http://www.marksdailyapple.com/organ-reserve-muscle-mass-aging/

http://blog.modernpaleo.com/2010/03/muscle-mass-for-health-and-longevity.html

Really interesting article here (full text available for free)

We conclude that healthy older adults show evidence of mitochondrial impairment and muscle weakness, but that this can be partially reversed at the phenotypic level, and substantially reversed at the transcriptome level, following six months of resistance exercise training.

Maybe not only about muscle mass and aging, but about strength training and aging.

If I'm not mistaken, I think Dr. McGuff also refers to this article in his book 'Body by Science'.

I keep on using this while talking with people about aging and muscle mass:

If you age, you don't lose muscle mass, it is the opposite: if you lose muscle mass, you age.

This must be a quote from somebody, but I don't remember (If somebody does, please let me know)

[edit] seems like the above quote is from Art De Vany. I should have known...

Great links, jm054. It is simple to think of your muscle mass, your bone structure and your fat tissue as reserves (as well as their other roles). At some point, your body dips into these reserves to support life, to survive famine, to protect other key structures or processes.

Certainly entering later life with robust bone and muscle will help a person to avoid injury, and to have a reserve to draw upon if the need arises. Some heavy lifting and proper paleo livin' is a worthwhile past time to build muscle and bone. I worry for my cardio-obsessed rail-thin contemporaries as we all march on in years.

If you age, you don't lose muscle mass, it is the opposite: if you lose muscle mass, you age.

This must be a quote from somebody, but I don't remember (If somebody does, please let me know)

I think Arthur Devany is the one who invented the phrase