Effects of Rapid Weight Loss on Balance and Reaction Time in Elite Judo Athletes.

Balance, reaction time, and strength are key factors affecting judo performance. While ample research exists examining potential strength changes caused by weight loss prior to competition, changes in balance and reaction time, have been overlooked.

PURPOSE: The objective of this study was to examine the effects of rapid and progressive weight loss (RWL and PWL) on balance, reaction time, and strength in a group of elite judo athletes.

METHODS: 38 female and male judo athletes (age = 20.6 ± 2.6 years) completed balance, reaction time, and strength assessments one week prior to an official weigh-in (pre-test) and immediately after the weigh-in (post-test). The judo athletes were divided into three groups, one control group who maintained regular training and eating habits, one experimental group who engaged in PWL (<3% reductions in body mass) and a second experimental group who used RWL techniques (>3% reductions in body mass).

RESULTS: RWL group showed significant decreases (p<0.05) in balance performance (Ellipse area: 4.83±0.87 vs. 6.31±1.39 mm2 with eyes closed; Mean Mediolateral Velocity: 2.07±0.2 vs. 2.52±0.45 mms-1 with eyes closed; Mean Anteroposterior Velocity: 2.25±0.20 vs. 2.51±0.32 mms-1 with eyes open and 2.44±0.26 vs. 3.06±0.56 mms-1 with eyes closed) and reaction time (0.38±0.04 vs. 0.42±0.06 seconds) with no changes in strength from pre- to post-testing. The judo athletes in the progressive weight loss and control groups maintained performance in all variables.

CONCLUSION: These findings demonstrate negative effects on perceptual motor skill performance in judo athletes engaging in rapid weight loss strategies prior to competition.