Do-it-Yourself Home Gym

Exercise balls are great for calisthenics and stretches, as well as warm-up and cool-down routines.

You don't need a home gym to exercise at home. Here are four inexpensive, easy-to-store alternatives that, together, enhance all the elements of fitness: muscle strength, flexibility and cardiovascular endurance. All are sold in sporting-goods stores.

Getting on the Bandwagon

Elastic exercise bands are a perfect option for beginning strength training. They've been used by physical therapists for years. Cheap (usually about $3 a band,) portable and versatile, these long, wide bands provide the resistance you need to work your muscles. They often come with illustrated booklets. The bands' colors reflect the level of resistance. You can strengthen and tone virtually all your major muscles -- and work them from a variety of angles, depending on what you use as an anchor for the elastic band.

Rowing. Sitting on the floor with your legs extended, loop band under arches of feet and hold one end in each hand. Start with arms extended forward. Keeping your back straight and shoulders down, pull your elbows back slowly, contracting shoulder blades. Hold for two seconds; release slowly. Repeat.

Tips: Start with easy resistance and gradually increase the difficulty. If you're stretching the band too much, switch to a harder resistance. Keep the band at its normal width so that it doesn't cut into your hands, feet or ankles. After stretching the band, release it slowly, but do not let it go slack. Wrap the band securely around your hand or foot so it won't slip. When an exercise calls for anchoring one end of the band, choose an object that won't move, such as a pole or heavy piece of furniture.

Having a BIG Ball

The big vinyl therapy ball -- also called a physio-, Swiss, or gym ball -- has been used for 30 years in Switzerland. Now these balls are turning up in gyms and physical-therapy offices across the U.S. Filled with air and relatively soft, unlike medicine balls, they cushion you as you stretch. They come in different sizes, for people of different heights. For instance, a 65-centimeter (about 24-inch) ball is recommended for those between 5'8" and 6'. Inflated with a simple pump, they start at about $20.

You can do calisthenics (strengtheners) and stretches on the ball, as well as warm-up and cool-down routines. Ball workouts require the use of multiple muscle groups. For instance, by simply sitting and bouncing on the ball, you work your hamstrings, quadriceps, abdominals and back muscles. Add arm movements, and you also get an upper-body workout. The main benefits are improved coordination, balance and posture.

Stretch for hip flexor muscles. Kneeling, put your stomach on the ball. Keeping one knee forward and bent at a 90 degree angle, put forearms on the ball. Extend the other leg backward, with the knee on the floor. Hold and feel the stretch in the front of your hip. Your front knee should be over the foot. Then lift the back knee, straighten the back leg and stretch again. Switch legs.

Tips: When you sit on the ball, as you would a chair, your thighs should be parallel to the ground. Don't wear pins or anything that might puncture the ball. Make sure you have enough room so that if you lose your balance, you won't fall onto a piece of furniture. If you are older and/or have poor balance, start off with a "spotter" -- someone who will stand alongside you and make sure you don't fall off the ball.

Taking Your Medicine Ball

For a different kind of ball workout, try medicine balls. Leather versions used to be popular among trainers and athletes in the 1930s. Today these weighted balls, dubbed "plyoballs" or "body balls," are usually made of polyurethane and/or vinyl.

What you do with a medicine ball is called plyometric exercise. This involves stretching a muscle (as when you squat before you jump to shoot a basket) and then contracting it suddenly or "explosively" as you jump. You can hold the ball above your chest to make your sit-up routine more strenuous. Or substitute it for hand weights while doing aerobic dance. Or play toss or keep-away with one or two partners. Plyometrics can build muscle strength, thus increasing power for specific sports.

Twist. Sitting with your back at a 45 angle to the floor, move the ball from side to side, twisting your upper body.

Tips: Start with a small, lightweight ball -- about 18 inches in diameter and weighing five to nine pounds. Balls over 16 pounds should be used only in professional training. Vary your workout to avoid overuse injuries or soreness. For advanced or intense plyometric exercises, consult a trainer.

Learning the ropes

Jumping rope is great exercise for adults as well as kids. All you need is a rope and good shoes -- plus a little instruction at first and then some practice.

As aerobic exercise became a byword in the 1980s, rope jumping gained new popularity -- for good reason. As a way to build cardiovascular endurance, jumping rope can be as strenuous as jogging, but is lower in impact, since you should jump only a little off the ground. It helps improve coordination, speed and agility. If you engage in a sport (such as tennis, basketball, or skiing) that requires bursts of speed and power, jumping rope can be particularly beneficial. It works muscles in the legs, shoulders, chest and forearms. And it burns lots of calories.

Check the rope length. Stand on the center and pull the handles up your sides: the ends of the handles should come just up to your armpits.

Wear shoes with good support; aerobics shoes or cross-trainers (not running shoes) are best. Make sure the rope handles fit comfortably in your hands. It's best to jump on the kind of springy wood floor found at a gym or health club, but a lawn or a mat works well, too. Carpets are fine, but a thick one may throw off your timing. Concrete is too hard and increases the risk of injury, but if your shoes are good enough you should be able to jump anywhere.

If you are just beginning to jump, start at about 70 turns a minute, which allows you to double-hop each jump. Keeping your elbows near the sides of your hips, turn the rope with your wrists and forearms -- don't turn from the shoulders. To minimize stress on your legs, jump just high enough for the rope to pass under your feet -- only an inch or two off the ground. Land softly on the balls of your feet and let your heels help absorb the impact. Land with your knees slightly bent. Keep your posture erect, shoulders back and abdomen tucked in. Slow down if you get winded or too tired. Jumping rope can elevate your heart rate very quickly.