A previous PaleoHacks thread ties health and longevity to muscle mass, i.e. more muscle mass means a longer and healthier life. Brad Pilon and others have said that there is a genetic lean muscle mass "set point" that determines how much skeletal muscle your body wants to carry. However, you can "fool" your body into increasing muscle mass with resistance training. My question is how do I determine the optimum amount of time and effort to expend in building and maintaining muscle mass? From a vanity standpoint, as a 52 year-old ectomorph, I would like to be heavier. At what point do the health risks of stress and injury outweigh the health benefits of increased lean mass? Is it healthier to maintain your lean mass at your set-point as you get older, or to keep pushing it higher?
The answer is if you are an ectomorph you already carry the gene to live a long life (ACE II). If you are able to pack on muscle easily you do not carry this gene and instead have ACE DD.
"One other factor that likely separates the ‘ripped’, lean and strong ecto from that of the skinny-fact ecto is the angiotensin converting enzyme. Angiotensin converting enzyme (ACE) contributes to blood flow, blood pressure, vascularity, glycogen storage, and host of other things. In humans ACE _expression is dependent on what’s called insertion (I) or deletion (D) genes. Three phenotypes exist, I/I, I/D and D/D.
One specific ACE genotype, called II (insertion/insertion), is linked towards performance in aerobic events and has a cardioprotective effect. Those with the II ACE gene have less ACE, tend towards lower blood pressure, more Type I fiber, higher degree of vascularization, higher levels of interstitial glucose, less visceral fat accumulation and more subcutaneous fat accumulation. This is good if you want to be a marathon runner or live to be 100. Not so good if you wan to be a fast twitch dominant strength athlete or build a lot of muscle."
At what point do the health risks of stress and injury outweigh the health benefits of increased lean mass?
I would say that they very rarely do, so long as you're still at least vaguely functional (i.e. won't drop a weight on yourself, won't collapse if you raise your resting heart rate at all), which at 52 you should certainly be. Properly done, the health risks of stress and injury from weights ought to be pretty minimal. Conventional wisdom seems to be far too conservative about weight-lifting in general, without any particularly good grounds. Body By Science has a whole chapter about Weight-lifting for seniors (which you're not, in any case), but which essentially mandates that older people need the same sort of training as younger people. It also claims that this very slow, momentumless style of weight-lifting has less risk of injury than more rapid movements (although I would claim that the risk is very low in any case). I also seem to recall that an earlier chapter of the book discusses the risk of dropping-dead-from-a-heart-attack-because-of-doing-weights and finds that there's no reason to think that weight-lifting is unsafe (p264 if google books preview is revealing).
So I'm not sure why, from an optimal health standpoint, you'd not just train as intensely as possible in order to add lean mass. The qualification on this, is that I wouldn't recommend trying to add as much lean mass as possible tout court e.g. by eating constantly, eating excesss protein and trying to spike your insulin in diverse ways. That would doubtless be unhealthy, but I don't see anything unhealthy about training as hard as possible and letting your body add as much lean mass as it likes. Of course being an ectomorph (like me) that might not be very much mass at all, but you can at least get the health benefits of intense training regardless.
OTOH, adding a mere 10 lbs might put you into a shorter lifespan, according to the insurance actuarial tables. I'm just pointing out that nothing is certain, or even agreed upon.
There was a little dustup not too long ago out in the world in general, that fatter seniors lived longer than thinner ones. It turns out that many of the thinner ones were suffering from wasting diseases, such as cancer. So naturally they died sooner.
My question is how do I determine the optimum amount of time and effort to expend in building and maintaining muscle mass?
There, too, exists an endless amount of advice on what's optimal (periodization or whatever). But you probably just want something adequate. You can just do this: get dumbbells and enough weight to have 100 lbs on each, even much less to start. Do:
Eat more, and you'll likely grow. Not much time required. Maybe a few minutes of warmup before each workout of a few minutes. That's a minimum. That's better than nothing and better than overdoing it.
Dumbbells are safer, you can't get trapped under the weight.
After 40-50 yrs of age, you'll likely need longer recovery, so shorter workouts are better on that score. Being Paleo, you shouldn't have a problem getting enough protein.
There is endless variety and a lot of people want to say their way is best. They'll even argue. No need to argue.
Martin Berkhan claims the law of diminishing returns kicks in around the 4 or 5th year of weight training. http://www.leangains.com/2010/12/maximum-muscular-potential.html
"During the first six months of weight training, one might see a muscle gain of 1.5-2 lbs per month; that sweet newbie magic, where you gain muscle at a rapid rate. It's not uncommon to see that muscle gain accompanied by fat loss.
After six months and through the second year, you might see muscle gain of 1 lbs per month. You're able to increase weights linearly in the gym and everything is still pretty awesome.
Things slows down significantly in the third year, to the tune of about 0.5 lbs muscle gain per month.
In the 4-5th year of training, progress is slow. 1 lb of muscle every 4th month.
5-10th year, 1 lb per year."
So the only way to know your max potential is to train hard for 5 years and see where you are.