After six weeks of intense exercise and reduced calorie intake, female rats show a 31% drop in progesterone, suggesting that short-term energy deficits can suppress hormone production linked to reproductive cycles.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether endurance exercise with energy restriction consistently suppresses progesterone in female mammals during the early phase of training, and whether this effect is reversible with energy repletion.
A systematic review and meta-analysis of all controlled studies in female mammals comparing endurance exercise with energy restriction (≤80% of baseline intake) to sedentary controls, measuring serum progesterone at week 6 as a primary outcome.
Whether 6 weeks of treadmill training with energy restriction causes a 31% reduction in serum progesterone in female rats compared to sedentary controls.
A double-blind, randomized controlled trial in 60 female Sprague Dawley rats, randomized to either 6 weeks of treadmill training (40 min/day, 6 days/week) with energy intake restricted to 79% of baseline or sedentary controls with ad libitum feeding, measuring serum progesterone via ELISA at week 6 as the primary endpoint.
Whether female rats with greater energy deficits during early training show progressively lower progesterone levels over time.
A prospective cohort study following 100 female Sprague Dawley rats undergoing varying levels of treadmill training (0–60 min/day) with energy intake restricted to 70–90% of baseline, measuring serum progesterone weekly for 6 weeks.
Whether rats with the lowest progesterone at week 6 are more likely to have experienced greater energy restriction than those with higher levels.
A case-control study comparing 30 rats with the lowest progesterone (<1.0 ng/mL) to 30 with the highest (>2.0 ng/mL) at week 6, retrospectively analyzing their daily energy intake and exercise volume, matched for baseline weight.
Whether there is an inverse association between energy intake and serum progesterone in female rats at week 6 of endurance training.
A cross-sectional analysis of 120 female Sprague Dawley rats at week 6 of treadmill training with energy restriction, measuring daily energy intake and serum progesterone simultaneously, adjusting for body weight and training volume.