Subacute and long term effect of swimming training on blood pressure in young and old spontaneously hypertensive rats.
The effects of swimming training (three weeks' training with the duration increasing up to a maximum of 180 min per day, at a water temperature of 36 degrees C) on arterial blood pressure were studied in 4, 11, and 18 month old spontaneously hypertensive rats. In addition, in the 11 month old rats the change in blood pressure after individual exercise was determined. The significance of a training induced loss of body weight in lowering blood pressure was assessed by pair feeding of sedentary age matched spontaneously hypertensive rats. Blood pressure was reduced by approximately 50 mmHg within 8-10 days, except in the oldest rats, which tolerated the physical activity poorly and had, if any, only a moderate fall in blood pressure. It was possible to distinguish between subacute transient effects lasting for not more than one day and long term effects. Blood pressures were 20-25 mmHg lower after individual swimming routines than those before exercise when measured on the ninth day of the training programme. On cessation of training, blood pressures approached those of sedentary rats within two weeks. It seems that the loss of body weight was of minor importance in lowering blood pressure under these experimental conditions.
Noma
K
K
Physiology Institute II, University of Tübingen, Federal Republic of Germany.
Rupp
H
H
Jacob
R
R
D000375:Aging / Q000502:physiology*; D000818:Animals; D001794:Blood Pressure; D001835:Body Weight; D006339:Heart Rate; D006973:Hypertension / Q000503:physiopathology*; D005082:Physical Exertion; D051381:Rats; D011918:Rats, Inbred SHR; D013550:Swimming; D013997:Time Factors