Women who work out throughout their pregnancy are more likely to have a smoother and shorter childbirth, new research suggests.
Regular pelvic floor exercises, jogging and weight training shaves around 50 minutes off labour, according to the Daily Mail.
Researchers monitored 508 women from their first trimester - half of whom were assigned to three one-hour workouts a week, while the others had antenatal counselling.
By the time the women gave birth, they found a clear correlation between length of labour and regular exercise.
Experts say it is likely down to the fact that physically fit women have stronger muscles to help them push their way through childbirth.
They said they hope these findings encourage pregnant women to get moving, since the idea that fitness could be dangerous was rejected by scientists long ago, and we now know exercise is key to preventing life-threatening complications during labour.
"We're no longer promoting the idea of resting and putting your feet up," Kara Whitaker, an exercise scientist at the University of Iowa, told the New Scientist.
"Labour and delivery is a very physically taxing event," she said.
"If you are physically stronger, you may have more muscle for the pushing stage."
In the study, conducted by Ruben Barakat at the Technical University of Madrid, more than half the women gave birth naturally.
Of those, there was a huge disparity in the average labour time between those who had regularly exercised and those who hadn't.
The exercise group had an average labour of seven hours and 30 minutes. Those in the counselling group - who learned about exercise benefits but didn't do the same workout regime - had an average labour of eight-and-a-half hours.
According to Professor Barakat, "these results confirm the huge potential of physical exercise as an exceptional preventive element of anomalies and diseases that can establish the health of future populations in the case of pregnancy processes."
The team is now in the initial stages of more trials, this time in Argentina and Canada, to assess how exercise affects the placenta.
Aside from providing a morsel of relief to pregnant women, the findings could also have broader implications for childbirth and maternal mortality trends, particularly in the US.
America has the highest rate of maternal mortality in the developed world. While that used to be the result of complications in the operating room, most deaths today are caused by underlying heart conditions that affect the mother's blood and placenta.
Obstetricians say a major push to encourage exercise during pregnancy - and before pregnancy - could be a game changer for curbing the staggering death rates.