Rapid Weight Loss Across Combat Sports and the Relationships Between Methods and Magnitude

The medical question

Which weight-cutting methods go with the largest weight cuts, and in which combat sports are the cuts largest?

The Fight Medicine Research Institute uses this evidence to frame questions about how fighters make weight and which methods accompany the largest weight cuts. The study’s self-reported survey data and uneven numbers per sport determine which questions it can inform.

Summary

In a survey of 256 combat sports competitors, larger weight cuts were associated with more use of fluid restriction, water loading and sauna, and Muay Thai, kickboxing and MMA athletes reported larger cuts than athletes in several other combat sports.

What the work reports

• 256 combat sports competitors completed an online survey, which the article dates to August to December 2019, about how much weight they usually lose before competition, when they lose it and which methods they use. Most lived in the United States, Australia, the United Kingdom or Canada.
• Respondents typically lost 5.16 kg before a competition (3.64 kg in the 2 weeks before and 1.64 kg in the 24 hours before) and regained 2.47 kg after the weigh-in. Athletes in Muay Thai or kickboxing and in MMA reported larger typical losses than those in Brazilian jiu-jitsu and judo. More use of fluid restriction, water loading and sauna was associated with greater weight loss in the 2 weeks and the 24 hours before the weigh-in, and 50 respondents reported having used laxatives, 48 diuretics, 34 diet pills and 30 vomiting.
• The authors conclude that larger weight cuts were associated with more use of fluid-manipulation methods, and that the use of higher-risk methods was in many cases associated with starting rapid weight loss at a younger age.

Limits to keep in mind

• Cross-sectional survey: it shows associations between methods and the amount of weight lost and cannot show cause.
• All data were self-reported. The authors note that accuracy may be affected by the athletes’ memory and motivation.
• Respondents were recruited through gyms, organisations and online message boards, and the numbers per sport and competitive level were uneven. The authors state that they could not analyse some findings by sport or level.

Source issues recorded

• The abstract says athletes engaged in rapid weight loss on average three times a year. The survey item was a rating of how often they had lost weight before competition in the previous 2 years, from 1 (never) to 5 (every time), with a mean of 3.73 in Table 3.
• The abstract says that use of certain high-risk methods was associated with an increased likelihood of disordered eating behaviours. The article reports no measure of disordered eating; its Discussion raises it as a possibility.
• Crossref lists the publisher’s text and data mining licence alongside the Creative Commons Attribution 4.0 licence for the version of record.

Publication status and notices

Published in Translational Sports Medicine, a peer-reviewed journal. Original research article in Translational Sports Medicine.

Form of this work: Version of record. The version of record is the final article as issued by its publisher.

No correction or retraction notice was found in Crossref or Europe PMC when this record was checked.

Fight Medicine Research Institute contribution

Fight Medicine Research Institute selected and catalogued this study, prepared an original research summary, verified its bibliographic details, and maintains the associated citation record.

PDF files

Article details

Relationship

External research catalogued by the Fight Medicine Research Institute. The original authors, journal and DOI are unchanged.

Published online

26 March 2025

Issue date

January 2025, volume 2025, issue 1

Repository date

26 March 2025 (Europe PMC first-publication date)

Date used here

26 March 2025 (Crossref publisher deposit, online publication date)

Rights

CC BY 4.0. Open access under a Creative Commons Attribution licence (CC BY 4.0), as recorded by Europe PMC and the licence link in the source record. The summary on this page is Fight Medicine Research Institute’s own wording. No text or figure from the article is reproduced here. Licence terms.

Source check

12 November 2026, against PubMed Central full text, Crossref and Europe PMC. Checked under the direction of Casey C. Sears, Founder. An LLM was utilized as a research tool with direct human oversight.

Appraisal

The check covered bibliographic details, links, licence and notices. It is not a formal critical appraisal of the full paper.

Clinical review

None. This record is a research summary, not clinical education.

Funding and conflicts

The article states no funding and no competing interests.

Catalog

FH-056, added 12 November 2026

Cite the original work

These files cite the work by its own authors, journal and DOI. Fight Medicine Research Institute appears only in a note, as curator of this catalog page.

Oliver R Barley, Craig A Harms. Rapid Weight Loss Across Combat Sports and the Relationships Between Methods and Magnitude. Translational Sports Medicine. 2025;2025(1):2946317. https://doi.org/10.1155/tsm2/2946317

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