When Working Out Doesn’t Work

The science behind why some people get fitter than others.

Not everyone who exercises achieves the same gains in fitness or equal health benefits. Researchers from Japan believe they have a possible answer. They have found a liver protein called selenoprotein P that is released into the blood of people who fail to respond to exercise.

Selenoprotein P works by limiting glucose (sugar) transport into muscles. This might help explain why up to 20 percent of people with type 2 diabetes (adult-onset diabetes) have little or no improvement in blood sugar control with regular exercise.

There are currently no tests for selenoprotein P levels in the blood. So it’s not yet possible to determine who will benefit the least from exercise. Despite this, the odds remain that exercise works for most people.  If not for fitness and blood glucose control, then there are the many emotional and brain benefits of regularly exercising.

Written by Professor David Cameron-Smith, article and images sourced from Les Mills