Exercise is Good for the Fetus

May conducted a study of the effects of maternal exercise on the fetus. Comparing sedentary pregnant women to those who engage in moderate-intensity aerobic exercise for at least thirty minutes three times a week, May found that fetuses show the same beneficial effects of cardiovascular training as do their physically active mothers: their heart rates are significantly lower, and their heart-rate variability is greater, than those of fetuses of mothers who don’t exercise. [...] Exercise may...

 Neoteny in Humans

...the concept of "neoteny"—the retention of juvenile features into adult life. It is a commonplace of human evolution that the transition from Australopithecus to Homo and from Homo habilis to Homo erectus and thence to Homo sapiens all involved prolonging and slowing the development of the body so that it still looked like a baby when it was already mature. The relatively large brain case and small jaw, the slender limbs, the hairless skin, the unrotated big toe, the thin bones, even the ex...