When Elle Purrier St. Pierre, the 27-year-old Olympian and multiple American record holder, announced her pregnancy a few weeks ago, fans were surprised. So did I, although I recently wrote about a study suggesting that pregnancy does not alter the career trajectory of elite runners. Old habits die hard and the impulsive assumption that motherhood will derail an athlete’s career remains deeply ingrained, making another recently published study on the impact of pregnancy on life all the more important. training and performance of elite runners.
A team of researchers in Canada led by Francine Darroch of the University of Ottawa and Trent Stellingwerff of the Canadian Sport Institute Pacific recruited 42 elite long-distance runners, more than half of whom had competed in the Olympics or World championships over distances ranging from 1,500 meters to the marathon. Using their training diaries, the runners reported how their training changed before, during and after their first pregnancy, which occurred at ages ranging from 20 to 42. The researchers also analyzed the evolution of their results in publicly available competitions.
The results, published in Medicine and science in sport and exercise, should reassure Purrier St. Pierre fans. Among runners who said they intended to return to the highest levels of competition after pregnancy, there was no significant difference between their running times before and after pregnancy. About half of them got better and the other half got worse, which in the elite sports world is a pretty decent rating.
That’s great news, but the detailed training data shared by athletes is even more enlightening. Experts are understandably cautious when it comes to giving advice to women who are accustomed to very high levels of exercise and want to maintain those levels during pregnancy. All of the women in Darroch’s study had safe and successful deliveries. We shouldn’t read this too much, because women who didn’t probably wouldn’t have signed up for the questionnaire-based study. Yet training data offers real-world context of athletes who have trained through successful pregnancies.
The data covers five key time points: one year before pregnancy, during the first, second and third trimesters, and one year after pregnancy. Overall, they continued to run a similar number of days throughout pregnancy (6, 6, and 5 in all three trimesters), but gradually shortened the duration of runs and greatly reduced the number of runs d medium and high intensity.
Here is their average mileage at those five points:
At the same time, they ramped up cross-training, presumably for low-impact activities like the elliptical or swimming, so total training time remained similar. Here’s how it evolved:
After pregnancy, women waited an average of three weeks before resuming cross-training, and six weeks before resuming running, but with significant individual variability. They were back to about 80% of pre-pregnancy training levels 14 weeks postpartum, again with a lot of variability (one standard deviation of 11 weeks). This seems relatively conservative compared to post-pregnancy exercise guidelines, which suggest that it’s generally safe to start exercising a few days after giving birth. But there’s probably a difference between going out for a brisk walk and a “workout” of the type that elite athletes would find useful to record in their logbook.
So, how was their return to running? Exactly half of them dealt with postpartum injuries, encompassing stress fractures, sprains or ruptures of tendons and ligaments and other setbacks. None of the training data predicted who was injured and who was uninjured. This is likely because the sample was too small and too diverse to detect subtle differences, and possibly also because the athletes were experienced enough to avoid obvious errors.
A statistically significant difference emerged: among those who attempted to return to elite performance, those who injured themselves did worse within one to three years of the birth of their child. In fact, those who managed to avoid injury actually improved by 3.6%, on average, from their pre-pregnancy best. This is a good reason to err on the side of caution when returning to training.
It should be remembered that the women in this study are a rarefied group. They were already elite endurance athletes before they got pregnant, so – as in the case report published a few years ago about a 28-year-old Sherpa runner and guide who hiked Everest Base Camp. , at 17,000 feet above sea level, while 31 weeks pregnant — don’t take their mileage or workout habits as goals for everyone. Current guidelines for the general population suggest that pregnant women should aim to be physically active most days and accumulate at least 150 minutes of moderate exercise per week. But if you’re used to doing much more than that, consider this data your green light to continue, within reason and with appropriate adjustments.
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