Lynch A, Goodman L, Choy P, Dawson L, Newnham J, McDonald S and Blanksby B.
Maternal aerobic fitness was measured before, during and after a 12 week program of swimming training during the second trimester of pregnancy in 23 sedentary women. A control group of 11 women who did not swim was measured for comparision. The training involved 3 40-minute swimming sessions weekly, intensity was planned to produce heart rate responses (HRR) of 65-70% of estimated maximum. The distance swum almost doubled in the intervention group over the 12 week period and measures of submaximal fitness were significantly higher in the intervention group compared to the control group. All subjects remained healthy with no adverse effects on mother or baby reported.
Research in Sports Medicine, 2007, 15(1), 33-45