Adding interval exercise to a low-calorie diet suppressed acylated ghrelin and reduced hunger compared to dieting alone in 26 women with obesity over 2 weeks.
Ghrelin suppressed P=0.04Interval exercise during caloric restriction suppressed post-meal acylated ghrelin vs diet alone
What the researchers found
LCD+INT suppressed post-prandial acylated ghrelin (P=0.04) and attenuated fasting hunger (P=0.05) compared to energy-matched LCD alone in women with obesity.
Why it matters
The biggest barrier to dieting is hunger. Interval exercise suppresses the hunger hormone ghrelin, potentially making calorie restriction more sustainable for weight loss.
The numbers in context
26 women; BMI 37.3; 2 weeks; acylated ghrelin suppressed (p=0.04); hunger attenuated (p=0.05); PYY increased (p<0.001)
How the study worked
RCT: 26 women with obesity randomized to LCD (1,200 kcal/day) or LCD+INT (diet + 60 min/day interval exercise, energy-matched with extra shake). 2-week intervention. OGTT with ghrelin, PYY, des-ghrelin at 0/30/60 min; VAS appetite scales.
Who was studied
26 women with obesity (BMI 37.3, age ~47 years)
What this study cannot tell us
Small sample (26 women); only 2 weeks — long-term effects unknown; women only; energy matching with post-exercise shake may not reflect real-world behavior; statistical significance borderline for some outcomes.
How to read the evidence
Moderate — randomized controlled trial but small (n=26), short duration (2 weeks), and borderline statistical significance.
When this study was published
Published in 2020; exercise-appetite interaction research has continued to expand.
The bigger picture
Exercise is often dismissed as unimportant for weight loss because "you can't outrun your diet." This study shows exercise's value isn't just calories burned — it reprograms appetite hormones to make dieting easier.
Questions still open
- Does the ghrelin-suppressing effect persist beyond 2 weeks?
- Would lower-intensity exercise have a similar effect on ghrelin?
- Does this apply equally to men or to different BMI ranges?
Common questions
Why does interval exercise reduce hunger?
How intense does the exercise need to be?
Read the original research
Short-term interval exercise suppresses acylated ghrelin and hunger during caloric restriction in women with obesity.
Physiology & behavior, 223, 112978
Citation
Malin, Steven K; Heiston, Emily M; Gilbertson, Nicole M; Eichner, Natalie Z M. (2020). Short-term interval exercise suppresses acylated ghrelin and hunger during caloric restriction in women with obesity.. Physiology & behavior, 223, 112978. https://doi.org/10.1016/j.physbeh.2020.112978