As a story in the New York Times reports, some people respond well to aerobic exercise, while others seem to benefit less or not at all. There are studies that show there is a genetic component to this: various exercise traits (and the drive to exercise at all) do certainly run in families. A new study has scanned to genomes of 473 individuals subjected to the same 5-month exercise regime and found that particular SNPs (pronounced “snips;” we’ve talked about these before, see this post) are associated with a robust response to exercise. From the New York Times story:
The researchers looked at 324,611 individual snippets over all. Each of the volunteers had already completed a carefully supervised five-month exercise program, during which participants pedaled stationary bicycles three times a week, at controlled and identical intensities. Some wound up much fitter, as determined by the increase in the amount of oxygen their bodies consumed during intense exercise, a measure called maximal oxygen capacity, or VO2 max. In others, VO2 max had barely budged. No obvious, consistent differences in age, gender, body mass or commitment marked those who responded well and those who continued to huff and struggle during their workouts, even after five months.
But there was a divergence in their genomes. The researchers identified 21 specific SNPs, out of the more than 300,000 examined, that differed consistently between the two groups. SNPs come in pairs, since each of us receives one paternal copy and one maternal copy. So there were 42 different individual versions of the 21 SNPs. Those exercisers who had 19 or more of these SNPs improved their cardiorespiratory fitness three times as much as those who had nine or fewer.
One interesting question that is raised by this research is: if one finds that they do not have the advantageous SNPs, will they simply not try to exercise at all?
Our keynote speaker John Hawks describes this study and harps on the New York Times reporting on his blog.