I hate running.
But I like to stay in shape and, well, running is the most convenient, cheapest form of exercise. So, I lace up and run.
When I first got pregnant, I thought: “Sweet, now I have an excuse to stop running!”. But, alas, the inner athlete in me refuses to die with this expanding belly.
But running falls into the same trap as with most pregnancy “advice” (both solicited and unsolicited) – one person will say “you need to slow down!” and the next will say “didn’t so-and-so run a marathon when she was 8 months pregnant?”.
The wide world of internet advice seems to stay a bit vague on this issue. More than once, I have seen or overheard the magic number of “140” (bpm for maternal heart rate) floating around despite the fact that a little bit of investigation suggests that this recommendation was nixed in 1994 by the American College of Obstetricians and Gynecologists. But mostly, the advice is simple: if you are overheating, if you are throwing up, if you are bleeding or passing out, stop your workout. Really? No shit.
Ok, on to the science.
A lengthy 2003 review by Artal and O’Toole in The British Journal of Sports Medicine scanned the data available throughout the scientific literature and found evidence (and lack of evidence) for the pregnant exercise dilemma. The authors conclusion: “exercise has minimal risk and confirmed benefits for most women”.
Wait, do I fall into the category of “most women”? Not going to flatter myself, I probably do, but just in case…
A 2012 study by Szymanski and Satin published in the American Journal of Obstetrics and Gynecology categorized women into their exercise regiments and measured parameters of both mama and womb baby. Pregnant ladies ranging from 28-32 weeks were split into three groups: inactive, moderately active, and highly active. They were then tested before and after moderate and vigorous exercise (luckily for inactive group, they weren’t pushed to the vigorous stage so this category only contains those who exercised a bit before the test). Measuring maternal heart rate (MHR), fetal heart rate (FHR), and indices of circulation making it between the two (via measurements from fancy Doppler sonography), the authors reached the conclusion that moderate exercise, even for the inactive preggos, does not change a single thing for the baby. Only vigorous exercise caused changes – slight increase in FHR but a decrease in Doppler indices. Interestingly, this decrease actually indicates improved circulation to the baby, making this change “not clinically significant”.
Here’s a category that I definitely do not fit into: elite athlete. But just in case, I checked out an article entitled “Fetal Wellbeing May be Compromised During Strenuous Exercise Among Pregnant Elite Athletes”, a 2012 study by Salvesen et al, published in The British Journal of Sports Medicine. However, I quickly lost attention when I realized that this study was conducted on SIX women and the only result they found (increased FHR) occurred when these Olympians, training for endurance events, were pushed to >90% of their maximal heart rate. So, if you are training to run a marathon in 2 1/2 hours, you might want to shoot for a 3 hr pace instead when you are running for two.
I guess I don’t have to worry about that one.
And… it looks like I have no excuse.
Time to get off my butt and lace up.