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What Happens When One Twin Exercises and the Other Doesn’t - Outside Online

All the twin pairs came in for physical examinations, and the results were pretty much what you’d expect. The exercising twins had higher VO2 max (38.6 vs. 33.0 ml/kg/min), smaller waist circumference (34.8 vs. 36.3 inches), lower body fat (19.7 vs. 22.6 percent), significantly less abdominal fat and liver fat, and so on. The study is free to read if you want to dig further into the details, but the results aren’t surprising. Exercise clearly improves a bunch of health parameters, and genes clearly matter too—after all, the differences aren’t that big.