Previously we鈥檝e discussed women who ran marathons while pregnant, including a 27-year-old who ran the Chicago Marathon , and a 44-year old who ran the 鈥攁nd won鈥攚hile three months .
Doctors said women who were already endurance training before pregnancy may continue as long as it鈥檚 not uncomfortable. Even non-marathoners are encouraged to get cardio exercise in, walking at least 30 minutes, five times a week.
But while doctors generally give the same advice about weight lifting鈥攖hat a woman may continue her pre-pregnancy regimen, as long as it鈥檚 not uncomfortable鈥攖here is one additional concern.
鈥淭he concern is the Valsalva of when you鈥檙e holding your breath and you鈥檙e really grunting and pushing,鈥 says , Director of the Center for Physical Activity and Health at Michigan State University. The Valsalva maneuver is performed by trying to exhale forcefully against a closed airway, like when attempting to equalize ear pressure by closing the mouth, pinching off the nose, then blowing out. Weight lifters often do the same thing, holding their breath to lift heavy objects.
The Valsalva maneuver reduces the heart鈥檚 output, briefly reducing blood flow to the body. 鈥淚t鈥檚 not good at any time, but particularly during pregnancy,鈥 Pivarnik says. 鈥淲hen you鈥檙e lifting a lot, even if you try not to hold your breath, you almost can鈥檛 help it. The concern is it could temporarily impede the blood flow to the fetus, or the blood flow to the mom and she could faint.鈥
That said, weight lifting is not completely off the table. In fact, there鈥檚 some anecdotal evidence that women who lift weights may have an easier time in delivery. 鈥淧eople who lift weights won鈥檛 get as tired, and they understand what it feels like to be pushing,鈥 Pivarnik says.
Like with cardiovascular exercise, researchers are a long way off from prescribing acceptable weight training practices during pregnancy because of ethical concerns; they can鈥檛 make several thousand pregnant women lift heavy weights to see what it does to their babies.
You鈥檝e surely read about . The 35-year old former bodybuilder stirred up national controversy after posting photos of herself lifting heavy weights at a CrossFit gym while eight months pregnant. It鈥檚 possible Ellison鈥檚 regimen works for her and her baby, because proper pregnancy training can only be determined between each woman and her doctor.
The bottom line: The main concern about weight training while pregnant is breath holding. If you must hold your breath to lift a weight, it鈥檚 probably a good idea to back off the poundage until you can breathe easily.