Short term body mass manipulation in powerlifting: a narrative review and best practice recommendations

Short Term Body Mass Manipulation (SBM) is frequently used in powerlifting by athletes to qualify for lower weight classes and improve relative competitiveness. The three primary physiological pathways that SBM leverages are gastrointestinal content reduction, glycogen storage and body water manipulation, in addition to post-weigh-in refueling. Despite its high prevalence among athletes competing in the International Powerlifting Federation (IPF), the scientific literature on SBM remains limited, and sport-specific guidelines are currently lacking. This narrative review summarizes the current evidence on SBM in powerlifting, with a focus on physiological mechanisms, practical implementation, and associated risks. The specific demands of IPF competition, consisting of maximal strength performance after only a two-hour window between weigh-in and competition, necessitate uniquely tailored SBM strategies. SBM should not be regarded as a standard preparation method. Instead, it should be seen as a targeted intervention to be applied with caution and strategic intent. The decision to implement SBM must be based on individual assessment, physiological plausibility, and a well-considered cost-benefit rationale. Ensuring effective rehydration and refueling between weigh-in and competition is critical to support both safety and performance. This review provides sport specific, evidence-based recommendations to assist practitioners in applying SBM responsibly within the context of powerlifting.