You can burn 500 calories on a treadmill in as little as 30 minutes or during the course of several hours, depending on how fast you run or walk. Your conditioning will determine how long it will take you to burn these calories, requiring you to walk at a slower pace to prevent fatigue, or letting you use several speeds and inclines to exercise.
A 160-pound person, walking at a moderate pace of 2 mph, will need almost three hours to burn 500 calories. Raise the level of your walking to 3.5 mph, and you'll burn those calories in less than two hours. Jogging at a pace of 5 mph burns 500 calories in about 50 minutes, while running at 8 mph lets you meet your calorie-burning goal in roughly 30 minutes.
To make sure you burn your calories before you become so tired you have to quit, vary the intensity of your workout during your walk. Start with a warmup of five minutes at 2 mph at a 0 incline setting to get blood flowing to your muscles and let your heart rate rise gradually. After you feel you are warmed up, raise your speed or raise the incline of your treadmill a few degrees to create a pace that challenges you, but won't fatigue you.
If the treadmill comes with a heart rate monitor, aim to keep your heart rate between 50 percent to 65 percent of your maximum heart rate. Experiment with one minute of brisk walking, light jogging or a more extreme incline followed by five minutes or more of relaxed walking.
Finish your workout by decreasing your speed by 0.5 mph and incline by one degree each minute until your heart rate is close to normal. Stretch after you get off the treadmill. Add dumbbell exercises or walking poles to your workout to increase your calorie burn.
Follow the same warmup procedure as for a beginner workout, raising your speed by 0.5 mph each minute until you reach the fastest pace you can continue without stopping. A low-impact, brisk walk will be 3 mph to 4 mph, depending on your height and stride length. Aim to keep your heart rate at 70 percent to 80 percent of your maximum heart rate. Add several sprints throughout your workout and increase the incline of your treadmill to create hills and valleys.
To burn the most calories in the least amount of time, run or sprint on a treadmill. When running during your workout, raise your pace to the fastest speed you can maintain for the duration of your workout. A running workout doesn't include sprints, which require you to recover at a walking pace after each sprint.
To sprint train, run almost as fast as you can for 30 to 90 seconds, slowing to a walk after to regain your breath and decrease your heart rate. Perform sprints at 80 percent to 90 percent of your maximum heart rate. Continue these sprints throughout your workout. Check with your physician before you attempt high-intensity sprint training.