Rapid weight loss negatively effects salivary IgA before competition in elite powerlifters

Abstract

Problem Statement: Little is known about whether rapid weight loss (RWL) through fluid manipulation influences markers of hydration, body compartment water and salivary immune response before or after a full powerlifting competition when compared to competitors that did not use any methods of weight reduction. Purpose: The purpose of this study was to determine if RWL before competition negatively impacted markers of hydration and salivary immune function and whether those markers were altered by competition compared to those that did not undergo RWL. Approach: On the day of competition 21 (14 male, 7 female) participants underwent anthropometry for intra-cellular (ICW), extra-cellular (ECW), and total body water (TBW) and then provided urine and saliva samples immediately prior to completing a full powerlifting competition of squat, bench press, and dead lift. Urine was used to measure urine specific gravity (USG) and saliva was used to determine salivary immunoglobulin A (sIgA). Measures were repeated following competition. Participants were analyzed as non-body weight manipulation (HH,-0.41±0.17 % body mass, n=8) or RWL fluid manipulation (DH,-3.32±0.76% body mass, n=13) with significance being set at p ≤ 0.05. Results: There was a significant difference in the amount of body mass lost between participants in DH (reduced body mass by 3.1-4.7% [1.74-4.36kg] over a 3-day period) compared to HH (<0.5% [≤0.51kgs]) over the same time (p<0.001). There were no differences between groups in USG at either time point. DH presented with significantly lower sIgA (p=0.003), ICW (p=0.004), and TBW (p=0.009) compared to HH. Both groups significantly increased sIgA (p=0.042), ICW (p<0.001), and TBW (p=0.001) pre-to-post-competition with DH having significantly higher increases in ICW (p=0.008) and TBW (p=0.018) compared to HH. sIgA (p=0.020) and ICW (p=0.039) differences were maintained post competition with DH having significantly lower values. Both groups significantly increased sIgA secretion rate pre-to post-competition (p=0.018) but with no difference between groups at either time point. Conclusions: RWL appears to suppress sIgA and cause compartment loss of water in elite powerlifters. Competitors presenting with indicators of body and compartmental dehydration increased hydration levels over the course of a full competition with ad libitum consumption but should be cautious of inducing serious dehydration which has negative health and performance implications.