By Bonnie Jenkins, Advanced Natural Medicine
Have you ever noticed that people have thinner arms and legs as they get older? As we age it becomes harder to keep our muscles healthy. They get smaller, which decreases strength and increases the likelihood of falling. New research shows why this happens—and what you can do about it.
As you age, you lose muscle size and strength much faster than you lose endurance or coordination. Researchers at the University of Nottingham in England recently discovered a surprising cause of this age-related muscle loss—insulin. It turns out that insulin, the hormone often associated with diabetes that regulates carbohydrate and fat metabolism, also slows down muscle breakdown. Insulin drives amino acids into muscles to help them recover from exercise and maintain their size.
The Curse of the 40 Plus
This system works beautifully in the under 40 set. But once you hit middle age, insulin fails to efficiently shut down this breakdown. As a result, folks around 50 years of age start to lose muscle. In fact, our muscles begin to waste at approximately 0.5 to one percent a year. That means that an 80 year old may only have 70 percent of the muscle a 50 year old has. Since the strength of skeletal muscle is proportional to muscle size, such wasting makes it harder to carry out daily activities requiring strength, such as climbing stairs, and leads to a loss of independence and an increased risk of falls and fractures.
But here’s the good news: Exercising just three times per week can reverse this muscle wasting. Unfortunately, simply taking a leisurely stroll around the block won’t do the trick. To truly preserve your muscles, you need to up the intensity of your workout. And that means resistance training.
Resistance exercise doesn't mean resistance to exercise! It’s any exercise that causes the muscles to contract against an external resistance with the expectation of increases in strength, tone, mass and/or endurance. The external resistance can be dumbbells, rubber exercise tubing, your own body weight, bricks, bottles of water or any other object that causes the muscles to contract. But don’t just jump into resistance training. That’s a sure-fire way to hurt yourself. Instead, start slowly, using fairly light weights—two to five pounds is ideal.
If possible, try to work with a personal trainer, even if you just hire one for a session or two. It's difficult to learn how to correctly lift weights from a book or even a video. Learning how to lift weights properly will give you the confidence you need to lift on your own and get stronger and stronger.
Beginners can start with one set per exercise. You can do more if you have time, but research shows that one set for beginners is enough to yield significant gains in strength. Remember that muscles grow during downtime, not when you train, so allow a day or two between workouts so that the muscles can recover and grow. On your “off” days, try doing 30 minutes of cardio to get your heart rate up. Walking, water aerobics or, if you’re fairly fit, a Zumba or other type of dance class are all good choices.
You Are What You Eat
What you eat after your workout can also encourage muscle growth. Eating a high carbohydrate-high protein meal or snack within half an hour after finishing a workout raises insulin levels, increases amino acid absorption into muscle and hastens recovery. The carbohydrates cause a high rise in blood sugar that causes the pancreas to release insulin. Insulin drives the amino acids in the meal into muscle cells to hasten healing from intense workouts. Muscles are extraordinarily sensitive to insulin during exercise and for up to a half hour after finishing exercise, so the fastest way to recover is to eat protein- and carbohydrate-rich foods during the last part of your workout or within half an hour after you finish.
Supplements Fuel Muscle Growth
Preliminary research shows that chromium enhances insulin signaling and insulin-mediated glucose uptake. As a result, chromium not only builds muscle tissue, it also burns fat. In a study published in Medicine and Science in Sports and Exercise, researchers from the University of Texas at Austin examined the effect of chromium on body fat in a group of 43 overweight women. Following nine weeks of exercise training and chromium supplementation, fat loss was significantly greater in the chromium group compared to the women using no supplement. Most people experience this benefit by combining regular resistance training with chromium (as chromium polynicotinate) daily. Just be aware that chromium supplementation may enhance the effects of some diabetes drugs like insulin and may lead to hypoglycemia. If you are diabetic, work with your doctor before trying chromium.
The benefits of resistance training are numerous. It helps maintain bone density, benefits your cardiovascular system, helps keep blood sure levels in check and boosts balance and coordination. Plus, muscle burns more calories at rest than fat, so you might even lose some weight. It’s a win-win proposition. So what are you waiting for? Start pumping iron today for a vibrant and independent tomorrow!
Burd NA, et al. Exercise training and protein metabolism: influences of contraction, protein intake, and sex-based differences. Journal of Applied Physiology. 2009; 106: 1692-1701.
Raue U, et al. Improvements in whole muscle and myocellular function are limited with high-intensity resistance training in octogenarian women. Journal of Applied Physiology. 2009;106:1611-1617.
Volek JS, et al. Effects of chromium supplementation on glycogen synthesis after high-intensity exercise. Medicine and Science in Sports and Exercise. 2006;38:2102-2109.
Wilkes EA, et al. Blunting of insulin inhibition of proteolysis in legs of older subjects may contribute to age-related sarcopenia. American Journal of Clinical Nutrition. first published on Sep 9, 2009 as doi: doi:10.3945/ajcn.2009.27543.