To assess the influence of moderate, acute weight loss on on‐water rowing performance when aggressive nutritional recovery strategies were used in the two hours between weigh in and racing.
Competitive rowers (n = 17) undertook three on‐water 1800 m time trials under cool conditions (mean (SD) temperature 8.4 (2.0)°C), each separated by 48 hours. No weight limit was imposed for the first time trial—that is, unrestricted body mass (UNR1). However, one of the remaining two trials followed a 4% loss in body mass in the previous 24 hours (WT−4%). No weight limit was imposed for the other trial (UNR2). Aggressive nutritional recovery strategies (WT−4%, 2.3 g/kg carbohydrate, 34 mg/kg Na+, and 28.4 ml/kg fluid; UNR, ad libitum) were used in the first 90 minutes of the two hours between weigh in and performance trials.
WT−4% had only a small and statistically non‐significant effect on the on‐water time trial performance (mean 1.0 second, 95% confidence interval (CI) −0.9 to 2.8; p = 0.29) compared with UNR. This was despite a significant decrease in plasma volume at the time of weigh in for WT−4% compared with UNR (−9.2%, 95% CI −12.8% to −5.6%; p<0.001).
Acute weight loss of up to 4% over 24 hours, when combined with aggressive nutritional recovery strategies, can be undertaken with minimal impact on on‐water rowing performance, at least in cool conditions.