09 September, 2011
The Difference Between a Weight-Bearing and a Non Weight-Bearing Type of Exercise
Doing activities that move your body against gravity can help prevent osteoporosis. Approximately 50 percent of all women over the age of 50 will fracture their hip, wrist or vertebra, reports PubMed Health, but men are also vulnerable. As a person ages, bones become fragile and vulnerable to fracture as they lose their strength. Exercising is one way to reduce your risk of developing osteoporosis -- but not all exercise counts as weight bearing, the type you need to build bone density.
Like muscle and organs, bone is living tissue. Your body is constantly creating new bone but not always at an optimal rate. Exercise stresses the bones to stimulate a specific type of cells called osteoblasts to increase the bone's strength and density. A paper published in a 2009 issue of "Sports Medicine" notes that the best exercises to provide this stress and promote growth are those that require high force and generate impact. These are generally referred to as weight bearing.
Is My Exercise Weight Bearing?
Weight-bearing exercise moves you against gravity and generally has you on your feet. High-impact versions, which "Sports Medicine" noted were most effective, include dancing, high-impact aerobics, hiking, running, jumping rope, climbing stairs and sports such as tennis or basketball. Strength training is another form of weight-bearing exercise. Squats, lunges and deadlifts are examples of moves that have you working your body weight or additional weight against gravity, while pushups and dips work your upper body against gravity. Upper-body weight-bearing activity is important to maintain density in your wrists and forearms, which are areas particularly vulnerable to bone loss.
What About Swimming and Biking?
Non-weight-bearing activity keeps you off your feet. Swimming, for example, suspends you in water, which means you aren't stressing your bones. Similarly, biking doesn't require you to bear your body weight -- the bike does that for you. However, don't give up on swimming and biking, which offer tons of other health benefits -- simply alternate them with exercise that moves you against gravity. Some low-impact exercises, such as using an elliptical trainer, brisk walking and low-impact aerobics, do help build bone-density.
Functional, But Not Weight-Bearing
Exercises that promote balance and better daily function can help prevent falls, which cause fractures in people with osteoporosis, but they aren't necessarily weight bearing. The National Osteoporosis Foundation recommends Tai Chi and other balance exercises to strengthen your legs and hone balance. Though exercises to enhance posture are also valuable in preventing fractures along the spine, they do not count as weight bearing. Train to improve daily function, especially as you age, to prevent falls. Practicing simple movements such as getting up and out of a chair or stepping on and off a platform will help improve your balance for safety.
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