Everyone’s fitness level is different, and therefore exercise at a level that is comfortable for you. When you workout, you should be working out at an intensity level that is challenging, yet comfortable. This means that you should push yourself, challenge yourself, but not to the point of pain. If you experience pain or discomfort, then stop and modify your exercise to a level that is challenging yet comfortable.

For moderate intensity exercise, you should be exercising at 50-85% of your maximum heart rate. Training within this zone will, for most people, provides a challenging yet comfortable workout. your maximum heart rate is about 220 minus your age

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