces body fat and help maintain body fat loss
  11. Improves endurance performance 
  12. Reduces injury risk

Resistance or weight training is a critical component of training programs of most elite athletes irrespective of the sport. The benefits of resistance training – to increase maximal muscle strength and neuromuscular power – has long been recognised by most strength and conditioning experts, coaches and sport scientists as key to sporting performance. Logic would dictate therefore that if elite athletes are doing concurrent training to improve sport specific performance, masters athletes may also reap huge benefits too. There is now compelling evidence to suggest that resistance training can potentially augment athleticism of masters athletes well beyond that achieved by confining training to sports specific training. Furthermore, these significant benefits are not just limited to sprint, speed or power orientated sports but endurance performance may also be enhanced.

However, before I address the athletic performance benefits of resistance training for older athletes and functional enhancement such exercise has in older non-athletes (these will be outlined in part 2), I want to discuss the significant and sometimes life-changing health benefits that have been well documented in research conducted over the last 20 years. There is a great deal of data now to support the use of resistance training to help treat and manage a number of chronic diseases that become more prevalent as we get older. The following outlines 6 key reasons why resistance training exercise should be included in all programs of older athletes and exercise programs of older non-athletes.

strength training for over 50
Resistance Training Reduces The Risk Of Death

Reduce the risk of death. Evidence continues to accumulate to show that skeletal muscle strength is strongly predictive of longevity. Maximum muscle force in men aged 20-80 is independently and inversely associated with all-cause mortality. Over the age of 60 years, all cause and cancer-associated mortality is twice as likely in individuals with low compared to high skeletal muscle strength. Older adults over 15 years who reported twice/weekly strength training had 46% lower odds of all-cause mortality than those who did not. Resistance training when performed regularly is one of the best methods to increase skeletal muscle strength (see links 1, 2, 3, 4). A recent assessment of the research that has been conducted in older adults showed that resistance training substantially improved health-related quality of life. In other words, resistance training and getting stronger has a direct impact on our perception of how meaningful, manageable and comprehensible life is, and as such, significantly greater promotion of this type of activity is warranted (see here).

strength training for over 50
Resistance Training And Cardiovascular Health

Helps manage hypertension and decrease heart disease. High blood pressure can still affect masters athletes and resistance training when performed in conjunction with aerobic or endurance training has been shown to have a positive effect and reduce blood pressure. However, data to support resistance training as a stand alone practice is mixed with some studies suggesting improvement in systolic and diastolic blood pressure versus other research that has shown such exercise can increase arterial stiffness. Evidence tends to point to concurrent exercise (resistance training combined with aerobic exercise) as being the most effective for reducing the risk of heart disease (see links 1, 2, 3, 4).

strength training for over 50
Resistance Training Facilitates Better Sleep

Improves sleep quality and quantity. Problems with sleep are common with advancing years and occur in over half of adults age 65 and older. It has been estimated that insomnia affects about a third of the older population. The evidence to date suggests that poor sleep hygiene directly impacts and worsens many aspects of health including such things as mental health, obesity, heart disease, cognition, memory, executive function, metabolic disturbance and falls to name just a few.

Overall quality of life is thus dramatically reduced. Other factors associated with ageing, such as disease, changes in environment, or concurrent age-related processes also may contribute to problems of sleep. Sleep disturbance and long sleep duration, but not short sleep duration, have been shown to be associated with increases in markers of systemic inflammation. Research has shown that both sleep quality and quantity is improved with increased levels of exercise. Resistance training alone appears to positively impact sleep quality but more data is required to confirm that sleep quantity is equally improved (see links 1, 2, 3).

strength training for over 50
Diabetes Rates Continue To Increase

Prevent/treat type 2 diabetes & decrease inflammation. Type 2 diabetes mellitus (T2DM) is one of the fastest growing non-communicable diseases worldwide and occurs much more frequently in those that are overweight and obese. However, impaired blood glucose metabolism, one of the hallmarks of T2DM, is an increasingly common problem in those that are not overweight and have relatively normal BMI.  A poor and overindulgent diet – high in things like sugar, trans-fats, processed foods, junk foods and that are low in fish (omega-3 fatty acids), vegetables, fruit, fibre and high quality protein – combined with long-term sedentarism has been postulated as playing a leading causative role. Such a combination causes the development of chronic positive energy balance whereby excess energy disposal and adipose storage triggers a significant oxidative pro-inflammatory response referred to as metabolic inflammation.

In obesity, expanding adipose tissue attracts immune cells creating an inflammatory environment within this fatty acid storage organ. Skeletal muscle is the predominant site of insulin-mediated glucose uptake and insulin resistance is considered the primary defect that is evident years before the development of T2DM. Resistance training has consistently been shown to improve the ability of the skeletal muscles to take up and metabolise blood glucose (sugar) and is therefore an important strategy in managing T2DM. Finally, there is now scientific data to show that disorders that arise and are linked to inflammation (e.g. Insulin resistance, obesity, cardiovascular disease, diabetes, cancer, chronic kidney disease, osteoarthritis, Alzheimer’s disease and many more), can be improved or mitigated with resistance training and exercise (see links 1, 2, 3, 4, 5).

strength training for over 50 female
Resistance Training Enhances Brain Health

Prevent cognitive decline & neurodegenerative disease Recent research has shown that long-term resistance training in older women promotes executive function, memory, reduced cortical white matter atrophy and increased peak muscle power. Such findings are very exciting as they suggest that exercise and resistance training can modify brain neuroplasticity and help improve brain function. The current thinking is that resistance and physical exercise represents a promising nonpharmaceutical intervention to prevent age-related cognitive decline and neurodegenerative diseases such as dementia and Alzheimers. There is some evidence that the mechanisms behind these alterations may be related to increased levels of Brain-derived neurotrophic factor (BDNF) and IGF-1. BDNF-induced neuroplasticity is speculated to be facilitated by physical exercise but conclusive evidence supporting this mechanism of action has not yet been established (see links 1, 2, 3, 4).

strength training for over 50 female
Mental Health Is Significantly Improved with Resistance Training

Improved mental health. There is substantial evidence to demonstrate that resistance training and exercise more generally has a very dramatic and potent effect on improving mental health and treating those that suffer from mental health disorders. For example, research has shown that high-intensity resistance training is more effective than low-intensity resistance training or standard care by a GP in the treatment of depression in older patients. Resistance exercise has also be shown to reduce anxiety, slow the progression of white matter lesions in older women, improve symptomatology and disease severity in severe mental illness and essentially improve overall quality of life and general mental health (see links 1, 2, 3).

To finish up I cannot emphasise enough just how important resistance training exercise is for all older adults including masters athletes. The reasons mentioned above are only some of the many that support resistance training exercise as an essential ingredient of a healthy lifestyle and confirm current recommendations for people to partake in a minimum of 2 resistance training sessions per week.

To read part 2 of “12 reasons why older adults need to do resistance training exercise” which discusses the performance-enhancing benefits for older athletes and the incredible functional improvements that can be achieved in older non-athletes, see here.

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.

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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Exercise Physiology, Weight/Fat loss, Nutrition

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

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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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Exercise Physiology, Strength, Mobility, Exercises

Why we need to look beyond just traditional strength training exercises for older adults

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Exercise professionals involved with older adults pay a great deal of attention to the lower limb prime movers¹ and exercises² which will enhance the strength and power of these important muscles, and so we should. There are all sorts of ingenious ways to increase the strength, function and aesthetics of these muscles, just take a quick look at Instagram and you’ll see what I mean. The hip abductors are now recognised also, in both research and practice, as playing a pivotal role in hip and knee function influencing gait and postural stability, particularly in the medio-lateral plane. But what about the hip adductors? Are they a forgotten piece of the puzzle? Rarely do we see much attention paid to exercising these muscles of older adults in any sort of meaningful way³. This is interesting in and of itself and a curiosity, but the inference is that the adductor muscle group is not viewed as important enough to dedicate any time to specifically develop its neuromuscular capacity irrespective of some recent research that certainly suggests otherwise. There is now enough evidence to support the adductors being treated as a distinct target for improved muscle strength and power production. In fact, FGS would contend that this muscle group deserves the same degree of focus as the quads, GMax, hamstrings and hip abductors in any resistance training program for older adults given the following:

  • Age-related hip adductor strength loss appears to be more pronounced compared to the knee extensors (Daun & Kibele, 2019).

  • Postural instability with ageing is especially problematic in the medio-lateral plane (Mille et al 2013).
  • Neuromuscular rate of activation of adductors (AM) is significantly lower in older versus younger adults for both forceful static muscular contractions (IMVC) and dynamic recovery following lateral balance perturbations (Inacio et al 2019).

  • Power-based resistance training of the hip adductors (and hip abductors) has been shown to elicit improvements in maximal neuromuscular performance and enhanced medio-lateral balance recovery. Traditional (slower tempo) performed resistance training did not result in significant improvements in isolated or balance-related neuromuscular or biomechanical performance (Inacio et al 2018).

Based on the abovementioned research, FitGreyStrong’s recommendation is to ensure that weight-bearing exercises that load and challenge the adductor muscle group (frontal plane) be included in resistance training programs of older adults. Moreover, it should be acknowledged that open kinetic chain seated machines may not provide the appropriate neuromuscular challenge to bring about improvements in medio-lateral balance and function (Daun & Kibele, 2019; Inacio et al 2018) however, further research is required4.
Footnotes:
1 Quads, GMax and hamstrings
2 Squats, deadlifts, glute bridges, hip thrusts, leg curls, sit-to-stands, step-ups etc
3 The same could be said for the hip flexors where age-related muscle mass and strength losses occur disproportionately compared to other major muscle groups and this obviously impairs physical function and gait potentially increasing the risk for falls.
4 Thanks to Rhys Manchester for pointing out some inconsistencies with these concluding remarks.

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

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Exercise Physiology, Strength, Nutrition, Tidbits

Can Vitamin D supplementation augment strength gains in older adults doing resistance training?

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In a recent meta-analysis (see here), vitamin D was found to provide an additive benefit for older adults partaking in resistance training (RT). In other words, when compared to older adults taking a placebo, significantly greater gains in muscle strength were achieved in those supplemented with vitamin D. However, upon closer analysis several issues become obvious that are difficult to reconcile. The following discusses some of these issues inherent in the findings of this paper (see below).

The group 1 analysis of 3 trials finds vit D supplementation augments muscle strength of the lower limbs, SMD=0.98; see fig 2 below. (Please click on any image to open and make larger for viewing).

…but what is with the scale used for the x-axis; it seems all wrong…..all the green squares sit nicely on zero……. and where is my forest plot with 95% CI bars and my black triangle to show overall SMD?

As a crude comparison & to put this in context, Chilibeck et al (2017) found SMD=0.25 for the effect of creatine supplementation on lower body strength during RT in older adults. Perhaps the most effective supplement available? Could vit D really be that much better? 

The authors acknowledge serious inconsistency with substantial heterogeneity (see table 5) for this outcome measure and even suggest that maybe: “….these studies were unsuitable for comparison”, but conclude nonetheless that there is: “tentative support for the additive effects of RT and vit D supplementation for the improvement of muscle strength in older adults”, including those replete in Vit D.

The Uusi-Rasi et al (2015) trial was weighted heavily (75%) and rightly so being the most well designed, largest & longest RCT to date. In fact SMD of this trial in the group 1 analysis = 1.16. This is very impressive and clinically relevant if accurate and valid. Uusi-Rasi et al (2015) in contrast states: “Irrespective of vit D, exercise increased muscle strength. The predicted mean increase in lower limb extension strength was almost 15% in both exercised groups and differed significantly from the placebo without exercise group.”

“Another unexpected finding was that exercisers treated with vit D supplementation showed consistently smaller benefits than exercisers receiving placebo……our results indicate that vit D may not improve neuromuscular function, at least when vit D intake is sufficient.” The largest and longest RCT to date found no additional – and perhaps even attenuated – benefit of vit D supplementation in replete resistance-training older adults, which is at complete odds to the meta-analysis.

The Agergaard et al (2015) trial showed no additional benefit of vit D on muscle strength in older adults (vit D replete). Sample size for older adults was very small also and weighted acccordingly in the meta.

….and Bunout et al (2006) found that combined calcium/vit D supplementation was no more effective than calcium-only supplementation in older adults undergoing RT but – and this is a critical point of difference to the other 2 studies.

– all participants were arguably vit D insufficient; to be included participants had to be 16 ng/ml (40 nmol/L) or less for serum 25(OH)D. An important point that was missed by the authors of the meta-analysis (see further below).

These 3 studies included in the group 1 analysis of muscle strength of the lower limbs were identified as “all participants took part in RT and the intervention arm was supplemented with vit D (describing the additive effect of vit D supplementation when combined with RT)”

However, Bunout et al (2006) did not include a RT group that received a ‘true’ placebo. Both exercising groups in this trial received supplementation of some sort.

….one group was supplemented with vit D & calcium (intervention), the other exercising group were supplemented with calcium-only (control). “……vit D was given along with calcium in this trial, since a low calcium intake can limit the effects of the vitamin.

To isolate the effect of the vitamin, controls for supplementation received calcium also.” However results showed there were no statistically significant differences between these groups in baseline to final percentage change for right and left quadriceps strength, and right and left hand grip strength. In fact, the RT plus calcium-only group achieved better mean numerical responses in strength (non-significant) when compared to the RT plus vit D/calcium group (see table 2)……..so is it somewhat unusual that such a large SMD was found in the meta favouring the group that received vit D?

The authors state in the meta discussion that: “Interestingly, although the studies included within group 1 did not specify serum 25(OH)D levels as inclusion/exclusion critieria, baseline and postintervention serum 25(OH)D were within the ‘sufficient’ range (>30 nmol/L).”

Now there are 2 issues with this statement. Firstly, it is false that all studies included in group 1 did not specify serum 25(OH)D levels as inclusion/exclusion criteria. Bunout et al (2006) in fact did just that and specified a cut-off point for inclusion.

Subjects were screened and included only if their serum 25(OH)D levels were 16 ng/ml (40 nmol/L) or less. Secondly, mean baseline serum 25(OH)D of the vit D supplemented group in Bunout et al (2006) was 12.4 ng/ml (30 nmol/L) and many experts would propose that serum 25(OH)D of around 30 nmol/L in older adults is insufficient. It is also worth noting that Vit D status for participants of each of the 3 studies varied considerable and could possibly confound the meta.

After reviewing the 3 trials very carefully (used in the group 1 analysis of Antonia and Greig 2017), the finding that vit D supplementation significantly augments muscular strength of older adults doing RT, including those replete for vit D (SMD=0.98), is perplexing.

It is plausible and there is some evidence that vit D supplementation may augment strength of exercising older adults that have insuffient or deficient levels of vit D [serum 25(OH)D <50 nmol/L & <25 nmol/L] but such data is as yet not forthcoming in older adults performing RT

After reviewing Antoniak & Greig (2017) in which vit D supplementation significantly enhances strength in older adults doing RT, I cannot but view the findings as an artefact possibly generated by the unresolvable and substantial heterogeneity that was detected in the analysis.

The conclusion of tentative support for the ergogenity of vit D in older RT adults, irrespective of serum 25(OH)D status, is therefore premature and unsubstantiated.

For local Townsville residents interested in FitGreyStrong’s Exercise Physiology services or exercise programs designed to improve muscular strength, physical function (how you move around during the day) and quality of life or programs 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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