Histomorphometry of long bone growth plate in swimming rats.

In exercises involving running, muscle power and gravitational forces act together to affect bone mass in accordance with Wolff's law. However, the direct effect of muscle activity on bones in non-weight-bearing activities, such as swimming, has not been explored. Previous data indicate that swimming exerts a positive effect on bone growth and development in young rats.

The effect of swimming on bone modeling and composition in young adult rats.

The purpose of this study was to investigate the adaptability of long bones of young adult rats to the stress of chronic aquatic exercise. Twenty-eight female Sabra rats (12 weeks old) were randomly assigned to two groups and treatments: exercise (14 rats) and sedentary control (14 rats) matched for age and weight. Exercised animals were trained to swim in a water bath (35 degrees +/- 1 degree C, 1 hour daily 5 times a week) for 12 weeks loaded with lead weights on their tails (2% of their body weight) (BW).

Effect of swimming on bone growth and development in young rats.

The effect of chronic swimming on bone modelling was studied. Forty female Sabra rats (5 weeks old) were randomly assigned to the following experimental groups: 30 rats were trained to swim (water bath 35 +/- 1 degree C, one h daily, five times a week) for 20 weeks--20 of them loaded with lead weights (1% body weight) while the rest (10 animals) swam load free. Ten sedentary rats matched for age and weight served as controls.

The effect of swimming activity on bone architecture in growing rats.

The effect of non-habitual physical activity on bone architecture in the rat humeral shaft was examined. Two groups of rats were trained to swim for 1 h a day, for 20 weeks, at two training levels. The control group consisted of sedentary rats.

Cardiac output distribution in thermally dehydrated rodents.

The effect of thermal dehydration (37 degrees C) on the integrated response of the circulation was studied in conscious laboratory rats and in the desert species Psammomys obesus, the latter being studied prior to and following acclimation to heat. Cardiac output (CO) and its distribution were measured using labeled microspheres with the reference organ technique. At low dehydration (7-9% body wt loss) rats showed peripheral vasodilation coincidentally with splanchnic vasoconstriction, whereas the desert species exhibited an increased CO and peripheral vasodilation with no change in splanchnic blood perfusion.