Making weight makes sense: relative performance gains after rapid weight loss in powerlifting: a randomized controlled trial.

Background: Rapid weight loss (RWL) is a common strategy among competitive powerlifters aiming to qualify for lower weight categories and improve competitive advantage. However, the effects of RWL followed by short-term recovery on maximal strength performance remain unclear. This study aimed to examine whether a ~ 5% RWL protocol followed by a 2-hour recovery period affects changes in maximal and relative strength performance in trained male powerlifters.

Methods: This randomized controlled trial (RCT) was registered in the Australian New Zealand Clinical Trials Registry (ACTRN12622000924752). In this RCT study, 26 male powerlifters (24.6 ± 4.5 y; 92.8 ± 13.6 kg) were assigned to a rapid weight loss (RWL; n = 13) or control group (CON; n = 13). RWL participants followed a 4-day protocol including caloric restriction (-10%), low carbohydrate intake ( <50 g/day), low sodium, and fluid manipulation, targeting a 5% body mass reduction. The CON group maintained habitual diet and hydration. Maximal strength was assessed via simulated powerlifting competition conducted before (C1) and after (C2) the intervention. Performance variables included squat (SQ), bench press (BP), deadlift (DL), and total load (TOTAL), along with IPF GL (International Powerlifting Federation GoodLift points) and IPF GL BP (International Powerlifting Federation GoodLift for Bench Press) scores. Body composition and rate of perceived exertion (RPE) were also evaluated.

Results: The RWL group achieved a mean body mass reduction of 4.81%, with significant decreases in fat mass (-15.7%), fat-free mass (-2.36%), and body water (-2.41%) compared to CON (all p < 0.01). Despite these changes, no significant differences in maximal strength (SQ, BP, DL, TOTAL) were observed between C1 and C2 or between groups. However, the RWL group showed a significant post-intervention increase in IPF GL (p = 0.015) and IPF GL BP scores (p = 0.017). RPE values showed no consistent or practically relevant changes.

Conclusion: In the group that underwent a rapid weight loss of approximately 5%, followed by a short-term recovery period, maximal strength performance was maintained. This indicates that it is possible to reduce body mass without compromising absolute strength levels in competitive powerlifters. At the same time, RWL group achieved higher IPF GL and IPF GL BP values.