Fk. Lotgering et al., RESPIRATORY AND METABOLIC RESPONSES TO ENDURANCE CYCLE EXERCISE IN PREGNANT AND POSTPARTUM WOMEN, International journal of sports medicine, 19(3), 1998, pp. 193-198
This study was designed to determine whether endurance cycling respons
es in pregnancy differ from those postpartum. We studied 16 women long
itudinally at similar to 32 wk pregnancy and similar to 10 wk postpart
um, We measured heart Fate (HR), O-2 uptake ((V) over dot O-2), CO2 ou
tput ((V) over dot CO2), minute ventilation (V) over dot E and plasma
concentrations of substrates and of catecholamines at rest, during max
imal testing, and during similar to 35-40 min of cycling at similar to
70-75% (V) over dot O-2peak. Endurance exercise time and power were 3
7.6+/-1.0 min and 124+/-8 W in pregnancy, similar to values observed p
ostpartum. HR and respiratory responses near the end of endurance exer
cise were also unaffected by gestation, with pregnancy values of 173+/
-3bpm, 1.87+/-0.07 L/min (V) over dot O-2 and 1.68+/-0.07 L/min (V) ov
er dot CO2 except that (V) over dot E at 70.0+/-3.5 L/min was 14% high
er than postpartum; plasma concentrations of free fatty acids (404+/-6
2 mu mol/L), glucose (3.34+/-0.17 mmol/L), and lactic acid (4.51+/-0.5
0 mmol/L) were lower than postpartum by 9, 24, and 19%, respectively;
catecholamine concentrations were not different from those determined
postpartum, We conclude that pregnant women are equally capable as are
postpartum women to perform similar to 40 min of cycling at 70-75% (V
) over dot O-2 peak, and that the physiologic responses to endurance e
xercise are largely independent of gestation.