Should You Complete 20 - 45 Minutes of Cardio at Maximum Heart Rate for Weight Loss?

Getting 20 to 45 minutes of cardio will help you lose weight and contribute to your recommended weekly exercise for weight loss. But if you exercise at your maximum heart rate for this length of time you'll be doing more harm than good. If you want to lose weight, understand your safe heart rate range and know how much exercise you should be getting.

  1. Recommended Heart Rate

    • Working out at your maximum heart rate level for an extended period of time is painful and dangerous. According to the American Heart Association, you should work out at between 50 and 85 percent of your maximum heart rate. The website for the organization recommends starting out aiming for a heart rate of 50 percent of your maximum and gradually increasing. After exercising for about 6 months you should be able to work out at 85 percent of your maximum heart rate.

    Finding Your Range

    • Find your maximum heart rate by subtracting your age from 220. For example, if you're 30 years old then your maximum heart rate is 190 beats per minute. To find your safe range simply multiply your maximum heart rate by 50 percent and 85 percent to get your lower and upper ranges respectively. For instance, a 30-year-old with a maximum heart rate of 190 has a safe range of 95 to 162 beats per minute.

    Recommended Time Exercising

    • The American College of Sports Medicine recommends getting 150 to 250 minutes of moderate-intensity exercise per week for modest weight loss. According to the ACSM website, exceeding 250 minutes per week is likely to "provide clinically significant weight loss." You can divide your workouts up however you want so long as you get meet these numbers. For instance, if you workout six times a week for 45 minutes at a time, you'll get 270 minutes of weekly exercise.

    Considerations

    • Your target heart rate should be used as a guideline, not as an absolute range. If you struggle to talk when exercising then you're likely working too hard. Talk to your doctor before starting an exercise program to see if it's right for you. Your doctor may provide you with a different target heart rate, particularly if you have a heart condition.