Hyrox is mainly a hard aerobic running event rather than a strength test, and no study has tested whether Hyrox training improves triathlon performance
Interpretation
The only lab study (Brandt et al. 2025; 11 recreational athletes, 3 women) found running made up 51.2 of 86.5 minutes, most of the race was above 90% HRmax, and finishing time tracked VO2max (rho −0.71) and endurance training volume (rho −0.68), not resistance training volume or grip strength. A non-peer-reviewed 2026 narrative review found only 8 original Hyrox studies and reports running capacity as the strongest performance determinant in race-result data. Nothing tests transfer to triathlon; general cross-training evidence (Tanaka 1994; Millet et al. 2002, 4 elite triathletes) suggests transfer is partial, absent for swimming, and never exceeds sport-specific training. Schumann et al. (43 studies) show mixed strength-endurance training blunts explosive but not maximal strength gains.
Practical implication
Treat Hyrox as hard running-led cross-training or an off-season goal, not a substitute for swim, bike, run or heavy strength work, and allow recovery around races. The evidence is one small study plus a preprint, so this is inference, not tested advice.
Sources
5 sources, independently verified.
Simulated Individual Open Hyrox: total 86.5 min, runs 51.2 min vs stations 32.8 min; median 79.5% of time at 90–100% HRmax and 19.6% at 70–90%; peak lactate higher at stations (8.5 vs 7.7 mmol/L) and peak RPE higher (18 vs 16); wall balls hardest. Faster times correlated with higher VO2max (rho −0.71) and endurance training volume (rho −0.68), not resistance training volume (rho 0.34) or grip strength (rho 0.09). Limits: n = 11, treadmill runs, non-official sled, solo racing, only grip strength measured. Front Physiol 16:1519240.
Preprint posted July 2026, not peer-reviewed. Found 11 studies (8 original). Hyrox imposes sustained high metabolic and perceptual demands with high lactate at functional stations; running capacity consistently the strongest determinant of performance (including Rappelt et al. 2026, 39,696 race results, summarised by the review); injury, recovery and sleep under-investigated, with injury data only from a self-reported survey of 80 athletes (22 F, 58 M; 56.3% reported no injuries). Evidence mostly observational.
Concurrent vs strength-only training: maximal strength SMD −0.06 (95% CI −0.20 to 0.09, p=0.446), hypertrophy −0.01 (−0.16 to 0.18, p=0.919), explosive strength −0.28 (−0.48 to −0.08, p=0.007). Attenuation larger when both were in the same session (p=0.043) than when separated by ≥3 h (p>0.05). No moderation by cycling vs running, frequency (>5 vs <5 sessions/week), training status (untrained vs active) or age (<40 vs >40). Online 2021.
Some transfer of VO2max training effects exists from one mode to another, more noticeable when running is the cross-training mode; swim training may give minimal transfer; cross-training effects never exceed those of sport-specific training; cross-training may be a useful supplement during injury rehabilitation, overtraining or psychological fatigue. Abstract read on Springer; no numerical effect sizes in the abstract.
Systems-model analysis of 40 weeks of swim, bike and run training: training-performance relationships were significant for running (r = 0.74) and swimming (r = 0.37); cycling and running training transferred to each other (r = 0.56); swimming showed no transfer to or from cycling or running; running training had a major effect on competition performance (r = 0.52). Very small sample, modelling study.