High-intensity exercise is more effective at suppressing hunger than moderate levels, especially in females, according to recent research.
The study, focusing on the “hunger hormone” ghrelin, suggests that such vigorous activity might be a critical component of weight management strategies.
Impact of Exercise Intensity on Appetite
A new study published today (October 24) in the Journal of the Endocrine Society suggests that intense exercise is more effective at reducing hunger in healthy adults than moderate exercise, with women showing a particularly strong response.
The research focused on how different levels of exercise intensity affect ghrelin, a hormone known as the “hunger hormone” because it plays a key role in regulating appetite.
“We found that high-intensity exercise suppressed ghrelin levels more than moderate-intensity exercise,” explained lead author Kara Anderson, Ph.D., from the University of Virginia and the University of Virginia Health System in Charlottesville, Virginia. “In addition, we found that individuals felt ‘less hungry’ after high-intensity exercise compared to moderate-intensity exercise.”
Gender Differences in Hormonal Responses
Ghrelin circulates in two forms—acylated (AG) and deacylated (DAG)—both of which influence appetite. However, data on how exercise intensity impacts these forms, particularly in relation to appetite suppression, is limited and has mostly focused on men.
To address this shortfall, the study examined eight males and six females. Participants fasted overnight and then completed exercises of varying intensity levels, determined by measurements of blood lactate, followed by self-reported measurements of appetite.
Females had higher levels of total ghrelin at baseline compared with males, the study noted. However, only females demonstrated “significantly reduced AG” following the intense exercise, according to the findings.
Exploring the Physiological Effects of High-Intensity Exercise
“We found that moderate intensity either did not change ghrelin levels or led to a net increase,” the study noted. These findings suggest that exercise above the lactate threshold “may be necessary to elicit a suppression in ghrelin.”
Researchers also acknowledged that more work is needed to determine the extent to which the effects of exercise differ by sex.
Ghrelin has been shown to have wide-ranging biological effects in areas including energy balance, appetite, glucose homeostasis, immune function, sleep, and memory.
Practical Implications for Exercise and Weight Management
“Exercise should be thought of as a ‘drug,’ where the ‘dose’ should be customized based on an individual’s personal goals,” Anderson said. “Our research suggests that high-intensity exercise may be important for appetite suppression, which can be particularly useful as part of a weight loss program.”
Reference: “The Impact of Exercise Intensity and Sex on Endogenous Ghrelin Levels and Appetite in Healthy Humans” 24 October 2024, Journal of the Endocrine Society.
Other study authors include Tana Mardian, Benjamin Stephenson, Emily Grammer, Macy Stahl, Nathan Weeldreyer, and Sibylle Kranz of the University of Virginia; Zhenqi Liu and Kaitlin Love of the University of Virginia Health System; and Jason Allen and Arthur Weltman of the University of Virginia and the University of Virginia Health System.
This research received financial support from the National Institute of Diabetes and Digestive and Kidney Diseases and the University of Virginia’s School of Education and Human Development.