Zone 4 Madness! Can you fitness train on an E-Bike?!

Can you actually work out on an electric bike? That was the question I wanted to answer, and today I finally gave it a go. I haven’t owned an e-bike for six months because, honestly, I didn’t think I could train properly on one. This time I got hold of the new Specialized Levo 4, set it straight into Turbo mode for the whole ride, and decided to see if I could hold five solid minutes in Zone 4. If you know your heart rate zones, you’ll know that’s no easy task.

To make it harder, I picked a track with no easy sections. A techy climb, a techy descent, no flat in between. I strapped on a heart rate monitor, set my Garmin head unit to beep if I slipped out of the zone, and pointed the bike up the hill. My target was 163 beats per minute, and I was ready to go as hard as I could.

I was surprised how quickly I got into the zone. Within the first effort my heart rate jumped, and even though it dropped slightly on a descent, it didn’t take long to pull it back up again. The climbs were tough, the corners loose, and keeping momentum meant pushing harder than I expected. My legs were working, my lungs were burning, and for a moment I realised this was going to be more achievable than I thought.

It wasn’t easy. On one climb I failed and had to put a foot down, which cost me precious beats, and on some of the faster corners the bike felt like it wanted to leave the ground. But every mistake forced me to dig deeper. And that’s the difference with this kind of riding—there’s no coasting. You have to fully commit.

By the end of the block I was still in Zone 4, and it felt sustainable. That shocked me the most. I’d set a backup plan of staying in Zone 3 tempo if Zone 4 proved impossible, but I didn’t need it. The intensity of the terrain, the constant demand on both skill and effort, meant I stayed right where I wanted to be. It wasn’t just physical, it was mental too. Every section forced me to stay switched on.

When I caught my breath afterwards, I realised just how useful this could be for training. If you’re preparing for enduro racing, there’s nothing better. You’re climbing hard, then suddenly descending technical sections while already exhausted. On a normal bike you’d roll in tired, but on an e-bike you’re hitting those corners at speed, forced to handle the bike properly while your body is still screaming.

I went into the ride not even sure if I could get into Zone 4, and I came out knowing it’s not just possible but actually effective. Power numbers might spike all over the place, but for heart rate training, an e-bike works. It’s intense in every way—physically, mentally, skillfully. I didn’t expect that, and now I’m seriously thinking about getting an e-bike again, not just for fun, but for training too.

Want to know more about Ste's fitness journey or just having trouble sleeping, check out www.stesimms.com for more fascinating insights, thrilling graphs and exciting infographics!