I’ve been a competitive athlete all my life and my body has experienced MORE than its fair share of tissue damage: concussions, torn muscles, broken bones. Getting back in shape after an injury was never easy, but I always managed to bounce back…until I reached my 40’s and was, well, slowed down somewhat by my diagnosis of severe osteoporosis. Regaining competitive-level strength after that setback was quite an ordeal. I attributed the uphill battle to the long period of inactivity while I healed myself. I was half right. I forgot about age. Aging also has a lot to do with the difficulties of trying to regain muscle mass and strength after a period of inactivity.
This past winter I came down with a nasty persistent cough, courtesy of the flu. Absolutely zero exercise for almost three months (plus a few months before that when I was just lazy) resulted in a completely deconditioned and flabby sorry-state of a body. Then my son called me a few weeks after the Boston Marathon bombing. “Dad, we have to run Boston next year. It’s just something we HAVE to do…it’s REALLY important! You need to find a marathon to run so you can qualify.” “And quick, the dead-line for qualifying is in September!”
I knew what my son was saying. It would be such an important demonstration of solidarity by the running community to return to Boston even stronger. No terrorists were going to stop us…not us runners…not all of the passionate spectators that cheer us on…not us tough-as-nails Bostonians/New Englanders/Americans… NO WAY!
A few clicks on the computer told me I would need to run at least a 3:40 marathon and probably a 3:30 to guarantee a qualifying spot. “That’s do-able” I said to myself with some doubt. “Now, find a marathon that still has entry spots left in it…” Planning and training to run a marathon should be a year-long venture. Six months is pushing it. Oh, did I mention I’m approaching age 60? The ONLY marathon I could find after my search, the Around the Lake Marathon in Wakefield, MA, was in just 12 weeks (well, 11+…but who’s counting). Hmmm…. “Better get started…”
In a study published in The Journal of Physiology, Suetta et al. investigated what types of cellular mechanisms may be involved in muscle mass recovery after a period of immobilization and how these may change as we age. They found that muscle re-growth after a period of inactivity is diminished as we age due to a failure of quiescent immature muscle cells to activate into mature muscle. Instead of developing into contracting muscle cells in response to re-instating an exercise program, these satellite precursor cells remain dormant. They just don’t wake up. Even after 4 weeks of resistive exercise, the study found that regrowth of muscle mass in elderly individuals was diminished compared to younger males.
(“Great…just what I wanted to hear…”)
In addition to reduced muscle cell development, aging is also associated with elevated levels of a protein called myostatin. This protein is a signaling molecule secreted by muscle cells and is important for limiting muscle growth. Myostatin ensures that you don’t inadvertently end up looking like Arnold Schwarzenegger. Now I certainly don’t want to look like Arnold but I do need some muscle strength (in addition to aerobic capacity) to run a marathon. The problem is that as we age, myostatin levels increase and this makes it increasingly difficult to gain or even maintain muscle mass and strength. When muscle cells waste away it is called sarcopenia, a wasting condition often seen in the sick or elderly. Even higher levels of myostatin are found in these people. Unfortunately, sarcopenia (and excessively elevated levels of myostatin) is also commonly seen in patients with osteoporosis. Muscle and bone actually “talk” to each other by way of signaling molecules such as myostatin. When an individual has osteoporosis, this “cross-talk” between muscle and bone can create an even greater barrier to re-gaining muscle mass once it is lost.
I devote an entire chapter in my book, The Whole-Body Approach to Osteoporosis, to explaining how muscle wasting correlates with osteoporosis and vice versa, and what to do about it. Reducing inflammation, creating a more-neutral body pH, limiting oxidative stress, ensuring adequate protein intake, and adding a few key supplements can help maintain an anabolic physiology and stave off muscle and bone loss. Exercise itself is of utmost importance. In fact, exercise helps not only increase IGF-1 production (the most powerful anabolic agent naturally produced in the body) but it also increases GASP-1, a myostatin binding protein that lowers myostatin levels.
Yes, these past 5 weeks of training seem slower to stimulate muscle tone than I remember. With only 7 weeks remaining to race day I’m certainly beginning to wonder about reaching that 3:30 cut-off time to qualify for Boston. I guess illness and injury are unavoidable but there is no doubt that sticking to a regular exercise program (when possible) is your best bet for retaining muscle mass and strength. For those of you who are exercising, stick with it! And for those of you who have let it slide…the sooner you can re-boot your program, the better. (Stay tuned for an update on the marathon (July 26th) and my run for Boston.)
Suetta, C., 2013. Aging is associated with diminished muscle re-growth and myogenic precursor cell expansion in the early recovery phase after immobility-induced atrophy in human skeletal muscle. The Journal of Physiology. June 3 [Published online].