100km Weeks and Less Lifting: What Elite 15 HYROX Athletes Do Differently
Most age-group HYROX athletes spend their training week trying to balance the barbell and the track in roughly equal measure. Lift heavy, run enough, repeat. It feels logical. It mirrors the sport's identity as a hybrid discipline. But when you look closely at how Elite 15 athlete Louis Osselaer actually trains, that assumption falls apart quickly.
Osselaer has pushed his weekly running volume toward 100 kilometers. He's pulled back significantly on traditional strength work. And he's built deliberate mental recovery into his season in a way most competitive athletes would consider soft. The results suggest he's onto something.
Why 100km Running Weeks Change the Equation
Running accounts for roughly half of total HYROX race time for most competitors. In the Elite field, where athletes are finishing under an hour, the aerobic engine becomes even more decisive. A few seconds per kilometer across the eight 1km running splits adds up fast when the fitness gap between athletes is already razor thin.
Osselaer's approach reflects a deliberate prioritization: if running is the discipline with the greatest time return, it deserves the greatest training investment. Reaching 100km weeks isn't casual mileage accumulation. It requires structured base-building phases, disciplined pacing on easy days, and the kind of aerobic adaptations that take months to express. The process isn't unlike what serious marathon runners use to build their aerobic foundation, as detailed in this guide on base-building for fall marathon preparation.
For context, most competitive age-group HYROX athletes run 30 to 50km per week. Doubling that volume changes your physiology. Mitochondrial density increases. Lactate threshold rises. Your legs become more efficient at clearing fatigue between efforts, which matters enormously when you step off the ski erg and immediately need to run a kilometer at pace.
The practical challenge is that this volume demands careful management. Running-related injury risk scales with rapid mileage increases. Osselaer's approach isn't about jumping to 100km immediately. It's about building toward it progressively while protecting recovery capacity.
The Counterintuitive Decision to Cut Strength Work
Here's where Osselaer's training philosophy becomes genuinely uncomfortable for the hybrid athlete community. He has significantly reduced traditional barbell strength training. No heavy squats, no conventional deadlift cycles, not the kind of lower-body loading most HYROX coaches would consider non-negotiable.
The reasoning is grounded in specificity. Heavy compound lifts build strength, but they also generate substantial muscular fatigue and require meaningful recovery time. When your weekly running volume is high, that recovery capacity is already under pressure. Prioritizing barbell work means either reducing running quality or accumulating fatigue that compromises both.
There's also the question of transfer. Absolute strength in a back squat doesn't map directly onto HYROX performance the way that many athletes assume. The stations require strength endurance, the ability to sustain force output under aerobic fatigue, not maximal force production in a fresh state. For athletes already carrying adequate base strength, additional barbell volume may produce diminishing returns.
This doesn't mean Osselaer trains without any strength work. It means he's selective about what he keeps and strategic about what he removes.
Walking Lunges as a Functional Replacement
What fills the gap left by reduced barbell training? High-volume walking lunges. And the specificity here is significant.
Walking lunges develop single-leg strength, hip stability, and the ability to sustain lower-body output under fatigue. Those qualities transfer directly to the sled push and sled pull. Both stations require you to drive through one leg at a time, leaning into load, maintaining posture while your aerobic system is already stressed. A heavy barbell squat doesn't replicate that movement pattern. High-rep walking lunges do.
There's also an endurance component. Doing sets of 50 to 100 lunges per leg isn't the same training stimulus as three sets of five squats at 85% of your max. You're training the muscle's capacity to repeat contractions under sustained effort, which is exactly what race day demands across multiple stations.
The practical implication for age-group athletes is straightforward. If you're limited in training time, substituting barbell lower-body sessions with high-volume lunges might actually deliver better HYROX-specific outcomes while reducing the recovery load that competes with your running.
Sled Pull Technique as a Race-Day Differentiator
At the elite level, fitness differences between the top athletes are genuinely small. Everyone in Elite 15 is fit. The separators are technical and tactical.
Osselaer identifies sled pull technique and pacing as a specific area where athletes consistently leave time on the track. The sled pull is unique among HYROX stations because it demands full-body coordination under significant load while your cardiovascular system is already working hard. Athletes who haven't practiced the movement pattern under fatigue tend to degrade dramatically in form, which kills efficiency and burns unnecessary energy.
The technical cues that matter: hip hinge position, rope hand placement, step timing, and the rhythm of pull-and-step cycles. These are trainable, but they need to be practiced in a fatigued state to actually transfer to race day. Doing sled pull work when you're fresh builds technique. Doing it after a hard run or ski erg effort builds race-specific proficiency.
Pacing matters too. Starting the sled pull too aggressively spikes heart rate into a zone that costs you on the subsequent run. Osselaer's approach involves controlled early effort and consistent tempo rather than maximal output from the first step. That pacing discipline is something most age-group athletes need to develop deliberately, not assume they'll figure out on race day.
What Mental Recovery Actually Looks Like in Practice
A long HYROX competitive season runs from September through late spring. For athletes competing seriously across multiple events, that's seven to eight months of structured training, racing, and recovery management. The psychological load is substantial.
Osselaer builds genuine breaks from structured training into his plan. Not deload weeks with reduced intensity, but actual periods where training becomes unstructured or recreational. The purpose isn't just physical recovery. It's resetting motivation, reducing the mental fatigue of constant structured effort, and returning to training with genuine drive rather than grinding obligation.
Research in endurance athletes consistently shows that psychological fatigue impacts performance independently of physical fatigue. An athlete who is mentally depleted makes worse pacing decisions, tolerates discomfort less effectively, and is more likely to abandon effort during hard segments. Managing mental freshness is part of performance optimization, not separate from it.
Nutrition also plays a role in sustaining a long season. Athletes under high training loads need to be intentional about fueling, not just around workouts but across the full day. If you're uncertain about what's actually evidence-based in sports nutrition, this breakdown of gels, bars, and whey products is worth your time. And for athletes managing high running volumes in particular, the hydration question matters more than most people account for, as explored in this look at pre-workout hydration strategies.
What Age-Group Athletes Can Actually Apply
Most people reading this aren't competing at Elite 15. But Osselaer's approach contains specific, actionable principles that translate across competitive levels.
- Audit your running-to-lifting ratio. If you're running 30km per week and lifting four days, the balance may not be serving your HYROX performance. Running volume has a higher ceiling for time gains in race conditions than most athletes realize.
- Replace some barbell lower-body work with walking lunges. Even substituting one session per week builds station-specific endurance without the same recovery cost as heavy compound work.
- Practice sled pull under fatigue. Stop treating it as a technical drill done fresh. Build it into workouts after cardiovascular work to develop race-day specificity.
- Build pacing plans for high-demand stations. Know your target effort level for the sled pull and stick to it regardless of how good you feel early in the race.
- Schedule real mental breaks. Two weeks of unstructured activity twice per season won't wreck your fitness. It may protect your motivation across the full competitive calendar.
Building aerobic capacity at this level also has a significant VO2 max component. If you want to understand the physiology behind high-volume running adaptations, this evidence-based guide on improving VO2 max provides a clear framework.
The Bigger Lesson
HYROX rewards athletes who train specifically for HYROX. That sounds obvious, but the execution is less intuitive than it appears. Equal parts lifting and cardio sounds balanced, but it may not be optimal. High running volume with targeted functional strength work and deliberate recovery management is the approach that's producing results at the sharp end of the sport.
Osselaer's training isn't a template to copy wholesale. It's a signal about where the performance leverage actually is. More running, smarter strength selection, and the discipline to rest intentionally. Those are principles you can apply at any competitive level, and the athletes who figure that out early tend to be the ones who keep improving while others plateau.