Cycling and running are two exercise modalities commonly recommended for weight loss. Weight loss occurs when you burn more calories than you take in--and both allow you to burn significant calories without needing much skill or coordination. But when it comes down to it, the best exercise for weight loss is the one you are going to do.
The amount of calories you burn in either exercise depends on your fitness level, your current weight and the intensity at which you work. A 150 lb. person cycling moderately (about 13 mph) burns about 400 calories in just 40 minutes. Running burns more calories because it requires you to support your body weight. The average 40-minute run for a 150 lb. person will burn about 500 calories. Performing either activity on an incline amps up the calorie burn.
Both cardiovascular exercises strengthen your heart and improve your overall health. Both exercises build leg muscles and increase mobility at the hip joint. Running is a weight-bearing exercise and thus helps build bone density. Over time, both forms of exercise can help you maintain weight loss. Keep up an exercise program that burns at least 2,800 calories per week to keep pounds from creeping back on, as shown by participants in the Weight Loss Control Registry, a research group studying thousands who have successfully maintained weight loss.
Cycling might be better if you have significant weight to lose because it puts less pressure on your joints. Cycling is also more appropriate for those with knee or back issues. Cycling is also more appropriate for beginners. Beginning runners should walk or jog first to ease into running's intensity or risk developing shin splints. The more efficient you are at an exercise, the fewer calories you burn. If you are a runner looking to lose weight, consider swapping some runs for a bike ride to challenge your body in a new way and create a higher burn.
Although cycling and running both burn calories, they do not give you license to eat anything you want if you are trying to lose weight. Even if you are burning 500 calories in a session, it is easy to undermine that progress by with a "coffee" drink and a cookie. Be vigilant about eating healthfully with a focus on whole grains, lean proteins and fresh produce.
The best exercise to choose is the one you are most likely to stick with over time. Running slightly edges out cycling in terms of calorie burn. However, cycling offers more options for beginners, those with injuries or people who are significantly overweight. Yield the most results by including both in your regimen to keep challenging your body and prevent overuse of certain muscle groups.