First peer-reviewed HYROX study published Aug. 23

A peer-reviewed HYROX paper was published on March 31, 2025 in *Frontiers in Physiology*, according to the journal record, and it described itself as the first scientific study on HYROX. Keedia reported this week that the study is now being treated by coaches and athletes as a benchmark for sport-specific preparation, after years in which HYROX competitors borrowed training ideas from triathlon, CrossFit and marathon programs. The paper, led by Tom Brandt of the University of the Bundeswehr Munich, examined acute physiological responses and performance determinants during a simulated HYROX competition. (pmc.ncbi.nlm.nih.gov) The abstract said 11 recreational athletes took part, with median HYROX experience of 18 months, and researchers measured heart rate, blood lactate, rating of perceived exertion, hand-grip strength and VO2 max. ### So was there really a “first peer-reviewed HYROX study” on August 23, 2026? (keedia.com) The journal record points to an earlier date. *Frontiers in Physiology* lists “Acute physiological responses and performance determinants in Hyrox” as published on March 31, 2025, not August 23, 2026. August 23, 2026 appears to be the date cited in secondary coverage summarized by keedia, not the primary journal publication date visible in the paper record surfaced through PubMed Central. (pmc.ncbi.nlm.nih.gov) Keedia wrote that August 23, 2026 was when the “first peer-reviewed study dedicated specifically to HYROX training was published,” but the primary source available online shows the article in 2025. ### What did the study actually test? The study used a simulated “Individual Open Division” HYROX race format after a 48-hour rest period, the abstract said. Researchers tracked heart rate throughout the event and recorded blood lactate and perceived exertion before and after each run and station. The paper reported a median completion time of 86.5 minutes. Runs accounted for 51.2 minutes and exercise stations 32.8 minutes, a split that keedia said has fed debate over whether athletes should treat HYROX more like an endurance event than a pure strength competition. (keedia.com) That interpretation is keedia’s, not language used in the journal abstract. ### Why were triathlon, CrossFit and marathon training mentioned? (pmc.ncbi.nlm.nih.gov) Keedia said HYROX athletes had long built programs from “borrowed logic” — triathlon periodization, CrossFit conditioning blocks and marathon pacing frameworks — because sport-specific evidence was limited. The journal abstract itself does not use that exact comparison language in the lines available through PubMed Central. (pmc.ncbi.nlm.nih.gov) It says the study aimed to assess physiological responses and possible performance determinants in order to derive training recommendations and practical applications. ### Who conducted the research, and how big was it? Tom Brandt, Cindy Ebel, Christopher Lebahn and Annette Schmidt were listed as authors, all affiliated with the Institute of Sports Science at the University of the Bundeswehr Munich. (keedia.com) The sample was small — 11 recreational athletes, 27% women — which means the findings describe an early evidence base rather than a large population study. That said, the paper is part of a broader run of HYROX-related academic work now appearing in 2026, including studies on participation trends, injury burden and elite competition development. (pmc.ncbi.nlm.nih.gov) ### What should readers take from the date discrepancy? The clearest verified takeaway is that a peer-reviewed HYROX study exists and that the primary paper available online is dated March 31, 2025. (pmc.ncbi.nlm.nih.gov) September 2026 coverage from keedia shows the study is newly circulating in consumer fitness media, and Hindustan Times has also been covering HYROX as the sport grows. But based on the primary source available, the “published Aug. 23, 2026” framing should be treated cautiously unless a separate August 23, 2026 journal item is identified. (frontiersin.org) (keedia.com) (pmc.ncbi.nlm.nih.gov)