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Strength training: Get stronger, leaner, healthier

校友推荐 By Mayo Clinic staff December 26, 2011

Strength training is an important part of an overall fitness program. Here's what strength training can do for you — and how to get started.

You know exercise is good for you. Ideally, you're looking for ways to incorporate physical activity into your daily routine. If your aerobic workouts aren't balanced by a proper dose of strength training, though, you're missing out on a key component of overall health and fitness. Despite its reputation as a "guy" or "jock" thing, strength training is important for everyone. With a regular strength training program, you can reduce your body fat, increase your lean muscle mass and burn calories more efficiently.

Use it or lose it

Muscle mass naturally diminishes with age. "If you don't do anything to replace the lean muscle you lose, you'll increase the percentage of fat in your body," says Edward Laskowski, M.D., a physical medicine and rehabilitation specialist at Mayo Clinic, Rochester, Minn., and co-director of the Mayo Clinic Sports Medicine Center. "But strength training can help you preserve and enhance your muscle mass — at any age."

Strength training also helps you:

Develop strong bones. By stressing your bones, strength training increases bone density and reduces the risk of osteoporosis.
 Control your weight. As you gain muscle, your body gains a bigger "engine" to burn calories more efficiently — which can result in weight loss. The more toned your muscles, the easier it is to control your weight.
 Reduce your risk of injury. Building muscle helps protect your joints from injury. It also contributes to better balance, which can help you maintain independence as you age.
 Boost your stamina. As you get stronger, you won't fatigue as easily.
 Manage chronic conditions. Strength training can reduce the signs and symptoms of many chronic conditions, including arthritis, back pain, depression, diabetes, obesity and osteoporosis.
 Sharpen your focus. Some research suggests that regular strength training helps improve attention for older adults.

Consider the options:

Strength training can be done at home or in the gym. Consider the options:

Body weight. You can do many exercises with little or no equipment. Try push-ups, pull-ups, abdominal crunches and leg squats.

Resistance tubing. Resistance tubing is inexpensive, lightweight tubing that provides resistance when stretched. You can choose from many types of resistance tubes in nearly any sporting goods store.

Free weights. Barbells and dumbbells are classic strength training tools.

Weight machines. Most fitness centers offer various resistance machines. You can also invest in weight machines for use at home.

Getting started

When you have your doctor's OK to begin a strength training program, start slowly. Warm up with five to 10 minutes of stretching or gentle aerobic activity, such as brisk walking. Then choose a weight or resistance level heavy enough to tire your muscles after about 12 repetitions.

"On the 12th repetition, you should be just barely able to finish the motion," Dr. Laskowski says. "When you're using the proper weight or amount of resistance, you can build and tone muscle just as efficiently with a single set of 12 repetitions as you can with more sets of the same exercise."

To give your muscles time to recover, rest one full day between exercising each specific muscle group. When you can easily do more than 15 repetitions of a certain exercise, gradually increase the weight or resistance. Remember to stop if you feel pain. Although mild muscle soreness is normal, sharp pain and sore or swollen joints are signs that you've overdone it.

When to expect results

You don't need to spend hours a day lifting weights to benefit from strength training. Two to three strength training sessions a week lasting just 20 to 30 minutes are sufficient for most people. You may enjoy noticeable improvements in your strength and stamina in just a few weeks. With regular strength training, you'll continue to increase your strength — even if you're not in shape when you begin.
Strength training can do wonders for your physical and emotional well-being. Make it part of your quest for better health

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