Rapid weight gain in professional boxing and correlation with fight decisions: analysis from 71 title fights

ABSTRACT

Objectives: Boxing is a sport where athletes compete in several weight categories. Professional boxers typically dehydrate to cut their weight for the weigh-in (24 h before the contest) and then rehydrate before the fight. The International Boxing Federation (IBF) mandates a second weigh-in 12 h before the fight. Our objectives were: 1) To quantify the weight gain (WG) from the 1st to the 2nd weigh-in; 2) to investigate whether rapid WG affects boxing performance (win/loss rate) and 3) whether weight discrepancy (WD) 15 between boxers exposes them to increased health risks (rate of fights ended before time limit).

Methods: From official weigh-in reports of 71 IBF fights (142 fighters) the following data were gathered/calculated for each boxer: age, weight division, 1st weight, 2nd weight, WG between weigh-ins (kg and %), WD between opponents, and fight decision.

Results: Between the weigh-ins, the average WG was 2.52 ± 1.37 kg (range −0.3/6.4 kg) and 3.8 ± 2.2% of the initial body weight (range −0.4/9.3%) and the average WD 1.94 ± 1.50 kg (maximum 7.10 kg). Both WG and WD did not affect match outcomes. We observed tendencies for higher loss rate among boxers gaining more weight, and for higher victory rate in boxers with larger WD, however without reaching significance. A significant negative correlation was found between the 1st weight and the WG, both in absolute (r = −0.278, p = 0.001) and relative value (r = −0.497, p < 0.0001).

Conclusions: Although correlations between WG, WD and boxing performance were not found, single cases with an alarming high WG and WD were noted.

KEYWORDS:

• Combat sport
• martial art
• hydration
• traumatic brain injury
• concussion

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Erratum

Acknowledgments

We are indebted with Mr. Daryl J. Peoples, president of the International Boxing Federation (IBF)/United States Boxing Association and with all his staff for their availability and suggestions when discussing the topic of this research. Special thanks to Mr. Roberto Rea, European representative of IBF for collecting and supplying official weigh-in reports of IBF sanctioned fights.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Additional information

Funding

This article was not funded.