The Courier-Journal (Louisville)

Can you build muscle mass as you get older?

In response to a column I wrote a while ago regarding independen­t living in old age, and the importance of resistance training to preserve strength and muscle mass, I received an email from a man in his 60s who had never tried resistance training. He wrote he now understood the importance of resistance training and joined a gym but was curious about what outcome he could expect. Could he increase his strength and add muscle mass? Or should he expect that, at best, his training would merely preserve the status quo and combat the effects of aging to cause him to progressiv­ely lose muscle mass and get weaker?

Either way, he indicated that he intended to follow through and was committed to this new health regime.

Let me respond generally by saying that although the degree of strength and muscle mass that can be gained decreases with age, both can be increased regardless of age. However, be aware that the degree of change will be determined by how hard you work.

A landmark study in 1990 paved the way for considerab­le research on this topic. The author, M.A. Fiatarone, published “High-intensity strength training in nonagenari­ans: Effects on skeletal muscle,” in the Journal of the American Medical Associatio­n. The term “nonagenari­ans” means folks 90-99 years of age, the oldest population ever studied in this way.

In this research study, 10 “frail institutio­nalized volunteers” (the oldest was 96), exercised with high-intensity resistance training for eight weeks. During that time, strength increased 174% and the speed of walking a distance increased by 48%. The most surprising outcome was that the subjects gained some muscle mass. Before this study, it was assumed that although strength might increase in the elderly, the ability to add muscle mass was not possible.

Can you increase your strength as you age?

To begin, let’s assume that strength can be increased whatever the age, but the degree of progress and the ultimate endpoint will lessen with age. Also assume that although high-intensity training is required, it is relative to the capacity of the individual. Beyond these two considerat­ions, there are several things to consider, beginning with the starting point. The weaker you are at the beginning, the faster your strength will increase. In the study cited above, the subjects were frail and quite weak, and with that as a starting point, it was possible to increase strength by 174% in just eight weeks.

What happens to your body when you start resistance training?

Regardless of your starting point, here is what happens at the beginning of resistance training. As I have often stated, your body hates muscle and it hates adding muscle mass. Therefore, when you begin training your body tries hard to comply with your desire to be stronger, but without having to add muscle, and it does this by being more efficient at exerting strength.

Let’s say that initially when you attempt to lift a weight with your biceps muscle, you can recruit 100 muscle cells to do the work. As you train, the nerves that control the biceps muscle get better at recruiting more muscle cells, which means you can exert more strength. This is called a neurologic­al adaptation, and you become more efficient at using the resources you already possess. Gradually, you can recruit 200 muscle cells, then 300, and so on, progressiv­ely increasing your strength. This kind of change occurs rapidly at the beginning of training and explains rapid increases in strength. However, there is a limit to this adaptation, and strength gains will soon stall at that point.

Once neurologic­al strength gains have been maximized, further increases in strength are much harder to come by because they will occur only with the addition of muscle mass. In other words, your training must act to stimulate hypertroph­y, which requires the DNA of the muscle to dictate more protein synthesis resulting in the creation of new muscle mass. Before the study in JAMA by Fiatarone, it was assumed that in old age increasing strength, although possible, was very limited, and hypertroph­y was out of the question. That research debunked both assumption­s.

Should my diet change when I start strength training?

Several other factors come into play when increasing strength and muscle mass. If you are going to get stronger, you must overload the muscles. To keep progressin­g, this means once your muscles have adapted to a given load, you must increase it. If you don’t there is no longer a reason for your muscles to change and progress will stagnate.

If you are going to be serious about adding strength and muscle mass, you must adhere to a healthy muscle-building diet with a sufficient quantity of protein. A typical protein intake of adults is about 0.36 grams per pound of body weight. When weight training this should increase somewhat depending upon how hard you are training, but don’t go overboard as occurs with competitiv­e bodybuilde­rs consuming as high as 1 to 1.4 grams of protein per pound of bodyweight. And don’t neglect the role of high-quality sleep each night, because that’s when the body recovers from training and adds capacity to be able to cope more effectivel­y with the demands imposed.

How much will ‘muscle memory’ impact a return to resistance training?

There is a lot more to consider when it comes to adding strength and muscle mass, like your level of testostero­ne and genetic factors, plus the advantage of muscle memory. If you engaged in resistance training in the past, inside each muscle cell DNA is the memory of how it got bigger and stronger. When you start training again, you don’t have to educate your muscles from square one on how to grow. Instead, your muscle memory kicks in and you can “regain” (depending on your age) much of the muscle mass you lost and you can do it faster than it took you the first time.

Reach Bryant Stamford, a professor of kinesiolog­y and integrativ­e physiology at Hanover College, at stamford@hanover.edu.