More On “Use It Or Lose It”- And How to “Get It Back”
There was a great article in Alex Hutchinson’s “sweat science” blog about maintaining sprint speed as we age. It was mostly geared towards running, but applies to other activities like hiking, biking, swimming, etc. , as well. This is one of the physical qualities that declines fastest in older adults. Even those who are sedentary still walk around quite a bit, but our activities of daily living no longer require much higher intensity work. A major exception is going up stairs, which is why I’m a big believer in using stairs, not escalators or elevators, as much as possible.
We’ve discussed this before. But the new article explains how we also start to lose “motor units“, which are bundles of muscle fibers wired together so they are fired by the same neuron. These will actually get disconnected with age if we don’t use them. Use it or lose it indeed. But a new study investigated how this happens, how to prevent it, and how to “get it back” after we’ve “lost it”.
Our bodies try to compensate if we then try to work hard at an older age. The remaining motor units will look around for “orphan” muscle fibers to recruit. So we end up with fewer, larger, motor units instead of more smaller ones. This makes our movements less smooth, but is better than losing the muscle strength entirely. But this happens to a much lower extent for master’s athletes who stay active all their lives. By 65 they’ve still got almost all their motor units. It does decline by 85, so they’ve only got about 60% left, but sedentary people the same age only have about 40% left.
Ok, so we can prevent losing it if we use it. “Everybody knows that”. But what to do get it back? The authors in the new study give several suggestions. One is to work on the “high end intensity” of your activity. Alex points out that for running, where this would mean working on sprinting, the concern about this for older athletes is fear of injury. That is where I believe other activities with less impact like biking or stair climbing are useful because they are less injury prone.
I still managed to injure myself stair climbing last summer but that was because I jumped into doing stair sprints suddenly when we had bad air due to wildfires. So I’d add this suggestion: if you’re starting to work on high intensity, or switching to a new activity, do so gradually.
The next suggestion is resistance training. The study authors emphasized the importance of working on your muscle mass, strength, and power. This requires different types of work, like low reps/heavy resistance for strength, and more explosive training with lower resistance for power. I’ve described basics of resistance training in a previous post and how to do it time-efficiently if it’s not your favorite. The single set exercises with heavy resistance in that post are good ways to cover strength and mass. This may not be an optimal program for bodybuilding, but will do nicely for older adults (like me). The double ski poling exercise in that post is a good example of a power exercise. You can also work on power doing your favorite aerobic activity, for example hiking faster uphill or biking up a hill in higher gears.
Finally, they recommend consuming adequate protein. I discussed the protein needs for older adults being a bit higher here, especially if you’re trying to gain back muscle mass.
If you’ve “lost it”, don’t despair. There are studies of nursing home residents in their 90s gaining back a significant amount of strength through resistance training, which makes a huge difference in quality of life.