Field Notes

Kilometre sixty, second climb. The sticker on your stem says 250 watts and your legs say 215. You did everything the plan told you. The plan was built on the wrong number.

2026-09-20 · 8 min read

Most apps show you a confident number from a model that has never met you. We built a more honest one — and then spent weeks trying to prove it wrong before it touched your screen. It mostly failed. So we didn't ship it, and that's the point.

2026-07-16 · 7 min read

Four on, four off, five times. Clean round numbers. The problem is your physiology has never once heard of four minutes — so we stopped counting reps and started reading the reserve.

2026-06-28 · 8 min read

Nail a personal best and most apps raise your FTP instantly. But the week you're flying is often the week your load is ramping hardest — and that's the worst moment to make every future target harder. So now and then, on purpose, we sit on the good news.

2026-06-24 · 4 min read

Two riders, the same FTP, completely different gifts — one wins the bunch kick, the other rides everyone off their wheel on the long climb. A single number can't tell them apart. The shape of their power curve tells them apart in a second.

2026-06-24 · 4 min read

Hour one, you hold 280 watts and chat. Hour three, the same climb gives you 250 — same legs, same day. That fade is durability, it's as individual as your sprint, and your plan probably pretends it doesn't exist.

2026-06-24 · 4 min read

Two riders can sit 30 points apart on heart-rate variability and both be perfectly fine. A single 'normal' line drawn for everyone tells you almost nothing. Here's why we read your HRV against your own history.

2026-06-24 · 5 min read

Ride easy for long enough and your heart rate creeps up even though your effort hasn't changed. Here's why heart rate is the wrong thing to chase in Zone 2 — and what to anchor to instead.

2026-06-20 · 9 min read