The astounding form of Belgian tennis player Clijsters at the US Open has once again brought to the fore the issue of motherhood and sports. Many experts believe the surge of hormones during child birth actually benefits sportswomen.
James Pivarnik, a professor of kinesiology and epidemiology at Michigan State University, found in studies that the increased blood volume during pregnancy increased the oxygen capacity of muscles by 30%.
Greg Whyte, professor of applied sport and exercise science at Liverpool John Moores University, agreed that this could improve aerobic capacity, enabling a woman to run, cycle or swim at a certain pace for longer.
"A surge in hormones predominantly progesterone and oestrogen, but also the male hormones including testosterone could increase muscle strength," he added. "Increases in other hormones like relaxin, which loosens the hip joints to prepare a woman for birth, could also improve joint mobility to a beneficial degree."
In 1997 a paper in the Scandinavian Journal of Medicine and Science in Sports said that giving birth helped increase endurance in cross country runners and skiers. All this may just prompt some sportswomen to embrace motherhood with open arms!