Q: Will a treadmill or exercise bike help me lose weight faster? -Emily
A: The simple answer is a treadmill because you are going to burn more calories.
The complex answer is treadmills are much harder on your joints. Every time your foot hits the treadmill when you are running, it puts a tremendous amount of stress on your joints. The chance of injury goes way up with a treadmill. Bikes produce much less impact on your joints because your foot is constantly in contact with the pedal. To get the calorie burn up closer to treadmill levels, you can use an Airdyne Bike that requires you to pedal your arms and legs.
It also depends where you want to lose fat. There is some evidence that a treadmill will target the abdominal area better than a bike, and the bike will target the hips and thighs better than a treadmill.
If you really want to lose weight it isn’t about what machine you use, but about what you do when you are on the machine. If you are doing steady state cardio where you just stay at the same speed and resistance for your whole workout, you aren’t going to get the weight loss benefits you want as quickly as if you did interval training. Interval training requires changes in resistance and speed throughout your workout. Interval training not only burns more calories while you workout, but can continue to burn calories for up to 48 hours after your workout.