How Much Exercise Do I Need to Lose 2 Pounds a Week?

The optimal way to drop excess pounds is to use a combination of exercise and lowered calorie intake. If you have decided that you will lose 2 lb. weekly through exercise alone, you will need to perform activities that will expend a total of 7,000 calories, as 1 lb. of body fat equals 3,500 calories. You'll have to exercise enough to burn around 1,000 calories daily if your calorie intake remains the same.

Cycling is an aerobic exercise. Aerobic means "with oxygen"; an aerobic exercise gets the heart pumping blood more quickly, which increases oxygenation and causes breathing to quicken. A 160-lb. person cycling at a pace of around 14 to 16 mph will burn approximately 770 calories per hour. To burn the necessary 1,000 calories daily without lowering your caloric intake, you'll need to cycle for around 75 minutes. If you ride at a leisurely pace -- less than 10 mph -- you'll need to cycle for at least three hours a day.

"Aerobics" is an exercise that involves moving energetically to music. Aerobics classes are held at gyms and local community halls, or you can buy a workout DVD to follow at home. During a low-impact aerobics session, the moves do not require that both feet leave the ground; one foot will have contact with the floor throughout the workout. However, a high-impact session involves hopping, jumping and running, and both feet will consistently lose contact with the floor, which requires more energy expenditure. During a 60-minute high-impact session, a 160-lb. person will burn around 500 calories. You'll need to perform two sessions lasting 60 minutes every day to lose 2 lb. a week if you don't plan to cut back on the number of calories you eat daily.

Swimming as an exercise has numerous benefits. It strengthens and tones all the muscles, and helps maintain a healthy heart and lungs. Vigorous swimming -- steady paced laps with heavy breathing and your heart rate elevated -- consumes around 710 calories per hour. To burn 1,000 calories with vigorous swimming, you'll need to swim for about 75 minutes a day. Swimming at a more moderate pace burns about 440 calories per hour. If you're not planning on cutting back on the number of calories you take in each day, you'll need about 16 one-hour sessions during one week to lose 2 lb.

Stair-step machines can be purchased in most sports shops and can easily be stored in a closet or under a bed when not in use. One hour of stair-stepping burns around 500 calories. If you perform four 30-minute sessions each day, you'll burn the required 1,000 calories to achieve 2 lb. of weight loss in a week without changing your eating habits.

Walking and running are aerobic exercises that can be used to help you lose 2 lb. weekly. The number of calories you burn will vary depending on your weight, age and the intensity level you do. If you weigh 154 lb., you burn 280 calories an hour walking 3.5 mph, according to the Centers for Disease Control and Prevention. When you run or jog an average of 5 mph, you burn 590 calories an hour. If your caloric intake remains the same, you'll need to jog or run for nearly two hours a day to lose 2 lb. a week.

Before beginning an exercise program to lose 2 lb. a week, talk with your doctor. Doing an activity such as running for two hours a day is strenuous -- you run the risk of injury if you're not conditioned to do that much exercise a day. Combine exercise with a sensible eating plan that reduces your caloric intake. If you cut out 500 calories a day and do an activity such as cycling for an hour that burns 500 calories, you'll reach your goal without physically overdoing it.