By Dr. Jeremy Girmann
“Can I still make muscular gains at 60 years old?”
Among many there floats the idea that we exit this world much the same as we entered – rather pathetic and weak. How’s that for optimism?
We can fill our heads with examples of people we’ve known, individuals that would seem to satisfy this apparent truth. There are, however, those who stand in sharp contrast to the notion of an inevitable decline into frailty and dependency.
What is it about these individuals, the ones who emanate strength and live robust lives decade after decade, which sets them apart from the rest?
We are all aging – today, tomorrow, and everyday to come (learning anything yet?…). While it is true that certain physiologic phenomena occur with advancing age that necessitates change in lifestyle, or perhaps more meaningfully, change in perspective, we ought not to allow this to construct a ceiling over our efforts to optimize our health and performance.
Dr. Walter Bortz, a geriatrician and author of the book Next Medicine suggests that we do not stop moving because we age, but rather we age because we stop moving.
The truth of this idea seems to readily reveal itself in the world of medicine as it applies to nearly every body system. Use it or lose it. Motion promotes motion. It’s inertia…
The trajectories of health traveled by lifelong athletes greatly oppose those of dedicated couch potatoes. While readers of this publication are unlikely to require convincing of these correlations, we will consider to what degree our physical strength and muscular size are limited by the number of candles on our cake.
It is true that as we age, we tend to experience a gradual decline in strength and lean body mass. Researchers initially attempted to capture these physiologic changes with the term “sarcopenia” which is of Greek derivation meaning “poverty of flesh”. We do know that after the age of 30, inactive individuals generally experience an average 1% loss of muscle mass per year and that this change in muscle mass tends to result in impaired strength and function. For many researchers it followed that preservation of lean muscle tissue would attenuate strength loss. It was subsequently demonstrated, however, that the changes in muscle mass do not explain the entirety of strength loss. This concept is likely to be well appreciated by readers of this column when we consider the strength changes of people who have been newly introduced to weight training. Within the first few months of training, individuals can experience significant increases in strength without a proportional increase in muscle mass. This is largely due to adaptations of the neurologic system. In a similar way, strength losses that occur with age are not only attributable to a decrease in muscle mass. For this reason, Dr. Brian Clark of the Ohio Musculoskeletal and Neurological Institute coined the term “dynapenia”, meaning “poverty of strength”.
The importance of the distinction between sarcopenia and dynapenia resides in the consideration of an approach to mitigate these phenomena.
A 1% loss of lean muscle mass after the age of 30 seems to be a bit of a defeating proposition. This is, however, a statistical average and I can say with certainty that readers of the Performance Press are far from average. There are plenty of individuals who have more than prevented muscle loss as they age and managed to regularly add lean muscle tissue from a combination of dietary, exercise, and lifestyle interventions.
The Society for Sarcopenia, Cachexia, and Wasting Disease (there is a professional society for nearly everything) convened an expert panel to develop recommendations for prevention and management of muscle and strength loss. It was decided that a combination of exercise (both resistance and aerobic), adequate protein and caloric intake, creatine supplementation, and vitamin D replacement seem to offer the surest ways maintain muscle and strength.
Let’s consider these factors a bit further…
Muscles are made of protein – this we know. Active individuals require a higher protein intake since they have greater protein turnover in their muscles. There are several reasons why aging individuals might be deficient in protein or perhaps less sensitive to its effects:
In a study published in the Journal of Nutrition in 2003, it was determined that 32–41% of women and 22–38% of men older than 50 years consume less than the recommended dietary allowance (RDA) for protein, and virtually no older adult consumed the highest acceptable macronutrient distribution range for protein.
Simply, you’ll be hard-pressed to build muscle on a diet of tea and toast.
In The American Journal of Clinical Nutrition in 1997, a process involving leucine kinetics identified that “the extraction of dietary amino acids by the splanchnic bed is altered in advanced age, which can translate into lower peripheral amino acid concentrations”. In other words, there was a decrease in the absorption of protein into the blood vessels within the gut in older individuals.
In 2011 it was shown in the Proceedings of The Nutrition Society Journal that aged muscle possesses a reduced ability to up-regulate protein synthesis in response to anabolic stimuli, such as protein intake and physical exercise. However, provided that the stimuli are sufficient, muscles from older individuals retain the capacity of mounting a robust anabolic response following the ingestion of protein-rich meals (particularly meals high in leucine).
With consideration of the above factors, insuring adequate protein intake is central to efforts directed at maintaining and building muscle as we age.
A study in The American Journal of Clinical Nutrition in 2008 demonstrated that among 70–79 year-olds over a 3-year period, individuals in the highest quintile of protein consumption lost nearly 40% less appendicular lean mass than did those in the lowest quintile.
‘Nuff said about protein? Now let’s consider creatine.
Creatine is a compound, present in all muscle tissue, which primarily acts as a phosphate donor to regenerate ATP – the chief energy currency of our cells. In other words, creatine helps to regenerate energy in a working muscle when energy stores become transiently depleted. In addition, creatine has been shown to cause an increase the transcription of genes involved in muscle protein synthesis, cell repair and survival pathways, satellite cell activation, and muscular levels of insulin-like growth factor 1 (IGF-1).
In advanced age, a decrease in intramuscular creatine levels has been demonstrated. As reported in the Journals of Gerontology in 2003, however, it was shown that administration of creatine monohydrate to older adults engaged in strength training programs increased intramuscular creatine concentration, augmented muscle mass, and improved muscular strength. Similarly, in 2008 it was reported in Medicine & Science in Sports & Exercise that when intramuscular creatine levels are maintained with creatine supplementation, the breakdown of muscle tissue is reduced.
How about vitamin D?
In 2010 it was shown in the Journal of Clinical Endocrinology that in individuals of advanced age, serum levels of vitamin D were strong, independent predictors of changes in muscle mass and strength.
While the mechanisms underlying the actions of vitamin D are many and complex, vitamin D supplementation has been shown to improve muscular function and positively impact muscle fiber composition and morphology.
In addition to the above, omega-3 fatty acids and antioxidants have been shown to positively influence muscle tissue maintenance and muscular strength.
After discussing the utility of several possible dietary and nutritional supplement interventions, I would be remiss to mention nothing of exercise. Perhaps more intuitive than the rest, exercise does encourage preservation of muscle mass and strength. Perhaps surprisingly, however, it has been shown that even 20 to 30 minutes of resistance and aerobic exercise 3 times a week is capable of slowing muscle loss and preventing sarcopenia. If an increase in muscle mass is the goal, exercise intensity would no doubt need to be emphasized. Often I find that individuals associate intense exercise with extremely heavy workloads. While we know that use of heavy weight effectively encourages muscle hypertrophy, it has also been demonstrated that exercises performed with lighter loads, if performed to fatigue, also promote robust increases in hypertrophy and strength. This is good news for those who may need to lighten the loads as issues with joint health are encountered.
With enthusiastic commitment and observance of the factors listed above, adding power in the pecs and bulk to the biceps later in life is far from being out of the question.