A revisit of my screed on Aging

Awhile ago I posted a whiny poor-me screed after Coach Chad noted that no muscle growth occurs in the elderly. At the time I noted that studies of 70-year-olds as athletes were a bit thin and that given the difference between active and inactive elderly that more study might be needed to validate assumptions about age and plasticity. Today, after doing VO2Max intervals, I came upon this video from the ECSS, the European Congress for Sports Science.

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The Older Muscle: Ageing or Disuse?
Harridge, S.
King`s College London

The prime role of muscle is to act as a biological machine - to produce force and generate power. … As we get older there is an observable reduction in many of these functions. This is primarily related to a loss of tissue mass, which when passing a given threshold is referred to as “sarcopenia.”… However, the extent to which sarcopenia and its attendant side effects can be attributed to an inherent biological ageing process are far from clear.

……For example, limb immobilisation, bed rest or exposure to microgravity (space flight) all result in muscle loss and weakness- irrespective of age. The effects of many years of a sedentary lifestyle thus seriously confound our understanding of the properties of a muscle we might expect for a given chronological age.

To what extent are these phenomena attributable to the biological ageing process and what can be done to ameliorate these deleterious effects? … Recent experiments on highly active older people have thrown some light on answering these questions. These studies have shown that despite ageing, muscle mass, function and quality can all be well maintained. These data suggest that we need to rethink our perceptions on the interactions between ageing, exercise and physiological function.

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What I get from this presentation: Disuse in the generally sedentary elderly population contaminates the evaluation of aging and athletic ability.

Biological aging it seems is not as deleterious as disability from disuse. Power per kilo of muscle mass declines from age, but even more from disuse. Disuse has the same effects at all ages; the change from youth to age is the ability to rebound. Loss of strength occurs whether there is loss of muscle mass or not—old people lose power. But, old athletes lose far less power and have higher VO2Max, and can maintain a level of fitness equivalent to people many years their juniors.

This may indicate that individuals who exercise effectively will lose power but their muscles may not lose the ability to maintain or possibly increase in mass over time if motor neurons are still in place and the muscle stem cells are still active. A result of that might be the ability to incrase power by increasing mass, but at an attenuated level compared to a young person, i.e. old guy gains a watt for a given change in activity while a younger person will gain more from the same effort…

There is also evidence that plasticity may be greater than previously understood. The assumption for elderly is that muscle mass cannot increase, but an interesting study quoted in this presentation showed that muscle that had been removed from a 17-day-dead cadaver could still grow new cells from muscle stem cells. What to make of that?

I’m going to keep spinning and let the scientists figure it out. Don’t stick a fork in me. I’m not done and I’m in the middle of doing intervals. And thank you TR and Coach Chad for this platform and these workouts. You guys are making my life so much better.

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