SATURDAY, DAY 6
LIFESTYLE AND PREVENTIVE MEDICINE
Weight-bearing, or load-bearing, exercise is exercise you do on your feet that requires you to work against gravity. It is the best type of exercise for building and maintaining bone mass, which is important for preventing bone fractures and the form of bone loss known as osteoporosis. Examples of weight-bearing exercise include aerobics, dancing, gardening, hiking, jogging, stairclimbing, tennis, walking, and weight training. Generally, athletes have a bone density that is 13 percent higher than that of nonathletes. Conversely, complete bed rest leads to serious bone loss.
Bones are living tissues that respond to exercise by becoming stronger, just like muscles. Physical activity early in life helps you develop higher peak bone mass. The more bone mass you have before age 25 to 30, the healthier you will be in later years, when your body gradually loses bone.
As you get older, the benefits of activity for augmenting bone mass are not as great, but doing weight-bearing exercise is still important. A program that builds muscle and improves balance and coordination can generally maintain bone density and help prevent falling, which is a major concern in older people. Falls raise the probability of fracturing a bone in the hip, spine, wrist, or another part of the skeleton. Fractures affect quality of life, result in loss of independence, and can even lead to premature death.
Older adults should engage in at least 30 minutes of moderate physical activity daily and include a mix of weight-bearing exercise, strength training, and balance training. Exercise combined with adequate calcium and vitamin D intake can help reduce age-related bone loss. However, excessive exercise can be bad for bones and especially harmful to joints.