Exercise is an extremely important factor both in preventing osteoporosis and in decreasing the risk of fractures in those with osteoporosis. Almost any type of physical activity has some benefits to health. In terms of osteoporosis, however, the best types of activities are those that result in increased bone mass, as well as decreasing the risk of fracture by improving muscular strength, balance, and co-ordination.
Osteoporosis is not an inevitable part of aging. Bone mass, muscle strength, flexibility and co-ordination all improve with exercise.
To better understand the relationship between exercise and your bones, you must first know what bones are and aren’t. Bone is living tissue, not a lifeless structure that only supports your muscles and flesh. In fact, bone, like other body tissue, changes throughout a person’s life.
During childhood and adolescence, bones grow primarily in size. During late adolescence and early adulthood, although bone is no longer increasing size, it continues to gain density until it reaches “peak bone mass.” Peak bone mass is a term used to describe the point at which bones have achieved their maximum strength and density. This occurs some time around the age of 20. After that, bone mass usually stabilizes for several years and then starts to decrease.
In general, you lose about one per cent of your total bone mass each year. In women, the rate of loss increases dramatically after menopause to two to three per cent per year. This loss in bone mass occurs because, as you age, new bone is not laid down at the same rate as older bone is lost. This can result in a reduction in the density of the bones, referred to “osteoporosis.”
Please do not think that the bones actually become thinner and change shape. If I have a piece of oak and piece of pine that are exactly the same shape and size, the piece of oak is much stronger and has a greater density than the pine. Your bones may start out as strong as oak, but as you age, the bones can lose density and end up more like soft wood such as pine.
Physical activity has been shown to be an important factor in increasing our peak bone mass and reducing the rate of bone loss with age. While all physical activities are beneficial, certain kinds are better for the bones than others. The best type of exercise for increasing bone mass and reducing the rate of age related bone loss is “weight-bearing” activity. This is exercise that requires you to support your entire body weight. Walking, running, and games and sports such as badminton, bowling, tennis, basketball and volleyball are all examples of weight-bearing exercises.
However, my favourite form or “weight-bearing” exercise is called “resistance exercise.” A common form of resistance exercise is weight training, which is done with barbells or dumbbells and/or various apparatuses available at gymnasiums and fitness centres. In addition to their effect on bone mass, muscular strengthening exercises will increase your co-ordination and balance, which will make you less likely to fall and fracture any bones.
While you cannot directly observe the weight-bearing and resistance exercises strengthening your bones, something very important is happening. The skeletal system is no different than any other system in your body. It adjusts to physical activity and also a total lack of it. Your bones respond to an increased load (pressure on the bones when exercising) by increasing in strength, density and mass, or at least by returning bone that was previously lost.
The reverse is also true: your bones respond to a decreased load by decreasing in bone mass. For example, studies of the racket arms of tennis players show a much higher bone mass than the non-racket arm. This is because the racket arm encounters much more resistance.
Finally, there have also been studies with osteoporotic women doing resistance exercises that showed that they not only prevented bone loss but may also have increased their bone mass.
On a final note, exercise alone cannot increase your bone mass. It is well known that calcium is one of the key ingredients that the body uses to build bone. Another well known fact is that vitamin D is required in your diet in order to assist the calcium to be absorbed into your body from the digestive tract.
