Why exercise works

We know the health benefits of physical activity. Better BMI, lower levels of LDL and higher levels of HDL, improved blood pressure and heart rate, more efficient cardio functioning, lower risk of cardiovascular diseases and diabetes. In addition, there are psychological benefits from exercising. It’s not only responsible for positive outcomes such as lower levels of stress and better life satisfaction in the general population, it’s also been shown to be effective in helping to improve psychological mood and mental wellbeing among those with depression (Ströhle, [2009] offers a comprehensive literature review on the subject).

And we know the health benefits of eating healthy. Health magazines and newspaper articles extol the virtues of making healthier eating choices, while there’s plenty of research evidence that increasing one’s daily intake of multigrains and/or greens plays a protective role against cancer, cardiovascular diseases, and obesity.

But knowing and doing are two different things. Perhaps it might be helpful to understand why exercise and healthy eating achieves these things. For one thing, it appears that exercise helps the body process fat more efficiently. A recent news article, “Altered states” (Economist, July 2013) highlights the finding that fats cells of people who exercise behave differently from those of people who exercise rarely (Ronn et al., 2013). For another, increased intake of greens appears to increase gut bacteria associated with healthy metabolism and decrease gut bacteria associated with obesity. The recent news article, “Wider understanding” (Economist, September 2014) explains that a high glycaemic diet impairs insulin functioning, unlike a low glycaemic diet (driven by the intake of multigrains) which in turn is protective against obesity.

But knowing the health benefits of exercise and healthy eating is half the equation: you still have to get out there and do it!