July 13, 2003 -- Bethesda, MD -- Skeletal bone is living tissue and requires constant turnover, accomplished through a process that repairs damage and alters bone mass in response to needs. For most of the time, the skeleton responds to mechanical loading generated though exercise by increasing bone mass and strength. In human studies, bone development and bone mechanical properties are indicated by bone mineral density (BMD). Physical activity with weight-bearing has been shown to improve BMD. Conversely, previous studies have reported that non-weight-bearing exercises such as swimming does not have an equivalent beneficial effect on BMD. The BMD in people who have participated in a non-weight-bearing swimming exercise program has been shown to not be significantly different from the BMD in respective control groups. Because of ethical issues, measurements of bone development in human studies are typically limited to noninvasive radiography or serum bone marker assays. Thus, it is difficult to investigate the effects of exercise mode on bone by using these techniques.

There is difficulty in equalizing the energy expenditure or total work of different modes of exercise, which has lead to a lack of studies in this area. There have been studies that assessed the effects of either weight-bearing or non-weight-bearing exercise on bone separately, which determined that non-weight-bearing exercises, generally swimming, have a positive influence on bone strength in ovariectomized rats, osteotomized rats, and growing rats. The published findings suggest that water sports could enhance the mechanical properties of bone under specific conditions, and direct comparison of its effects with those of weight-bearing exercise would be useful.

A New Study

Accordingly, a team from Taiwan controlled the relative training intensities of two different exercise modes in an attempt to equalize the energy expenditure between the two training programs. They hypo
'"/>

Contact: Donna Krupa
djkrupa1@aol.com
703-527-7357
American Physiological Society
29-Jul-2003

Page: 1 2 3 4
Related biology news :

1. Swimming Proficiency Of Marine Mammals Ranks Them Among The Worlds Elite Animal Athletes
2. Spraying Water Containing Airborne Bacteria Found At Some Indoor Swimming PoolsCan Cause "Lifeguard Lung" Following Long-Term Exposure
3. Unicellular organisms contribute more nitrogen to ocean that reported earlier
4. Does antibiotic use contribute to allergies?
5. Common virus may contribute to uncommon bone disease in children
6. Protein inhibits cell growth, may contribute to breast cancer
7. Suicide proteins contribute to sperm creation
8. Could a specific protein contribute to erectile dysfunction for the diabetic and obese?
9. Molecule identified that contributes to essential cell functioning process
10. Deciphering how arteries contribute to hypertension
11. UC Riverside scientists contribute to study that unveils genome sequence of bread mold