Journal of Applied Physiology, Vol 48, Issue 1 34-40, Copyright © 1980 by American Physiological Society
Effects of exercising rats during pregnancy
N. C. Wilson and C. V. Gisolfi
To determine the effects of exercise during pregnancy on the cardiovascular
system of their progeny, female Sprague-Dawley rats were assigned to one of
four groups: 1) trained-nontrained (T-NT) animals who ran for 7 wk at 35
m/min before but not during pregnancy; 2) T-T animals who ran at 35 m/min
before and at 32 m/min during pregnancy; 3) control (C) animals who did not
exercise; and 4) NT-T animals who only ran (16 m/min) during pregnancy.
Significant increases in skeletal muscle cytochrome found between exercised
(NT-T, T-T) and nonexercised (C, T-NT) mothers; C animals had significantly
lower maximal oxygen consumption (VO2max) values than T-T animals at the
end of pregnancy. Offspring mortality was greater (P less than 0.05) in the
T-T compared with the C group during the 28 days following birth. Maternal
exercise had no significant influence on VO2max in the offspring or on
myocardial blood flow when these animals were ventilated with either
hypoxic (10% O2) or normoxic (21% O2) gases. Right ventricular fiber areas
were smaller (P less than 0.05) in T-T and NT-T animals compared with the
T-NT group; no significant changes were observed in the left ventricle.
Capillary density and fiber-to-capillary ratios were not different in
either the right or left ventricle. These results indicate that mild or
heavy exercise does not influence VO2max, coronary blood flow in response
to stress, or myocardial structure in the male offspring of rats trained
during pregnancy.
