Study: Single workout can boost metabolism for days

WASHINGTON – Chinese and American scientists found that a single workout could activate neurons in mice that influence metabolism for up to two days and those effects last longer with more training.

The study, published on Tuesday in the journal Molecular Metabolism, offered new insight into the brain’s potential role in fitness and perhaps a new target for developing therapies that improve metabolism.

“It doesn’t take much exercise to alter the activity of these neurons,” said Kevin Williams, a neuroscientist at the University of Texas Southwestern, a co-author of the paper.

“Based on our results, we would predict that getting out and exercising even once in a semi-intense manner can reap benefits that can last for days, in particular with respect to glucose metabolism,” said Williams.

Researchers, including the paper’s first-author He Zhenyan from Guangzhou-based Zhujiang Hospital, measured the effects of shortand long-term exercise on two types of neurons that comprise the melanocortin brain circuit. Both humans and mice have this circuit.

One of the neuron types is associated with reduced appetite, lower blood glucose levels, and higher energy burning when activated while the other type increases appetite and diminishes metabolism when activated, according to the study.

They found that a single bout of exercise for mice could boost the activity of energy-burning neurons and inhibit the counterpart one for up to two days and those changes can last longer with more training.

A single workout consisting of three 20-minute treadmill runs led to a decrease in appetite that lasted up to six hours, according to the study.

“This result may explain at the neural circuit level why many people don’t feel hungry immediately after exercise,” said Williams.

Previously, the melanocortin circuit is known to be altered through feeding or fasting but not yet linked to exercise.

The findings also lend clues to potential treatments to improve glucose metabolism in patients with diabetes.

“It is possible that activating melanocortin neurons may hold therapeutic benefits for patients one day, especially for diabetics who need improved blood-glucose regulation,” said Williams.