In addition to its other potential health benefits, intermittent fasting may cause hormone changes that boost one’s motivation to exercise. The findings were detailed in a study recently published in the Journal of Endocrinology, where researchers explain that intermittent fasting — as well as general meal restriction — boosts the ‘hunger hormone’ ghrelin and its ability to boost exercise motivation.
Humans have two hormones that play important roles in appetite and satiation: ghrelin, the ‘hunger hormone,’ and leptin, the hormone that eliminates the appetite after eating. When someone goes a number of hours without eating, the amount of ghrelin in their blood increases; after eating, the levels of this hormone plummet.
According to the latest study, high levels of ghrelin may increase exercise motivation in addition to appetite — something that makes sense when you consider that acquiring food requires effort. Past research has found links between ghrelin and increased endurance during exercise; beyond that, many people have reported temporary surges in energy and trouble sleeping when fasting or following diet protocols that imitate fasting.
Excerpted from Slash Gear