For years, Blood Flow Restriction (BFR) training has been a popular weapon for elite athletes, most recently popularised by Manchester City Women's Football Club and Cameron Norrie, British Tennis star and committed cyclist. Now, thanks to Hytro’s integrated wearables, it’s gaining traction with cyclists. We sat down with Team GB Track phenomenon Joe Truman and Hytro’s Chief Scientific Officer, Dr Tom Brownlee, to find out if ‘strapping in’ is the ultimate hack for faster hills and fresher legs.
Joe, you’ve been a powerhouse of British track cycling for years. How long has BFR been in your toolkit?
Joe Truman: I’ve been using BFR since about 2018. Early on, it was purely a rehab tool. I’d had a back injury and couldn't load up a barbell in the gym, but BFR allowed me to stress my quads and hamstrings intensely without needing that heavy external weight. Since partnering with Hytro, it’s evolved. It’s no longer just for the gym; I use it for recovery and even specific work on the bike.
The hypoxic (low oxygen) environment created by BFR, enables your muscles to get stronger and recover faster despite the low load.
For the uninitiated, what is the actual process? It sounds like you’re just cutting off circulation.
Dr Tom Brownlee: It’s important to clarify that we aren't fully cutting off blood flow—we call it ‘sub-occlusive’ pressure. By tightening the straps, integrated into a pair of Hytro shorts or T-shirt, we allow blood into the muscle via the arteries but restrict it from leaving through the veins. This creates a hypoxic (low oxygen) environment and a buildup of metabolites like lactate. With BFR, your muscles get stronger and recover faster than they would without it.
Joe Truman: In simple terms, it pre-stresses the muscle. It tricks your body into thinking it’s working much harder than it is. On the bike, it gets you into that red zone faster and more efficiently.
It lets you get more bang for your buck in shorter sessions...
Joe Truman
Many of our readers are more focused on endurance rather than 10-second max-effort sprints. Is there a benefit for the Sunday club run rider?
Dr Tom Brownlee: Absolutely. While sprinters love the power gains, BFR actually increases capillary density. This means your body becomes better at delivering oxygen to the muscles and, crucially, flushing out the waste products you don’t want. We also see increased mitochondrial enzyme activity, which is the holy grail for aerobic efficiency.
Joe Truman: It’s also a brilliant ‘plateau breaker’. If you’re stuck doing three hours of Zone 2 on the turbo every winter, BFR offers a new stimulus. It lets you get more bang for your buck in shorter sessions, which is a lifesaver if you’re balancing training with a full-time job or family commitments.
Hytro has simplified the often cumbersome nature of BFR. The straps are easy to adjust and always in the optimum position.
You mentioned recovery – how does pre-stressing the muscles enhance recovery? It seems counterintuitive.
Dr Tom Brownlee: It’s a two-stage process. First, the ‘swell’ triggers cells to recognize tension, which upregulates recovery signals. Then, when you release the straps, you get a massive ‘flush’ of fresh, oxygenated blood that clears metabolic byproducts. We’ve even seen evidence that this flush helps your muscles take up carbohydrates more quickly if you’ve had a recovery drink.
Joe Truman: For me, it’s about passive recovery. I can sit in front of the TV, strap into my Hytro shorts for a set protocol, and know I’m actively clearing out the biomarkers from a hard session. There’s very little ‘friction’ to it—you just put them on and reap the benefits.
Does it only target the muscles directly under or below the strap? What about the glutes?
Joe Truman: Anecdotally, the quads are where I feel the burn most as a cyclist. However, I use it for ‘pre-exhaustion’. If I do a set of leg extensions with straps on, my quads are already fatigued before I even start squats. That forces my glutes to work significantly harder to pick up the slack.
The beauty of BFR, the Hytro way, is that it can be used on rides, in the gym, during indoor bike efforts or while recovering on the sofa in front of the TV.
By their nature, those straps, or cuffs, are designed to be restrictive. Are the shorts comfortable to ride in?
Joe Truman: Unlike clinical BFR cuffs which are bulky and have wires, these are just like gym shorts. You can slip them over your cycling bibs on the turbo. I know riders who keep them in their back pocket during a road ride, strap in for a specific hill interval, and then loosen them for the descent.
Joe, you mentioned a clever ‘hack’ for riders who might be fitter than their ride buddies. How does that work?
Joe Truman: This is a great one for the social side of the sport. If you’re heading out with a group that’s a bit slower than your usual training pace, you can strap in. It increases the metabolic demand of the ride for you without you having to drop your friends or ride off the front. You get a high-intensity stimulus at a lower speed, so everyone stays together, but you still get your work in.
Finally, for the amateur racer who works a 9-to-5, how can they use this on race day?
Joe Truman: If you’re racing a Wednesday night crit after sitting at a desk all day, your body isn't primed. You can do a 15-minute BFR protocol at your desk in the morning. It triggers a hormonal response and gets the blood moving, so you show up to the start line feeling like you’ve already had a morning session, without the fatigue of actually riding.
Joe Truman is a champion sprinter, but Hytro is just as effective for endurance riders.
