Strength training is well known for creating stronger muscles and bones, and the benefits don't stop there. A review of studies published online Feb. 28, 2022, by the British Journal of Sports Medicine found that strength training is associated with a 10% to 17% lower risk of premature death from all causes, including heart disease, diabetes, and cancer. It's the latest of many studies to show a connection between strength training and good health.
What's the link?
Strength training triggers many body reactions that protect us against chronic disease. For example:
It helps reduce blood sugar. Muscles help the body store blood sugar, and strength training makes them better at it. That reduces the amount of sugar floating around in the bloodstream, which lowers the risk for diabetes and heart disease.
It lowers blood pressure. "Increased muscle mass means there are more blood vessels or pathways for blood to flow through. That takes pressure off the cardiovascular system," notes Dr. Deepak Bhatt, a cardiologist and editor in chief of the Harvard Heart Letter. High blood pressure is a major risk factor for heart disease.
It burns calories. Muscles burn calories 24 hours a day, and the more muscle you have, the more calories you use. This helps reduce fat and control weight. Obesity is a risk factor for heart disease, diabetes, and cancer.
It discourages chronic inflammation. "Strength training helps reduce certain fat cells, which put out signals to the body that increase inflammation," explains Dr. Edward Phillips, associate professor of physical medicine and rehabilitation at Harvard Medical School and Whole Health medical director at VA Boston Healthcare System. Chronic inflammation — the persistent activation of the immune system — is associated with heart disease, diabetes, cancer, and other chronic diseases.
How much strength training is necessary?
The 2022 review suggests that 30 to 60 minutes of weekly strength training leads to the highest amount of benefits. That's in line with the recommendation from the current Physical Activity Guidelines for Americans.
"If you work all major muscle groups, it should take about 30 minutes. So do 30 minutes, twice a week," Dr. Phillips says. "You can also just do a 10-minute session, six days per week—maybe after your daily walk."
But don't worry if you're not at that level yet. "One of the good things about exercise is that the benefits are incremental. It's not all or nothing. If you can't do twice a week, once a week is better than nothing," Dr. Phillips says.
The most important strengthening exercise you can do
It's essential to strengthen all of your muscles. But strengthening your abdominal, buttock, and leg muscles may be most important, since they make it possible for you to get up from a chair and sit down.
"Getting out of a chair becomes an athletic event as we get older. Doing 'sit-to-stands' will help you maintain your function and independence," says Dr. Edward Phillips, associate professor of physical medicine and rehabilitation at Harvard Medical School.
To do a sit-to-stand, sit in a fixed chair with your knees at a 90° angle. Stand up slowly without using your hands, then sit down. Repeat the process 10 times. To make it harder, do the movement with your arms folded. Eventually, hold free weights in each hand when you stand.
Exercise photos by Michael Carroll
How to start training
Get your doctor's okay before beginning a strength workout if you have problems with your bones, your balance, or your heart. Once you get the green light, you have many options for workouts.
Want to just test the waters? "Ordering some resistance bands for a few bucks and following a video online will ease you into it," Dr. Phillips says.
If you want to try something a little harder, take a beginner yoga class; follow an online video about free weights for beginners; or use the Harvard Special Health Report Strength and Power Training for Older Adults (/SPOA), which has workouts for beginner and intermediate levels.
You can also go to a local health club or gym and use weight machines or take a strength training class. "But unless someone has taught you how to strength train, it's best to get instruction before starting a routine like that. Work with either a physical therapist or a certified strength and conditioning specialist," Dr. Phillips advises.
No matter which approach you choose, make sure to strengthen all of your major muscle groups, including the arms, buttocks, and legs plus the core muscles in the torso.
The warm-up and cool-down
Two important aspects of a regular strength training routine are the warm-up and cool-down.
The warm-up gets blood flowing to the muscles, so they're pliable and don't tear when you put force on them. A warm-up could be a few minutes of dynamic stretching — marching in place and moving your arms around — or it could be your regular aerobic workout, such as your daily brisk walk.
After strength training, do a cool-down of static stretching (holding a stretch position for up to 60 seconds) to keep muscles long and supple. Stretch the calves, the front and back of the thighs, and muscles in the hips, shoulders, neck, and lower back.
Keep it up
Maintaining your strength training program will not only help ward off chronic disease, but also make you stronger. You'll find it's easier to get out of a chair and carry groceries, a laundry basket, or jugs of water. And it doesn't matter how old you are or if you've lost a lot of muscle from aging and inactivity. Your body will adapt, and you'll have stronger, more functional muscles.
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