Why Runners, Walkers, and Hyrox Athletes Still Need Heavy Strength Training

Oct 19

Hyrox is a fitness race that has taken off over the last few years. You run 1 kilometer, then do a station like pushing a heavy sled, rowing, carrying weights, or throwing a ball at a wall. Then you run another kilometer and do another station, eight rounds in total. Recreational athletes in one study finished in about 86 minutes.

If you've never heard of it, stay with me. The question underneath it applies to anyone whose routine leans on one kind of exercise: runners, walkers, people who live on the bike or the elliptical.

Right now a lot of Hyrox training is mostly running plus lighter, faster circuits, with heavy lifting dropped from the plan. The reasoning is easy to follow: the race is mostly running, and the stations don't require lifting anything near your max. I think that reasoning misses a few things, and the research gives us reasons to keep heavy strength training in the mix.

What does Hyrox actually demand?

In the first physiology study of a simulated race, the running took about 51 of the 86.5 minutes. The authors described the sport as endurance-focused, with moderate-to-low demands for maximum strength. Faster finishers had a higher VO2max (a measure of aerobic fitness), more endurance training volume, and lower body fat (Brandt et al., 2025).

An analysis of nearly 40,000 results from the sport's top divisions found the same thing: running made up about half of total race time, and the strength-based stations contributed meaningfully too (Rappelt et al., 2026). Even elite men ran the course at a submaximal pace on average, about 76% of their maximal aerobic speed (Gutiérrez-Hellín et al., 2026).

So Hyrox is an endurance event with a strength-endurance piece built in. It does not reward maximal strength or sprint speed the way a powerlifting meet or a track meet does. That explains why people train it the way they do, and it also means the plan can leave those qualities undeveloped.

Does heavy lifting help runners?

Several meta-analyses say it does, with limits. In middle- and long-distance runners, strength training with heavy loads (80% of one-rep max or more) produced a small improvement in running economy, which is how much energy it costs you to run at a given pace. It also produced a moderate improvement in performance measures like time trials and time to exhaustion (Llanos-Lagos et al., 2024a, 2024b). A separate meta-analysis found heavy lifting outperformed jump training for running economy, loads near 90% of one-rep max did better than lighter loads, and programs lasting 10 to 14 weeks did better than programs lasting 6 to 8 (Eihara et al., 2022).

The trial I find most relevant to Hyrox gave 28 well-trained male runners either their usual running alone or running plus two heavy strength and jump sessions a week for ten weeks. After 90 minutes of running, the strength group had better running economy than the running-only group (about 2% better versus 0.6% worse). In a hard effort to exhaustion at the end of that run, the strength group improved by 35% from their own baseline and the running-only group got 8% worse (Zanini et al., 2025).

Compare that with the race data. Elite men slowed from about 16.1 km/h on the first run to 13.6 km/h on the eighth. Holding pace and efficiency while tired matters a lot in an event like this. The trial and the race data come from different groups and different tests, so treat the connection as a reasonable hypothesis and not a proven result.

There are limits. Heavy lifting did not change VO2max or sprint capacity in the meta-analysis. In a small trial of middle-aged recreational runners, ten weeks of resistance training improved running economy by about 2% but did not change 5K time (Eihara et al., 2024). Heavy strength work helps, and it works alongside the running, not in place of it.

What about cramping and muscle damage?

A 2026 study followed 58 people who finished an ultra-trail race, 9 of whom developed cramps. Body weight loss, urine concentration, and blood sodium did not differ between the crampers and everyone else. What did differ was muscle damage: the crampers had much higher creatine kinase (a marker of muscle breakdown) 24 and 48 hours later. Only 56% of the crampers did regular lower-body strength training, compared with 88% of the runners who didn't cramp (Martinez-Navarro et al., 2026).

That is a small observational study of a different sport, so it can't show that lifting prevents cramps. It does suggest that for long, repetitive efforts, how well your muscles tolerate damage may matter as much as how much salt you took in.

What does this have to do with walking?

Gait speed is how fast you walk at a comfortable pace. It's one of the better simple predictors of how long older adults will live. A pooled analysis of nine studies and 34,485 adults aged 65 and older found that each 0.1 meter per second of faster walking was associated with about 12% lower risk of dying during follow-up (Studenski et al., 2011).

Walking is great for your heart and for staying active. The question is what makes you able to walk faster, and strength is part of the answer. A meta-analysis of 24 resistance training studies in healthy adults over 65 found it increased gait speed by about 0.11 meters per second on average (Hortobágyi et al., 2015). Those results were similar to what balance-focused and mixed programs produced, so lifting isn't the only route. It is a reliable one.

You don't need a lot of it. A review of 151 trials in adults over 60 found that even low-volume programs improved physical function (timed up-and-go and 6-minute walk distance) and added lean mass (Radaelli et al., 2024).

The bigger picture

An umbrella review of meta-analyses found that people who did both aerobic and resistance training had about 40% lower all-cause mortality than those who did neither (equivalent hazard ratio 0.60), and resistance training alone was linked to about 18% lower cardiovascular mortality (0.82). These are observational findings that the authors rated as suggestive, not convincing, but the direction is consistent: the combination looked better than either one alone (Rahmati et al., 2025).

What I'd recommend

If you're training for Hyrox or a running race: keep the running and the race-specific work, and keep a couple of heavy lower-body sessions each week. The studies that showed benefits used heavy loads (80% to 90% or more of your max) for 10 weeks or longer. That is the dose studied in the research, so adjust it to your experience and history.
If your routine is mostly walking, cycling, or other cardio: add some strength work. Two sessions a week of squats, hinges, and lunges or step-ups, pushing toward challenging loads over time, covers the base.
If you've been told to skip lifting to save energy for your sport: consider keeping one or two sessions anyway. Strength is the quality that tends to fade first when it isn't trained.
Give it time. The longer programs in the research outperformed the shorter ones, so think in months.
Include your calves. In the middle-aged runner trial, bigger gains in calf-raise strength went along with better running economy.

Whatever you're training for, the heavy work supports it: faster running late in the race, a more durable body, and a faster walk decades from now.

Sources

Brandt T, et al. Acute physiological responses and performance determinants in Hyrox. Front Physiol. 2025. https://doi.org/10.3389/fphys.2025.1519240
Rappelt L, et al. Longitudinal performance development in PRO and ELITE HYROX competitions across the first seven competitive seasons. Front Physiol. 2026. https://doi.org/10.3389/fphys.2026.1847569
Gutiérrez-Hellín J, et al. Relative running intensity and pacing during an official HYROX PRO MEN competition: the HYScience Study. Int J Sports Physiol Perform. 2026. https://doi.org/10.1123/ijspp.2026-0098
Llanos-Lagos C, et al. Effect of strength training programs in middle- and long-distance runners' economy at different running speeds. Sports Med. 2024;54(4):895-932. https://doi.org/10.1007/s40279-023-01978-y
Llanos-Lagos C, et al. The effect of strength training methods on middle-distance and long-distance runners' athletic performance. Sports Med. 2024;54(7):1801-1833. https://doi.org/10.1007/s40279-024-02018-z
Eihara Y, et al. Heavy resistance training versus plyometric training for improving running economy and running time trial performance. Sports Med Open. 2022;8(1):138. https://doi.org/10.1186/s40798-022-00511-1
Zanini M, et al. Strength training improves running economy durability and fatigued high-intensity performance in well-trained male runners. Med Sci Sports Exerc. 2025;57(7):1546-1558. https://doi.org/10.1249/MSS.0000000000003685
Eihara Y, et al. The effects of plyometric versus resistance training on running economy and 5-km running time in middle-aged recreational runners. Eur J Sport Sci. 2024;24(12):1820-1829. https://doi.org/10.1002/ejsc.12197
Martinez-Navarro I, et al. Muscle cramping in ultra-trail: dehydration and electrolyte depletion versus muscle damage. J Strength Cond Res. 2026;40(8):e894-e900. https://doi.org/10.1519/JSC.0000000000005440
Studenski S, et al. Gait speed and survival in older adults. JAMA. 2011;305(1):50-58. https://doi.org/10.1001/jama.2010.1923
Hortobágyi T, et al. Effects of three types of exercise interventions on healthy old adults' gait speed: a systematic review and meta-analysis. Sports Med. 2015;45(12):1627-1643. https://doi.org/10.1007/s40279-015-0371-2
Radaelli R, et al. Effects of resistance training volume on physical function, lean body mass and lower-body muscle hypertrophy and strength in older adults: a systematic review and network meta-analysis of 151 randomised trials. Sports Med. 2025;55(1):167-192. https://doi.org/10.1007/s40279-024-02123-z
Rahmati M, et al. Associations between exercise training, physical activity, sedentary behaviour and mortality: an umbrella review of meta-analyses. J Cachexia Sarcopenia Muscle. 2025;16(2):e13772. https://doi.org/10.1002/jcsm.13772

Jacob Salaba