For 15 years, Matt Russell lived by a single, unshakeable dogma: if you want to get faster, you need a bigger aerobic engine.
As a professional triathlete who raced over 45 Ironmans, Russell’s life was defined by the relentless pursuit of cardiovascular endurance. Swimming, biking, and running formed his entire universe. Lifting weights? Completely counterproductive. Like generations of endurance athletes before him, Russell believed that muscle meant extra weight, and extra weight meant slower race times.
Then, he retired from pro racing in 2023—and discovered Hyrox.
Suddenly, the endurance veteran was forced to confront movements he had ignored for decades: heavy sled pushes, rowing, wall balls, and lunges. The reality check was humbling.
"I realized how weak my glutes and hamstrings actually were," Russell admits. "I could swim, bike, and run all day, but I really struggled with things like wall balls."
Russell isn't alone. A massive wave of former elite triathletes—including world champions and Olympic-tier competitors—are diving headfirst into Hyrox. But this isn't just a mid-retirement hobby. It’s a seismic shift in how elite athletes view the relationship between cardio and strength.
The Blind Spot of Pure Endurance
Hyrox is a rapidly exploding global sport that combines eight 1K runs with eight functional fitness stations. On paper, it looks nothing like the steady-state, outdoor grind of a triathlon. Yet, with 1.5 million global participants annually, it's becoming the ultimate playground for former endurance junkies.
According to physical therapist Dr. Josh Funk, founder of Rehab 2 Perform, the triathlon community suffers from a glaring blind spot.
"Typically, triathletes have huge aerobic engines and underbuilt everything else," Funk explains. "Eventually something gives because the load outruns the capacity built to handle it."
Decades of repetitive, single-plane movements create ticking time bombs in the human body. Overuse injuries—like Achilles tendinopathy, tibial stress fractures, and lower back pain—are practically a rite of passage for endurance athletes.
The harsh physiological truth? No amount of mileage protects against age-related muscle and bone loss. Past your mid-thirties, you lose muscle mass, bone density, and fast-twitch muscle fibers every single year.
Why Strength Is the Ultimate Longevity Hack
Heavy compound lifting isn't about looking bulky; it’s about raising your body's physical tolerance.
When you introduce multi-joint, functional movements into a cardio-heavy routine, you stiffen tendons, improve bone density, and preserve tissue capacity. In short: it turns your weekly training load into a fraction of what your body is actually capable of handling.
For 52-year-old Hyrox world record holder Amy Bevilacqua, adding functional strength to her endurance background completely changed the game.
After years of competitive road cycling and triathlon—and surviving a tear in both proximal hamstrings—she transitioned to Hyrox. Last year, when life forced her to drop gym access and lean exclusively on running, she didn't break down like she used to. Instead, she jumped into a half-marathon on a whim and ran dangerously close to her personal record—completely untrained for the distance.
“I attribute that directly to all of the functional strength work I’ve done for so long,” Bevilacqua says.
How to Train Like a Hybrid Athlete
You don't need to throw away your running shoes or abandon the pool to reap the benefits of this movement. The secret is striking a balance: keep your aerobic engine-building, but sprinkle in targeted functional strength.
If you're an endurance athlete looking to bulletproof your body, Dr. Funk recommends incorporating these four game-changing exercises:
- Sled Pushes: Builds serious lower-body power with virtually zero eccentric load, meaning you get strong without trashing your legs for your weekly run.
- Weighted Lunges: Exposes left-right muscular asymmetries that cyclical sports like running let you hide for years.
- Farmer’s Carries: Teaches your core and trunk to hold a rigid, safe position under heavy loads and extreme fatigue.
- Rowing: Lights up the posterior chain (glutes, hamstrings, back) that endurance athletes often let go dormant.
The Bottom Line
For athletes like Matt Russell—who has packed on 15 pounds of pure muscle while maintaining his speed and qualifying for the Hyrox World Championships—the takeaway is crystal clear.
You don't have to stop being an endurance athlete. You just have to become a stronger one.
