Do you want to build muscle? You run, walk, and ride your bike to keep your heart and lungs in excellent condition. You stretch your muscles and do yoga to stay limber and flexible. But are you also doing regular strengthening exercises?
Strengthening or resistance exercises are vital to keep the muscles that support your back, abdomen, knees, chest, shoulders, neck, and wrist strong and less susceptible to injuries. Strong muscles mean greater endurance and energy, a faster metabolism (which burns more calories), and better posture.
If you're a teen who's overweight, you're certainly not alone. In the United States, the number of people who are overweight is dramatically increasing. In fact, the percentage of teens who are overweight has more than tripled since 1980. In 2004, almost one in five teens was overweight.
Strengthening exercises work muscles as they move against resistance. This resistance can come from workout machines, free weights or barbells, elastic bands, water, stairs, hills, cans of vegetables from the pantry -- even your own body weight as you do a pushup.
For example, walking on a treadmill (which is aerobic exercise) becomes strengthening as you increase the incline of the treadmill.
Benefits of Strengthening Exercises
Just as aerobic exercise keeps your heart in peak condition, regular strengthening exercises help keep your other muscles strong and healthy.
For example, your lower back and abdominal muscles stabilize the spine, allow proper spinal movement, and help with posture. Strengthening hip and leg muscles is also important, so you can safely lift objects from the floor using your leg muscles rather than those in your back (if you're lifting using your back muscles, be prepared for back pain in young adulthood).
Strengthening exercises also increase muscle mass. Muscle mass is the metabolically active tissue or tissue that burns calories. So the more muscle mass you have, the more calories you burn all day.
Resistance exercises also burn calories during the actual workout. One study found that resistance training could burn as much as 200-300 calories an hour -- about the number of calories in a piece of thick-crust cheese pizza.
Further, strengthening exercises help lower blood pressure and reduce cholesterol levels. This is important in preventing heart disease as an adult. These exercises also decrease the chance of osteoporosis and bone fractures by encouraging the deposit of calcium in the long bones and spine.
Should I Use Weight Machines or Free Weights?
Weight machines and free weights each have advantages and disadvantages. Machines at a fitness center may be good for beginners. Machines help ensure that you perform the movement with proper form. At a gym, you also have the advantage of an instructor to help you use the machine correctly.
Machines also isolate specific muscle groups, allowing you to strengthen your biceps, triceps, leg muscles, abdominal muscles, the chest, shoulders, back, or other area. Further, free weights carry a higher risk for injury. It's not likely, for example, that machine weights will fall on you.
On the other hand, free weights can be more convenient. You can use them in your home, outside, or at the school gym. Although free weights require strong hands and wrists, they allow you to do more types of exercises and give you a greater range of motion than machines do.
Because the risk of injury is higher with free weights, however, it's best to exercise with someone when using heavy weights. This way, you can "spot" for each other and keep the weight bar from dropping and injuring you. Also, free weights require that you be properly trained in lifting techniques to prevent injuries, particularly to your back and shoulders.