Obesity is a medical condition in which an individual's body weight exceeds healthy limits and is defined as a body mass index (BMI) of 30 or greater. Physical activity plays an important role in treating obesity; however, special considerations must be understood. The American College of Sports Medicine (ACSM) warns that obese people are at an increased risk for orthopedic injury. For this reason, obese people should follow a workout program that consists of non-weight-bearing or low-impact exercises.

Walking

Walking at a slow pace can ease you into more intense fitness activities. Slow walking helps burn calories and may lower the risk of arthritis and injuries to the joints compared with brisk walking by obese adults, according to research published in 2007 in "Medicine and Science in Sports and Exercise." Walking also provides several health benefits, including improved cholesterol and blood pressure levels, improved mood and better weight management. You can walk inside on a treadmill or outside around your neighborhood or at your favorite park.

Water Activities

Swimming is a challenging activity that anyone can perform. For people who are overweight, swimming is perhaps the best way to exercise because it alleviates stress on the leg joints, according to an excerpt from Gail Kislevitz' book "It's Never Too Late" published on U.S. Masters Swimming. Swimming works virtually every muscle in the body and provides a substantial cardiovascular workout.

Water aerobics is another way to work out in water. The water helps to cushion stiff joints and brittle bones of obese and elderly people that may otherwise be injured during impact activities on land. Moving in the water also adds resistance, which strengthens and tones muscles.

Elliptical Machine

An elliptical machine offers similar cardiovascular benefits as jogging but is much easier on the joints, which is ideal if you are obese and already experience joint problems. When exercising on an elliptical trainer, your feet never leave the pedals, so the impact your body endures is minimal. The elliptical also allows you to train your upper body simultaneously with your lower body, which allows you to burn more calories in a shorter amount of time. Keep in mind that only high-end, commercial-grade elliptical machines have the capacity to safely accommodate individuals weighing more than 250 lbs.

Stationary Bike

By offering bodily support during exercise, stationary bikes are a low-impact and safe mode of exercise for obese people. Rather than having to bolster your body weight and concentrate on exercising, you can take a seat on a sturdy bike and focus on pedaling. Indoor cycling gives you a cardiovascular workout without stressing weight-bearing joints. Most bikes also offer a resistance setting, which allows you to constantly challenge yourself and build strength in your legs. A quality bike can safely support a 300-lb. person, and most bikes are comfortable for any body size.

Low-Impact Aerobics

Low-impact aerobics are those movements involving large muscle groups used in continuous rhythmic activity in which at least one foot contacts the floor at all times. This form of exercise works well for overweight people, seniors and pregnant women by offering stability and joint and bone protection throughout the workout. Aerobic sessions involve controlled upper and lower-body movements that work to elevate your heart rate as well as increase your overall strength. Low-impact aerobics offer all of the health benefits of a regular aerobics class so you won't be missing out on anything except pain.