Exercise Safety

The health benefits of being active far outweigh any risks. But that doesn’t mean there are no risks. For an elite athlete, a weekend warrior, or anyone just starting out on a fitness plan, physical activity does increase the risk of injury. (1) Don’t let that stop you from becoming more active, though: Moderate intensity activity is generally very safe for most people, even people who have not previously been active. And you can lower your injury risk by taking a few simple precautions.  

What kind of injuries can result from physical activity? Muscle, joint, and bone problems are the most common. (2) In hot weather or during long, intense workouts, dehydration can be a concern. In very rare cases, vigorous physical activity may lead to a heart attack or sudden death. Keep in mind, though, that active people have an overall lower risk of serious or fatal heart problems than inactive people. If you are sedentary, starting with activities that require a light-to-moderate effort, such as walking, and increasing your activity gradually can be a safe way to get moving.

The more fit you are, the lower your risk of getting injured. (1) The best way to get fit is to make physical activity a routine part of your day and week—and to be safe about how you do it.

The Physical Activity Guidelines for Americans 2008 offers these tips for staying safe while being active: (1)

1. Pick activities that match your fitness level.

Some activities are riskier than others, especially if you’re not in shape. The safest route? Choose activities that are moderate in intensity; have less of an impact on your muscles, bones, and joints (for example, walking instead of running); and don’t involve planned contact or collisions with other people or objects (for example, tennis or golf instead of volleyball or hockey). Several popular activities have low injury rates:

  • Walking for exercise
  • Gardening and yard work
  • Bicycling or riding an exercise bike
  • Dancing
  • Swimming

2. Increase activity gradually.

Most of us need to become more active. As we increase our activity, though, the larger the increase over our usual activity level, the greater the chance of injury. Gradually upping your physical activity over time can help lower your injury risk, regardless of how active you are now.  If you’re currently sedentary and looking to add more activity to your day, it’s especially important to “start low and go slow.” There’s no hard and fast rule as to what constitutes a gradual increase. (2) Trainers typically recommend increasing the length and number of activity sessions before increasing intensity. If you usually spend 20 minutes on the stationary bike twice a week, for example, increase to 22 minutes, then 24 minutes. Slowly add more sessions during the week, until you are meeting the Physical Activity Guidelines for Americans recommendations. (1) Read more about exercise guidelines for children, adults, and older adults.

3. Protect yourself.

A few common-sense precautions can help you stay safe:

  • Choose the right equipment: If you’re cycling, wear a bike helmet. If you’re going out for a walk, pull on a well-fitting pair of sneakers instead of a pair of flip flops.
  • Find a safe place to work out: Seek out streets that have sidewalks or bicycle lanes. Play basketball on well-maintained courts.
  • Pay attention to the weather: In the middle of a heat wave, exercise in the morning when it’s cooler out, exercise indoors, or hit the swimming pool instead of the tennis court.

4.Talk to your doctor if you have a chronic condition or if you are pregnant.

Physical activity can help people manage diabetes, heart disease, arthritis, and other chronic conditions, as long as the activities they choose match their fitness level and abilities. If you have one of these conditions or another chronic condition, your doctor can help you come up with an activity plan that’s safe for you. Pregnant women should also talk to their health care providers about the safest activity options during pregnancy and after having a baby.


1. U.S. Dept. of Health and Human Services. 2008 Physical Activity Guidelines for Americans. 2008. Accessed December 2, 2010.

2. Physical Activity Guidelines Advisory Committee. Physical Activity Guidelines Advisory Committee Report. 2008 Washington, D.C., 2008. Accessed December 2, 2010.

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