Harvard professor debunks the biggest exercise myths | Daniel Lieberman

Heavy weights will bulk me up.

You may have heard this in the weight room from time to time. Some people, particularly women, are concerned that adding strength training will build muscle bulk to the point they will look like a bodybuilder. This is not true.

For a female to bulk up, she would have to do a lot of strength training — and I mean a lot. Women do not have enough testosterone to bulk up the way men do. Competitive female bodybuilders follow strenuous diet and workout programs that likely feature use of various muscle-building supplements.