Many people injure themselves because they are so obsessed with trying to get to 30 minutes of continuous exercise that they won’t stop exercising when they feel pain. If you are out of shape, you should start exercising each session only until your muscles feel heavy or sore and then stop for the day. Eventually, you should be able to work up to a full 30 minutes.

If you can’t exercise for 30 minutes straight in a sport, try to get at least 30 minutes of full exercise or vigorous activity during the day. According to the American College of Sports Medicine, you don’t need to exercise vigorously for long periods of time to reap substantial health benefits. If you exercise for 30 seconds, rest for 30 seconds, and alternate exercise and rest, you should be able to exercise for much longer without injuring yourself.

If you get tired at the beginning of a sport, you can exercise in several sports, stopping at each one when you feel the slightest discomfort. For example, go to your aerobic dance class and stop when you feel a little tired, even if you have to stop after two minutes. Rest and then ride an exercise bike until your legs start to feel heavy, perhaps for three minutes. Later in the day, take a walk until you feel tired. Aim for a combined total time of 30 minutes of exercise per day, three to five days a week. You can count any physical activity that keeps you constantly moving, such as walking, climbing stairs, or working in the garden.