"The benefits of an aerobic exercise program are physical and psychological," says Nancee Blum, social work specialist in psychiatry at the University of Iowa College of Medicine, who has taught aerobics classes to older adults.

People, young and old, who exercise regularly handle stress more effectively and don't get as fatigued. Aerobic exercise may also slow the aging process. It can help prevent heart disease and osteoporosis, and it helps fight obesity, making people stronger and more flexible. It lowers blood pressure, improves breathing, and those who exercise often have a higher self-image and self-esteem. It can also improve sleeping habits, appetites, and moods, she says.

"If you're an older adult, aerobic exercise won't make you an Olympic athlete, but it will help you to perform daily activities such as lifting grocery bags safely and climbing the stairs more effectively," Blum adds.

Before beginning an exercise program, consult your physician. There are several types of aerobic exercise, not just the bouncing and prancing around you often see on television. Walking, running, bicycling, and swimming are also considered aerobic exercise. To be effective, it should be performed for about 30 minutes at least three times each week, Blum says. "If you decide to walk, bicycle, or swim for exercise, it helps to find one or two friends to join you on a regular basis," she adds.

Whatever you choose, be sure it's something you enjoy or you'll find it difficult to keep at it. "Many people find it's easier to join an exercise class. If you join a class, try to join one with members in your own age group," Blum suggests. "Older adults often drop out of classes with both young and old members because of perceived competition."

The essential elements of aerobic exercise in older adults are the same as for young adults: safety and comfort, simplicity, variety, and enjoyment. A typical aerobics class runs about 45 minutes and includes warm-ups, aerobics, stretching, and a cool down, in that order. "Warming up gently stretches your muscles and gradually increases your heart and respiratory rates," Blum says. In addition to aerobic exercise, aim for two sessions per week of strength training.

Wear comfortable clothes that don't restrict movement and leg warmers or over-the-knee socks that can help prevent sore muscles in the lower leg, she adds. For an aerobics class, a properly fitted aerobics shoe is recommended. These shoes may also be worn for walking, but a shoe primarily designed for walking or running may hold the foot too rigidly for aerobic movements.

The old adage "No pain, no gain," is not true. If a movement causes pain, stop! Consult your physician if exercise results in chest pain, dizziness, cold sweats, extreme breathlessness, or very rapid heart rate that lasts longer than five to 10 minutes after stopping activity, Blum says.

Moderate exercise is better for everyone, no matter what age.