New study shows that dopamine may increase runners motivation
“Runner’s high” phenomenon is characterized by a sense of freedom and extra energy, thought to be produced by endorphins in the pituitary gland. Endorphins are known to trigger a positive feeling in the body.
New study at the University of Montreal Hospital Research Centre (CRCHUM) showed that the joy of running and the high motivation runners usually have is influenced also by a neurotransmitter called dopamine. Dopamine is the precursor of adrenaline.
Dopamine is linked to leptin, a hormone secreted by the adipose tissue in our bodies that also controls satiety sensation, influences exercise endurance, regulates energy balance and increases motivation, so that the body can benefit from its efforts.
“We discovered that the rewarding effects of endurance activity are modulated by leptin, a key hormone in metabolism. Leptin inhibits physical activity through dopamine neurons in the brain. The more fat there is, the more leptin there is and and the less we feel like eating. Our findings now show that this hormone also plays a vital role in motivation to run, which may be related to searching for food,” lead author Dr. Stephanie said about study findings.
Researchers measured voluntary wheel running in laboratory mice compared with that of mice who suffered genetic suppression of signal transducer and activator of transcription-3 (STAT3) molecule, activated by leptin and linked to motivation.
“Mice that do not have the STAT3 molecule in the dopaminergic neurons run substantially more. Conversely, normal mice are less active because leptin then activates STAT3 in the dopamine neurons, signalling that energy reserves in the body are sufficient and that there is no need to get active and go looking for food,” explained Maria Fernanda Fernandes, first author of the study.
The same process applies to humans: “Previous studies have clearly shown a correlation between leptin and marathon run times. The lower leptin levels are, the better the performance. Our study on mice suggests that this molecule is also involved in the rewarding effects experienced when we do physical exercise. We speculate that for humans, low leptin levels increase motivation to exercise and make it easier to get a runner’s high,” Dr. Stephanie Fulton concludes.