Last updated: August 30, 2026
Kurbl controls a piece of exercise equipment that you work hard on. Please read this before your first ride. It is not fine print; it is the condition for riding safely.
Kurbl is a game and a training tool. The app is not a medical device. It makes no diagnosis, does not monitor your health, and does not detect medical emergencies. Values such as power, cadence, speed, or heart rate are there to orient you during training and are not intended for medical purposes. Showing a heart rate is expressly not monitoring your heart. Sending rides to Apple Health or Health Connect does not change any of that.
Talk to a doctor before you start training, especially if you have been inactive for a while, have a pre-existing condition (cardiovascular, musculoskeletal, or respiratory, for example), are pregnant, take medication, or are under 18. This matters most for hard sessions such as the ramp test or heavy intervals.
Stop training immediately and get medical help if you feel chest pain, pressure or tightness, shortness of breath, dizziness, nausea, an irregular heartbeat, visual disturbance, or unusual exhaustion. No interval and no in-game goal is worth pushing through a signal like that. The app never asks you to keep going against how you feel, and you can pause or end any session at any time. In the ramp test the quit button is visible throughout and does not ask you to confirm: stopping there is the result, not a failure.
The sessions, courses, and ramp test included in the app are based on widely used training patterns. They are general suggestions, not a training or therapy plan built for you. They do not account for your health, because the app does not know it. Adjust volume and intensity to how you actually feel, and bring in a qualified coach if you want training tailored to you.
The ramp test deliberately takes you to the point where you stop. Ride it rested, not at the end of a hard day, and not when you feel unwell. Make sure someone is nearby or that you can call for help if something happens.
Kurbl controls your smart trainer. Pedaling resistance changes as it does so, sometimes sharply and sometimes suddenly: at the start of an interval, on a steep ramp, when you change gear, or when a connection drops and the device falls back to its default state. Expect it at any time. Ride carefully for the first few minutes, until you know how your equipment behaves with the app.
Kurbl announces a coming climb with a road sign. Do not rely on it alone. A sign can be missed, and on a route you imported yourself a climb can hit harder than it looks on screen.
In fixed target power mode, often called ERG mode, the trainer raises resistance when your cadence drops. As you slow down it gets harder, which slows you down further. If you find yourself in that spiral, do not fight it. End the target in the app or stop pedaling.
When you end a ride, Kurbl hands control back. If the app or the phone crashes first, your trainer can stay at the last target it was sent. If that happens, get off carefully and reset the device following the manufacturer’s instructions.
Not every setup measures power. If you only have a cadence sensor, Kurbl calculates power from your cadence and a figure you provide. If nothing transmits at all, the app sets a wattage in manual mode and you set the resistance by hand. In both cases the app labels the number as estimated.
That is entirely good enough for the game and expressly not good enough for judging how hard you are working. An estimated number can be well off your actual load, in either direction. In those cases go by how you feel, by your breathing and, if you wear a strap, by your pulse, not by the wattage on screen. The same goes for your reference power: until you have entered something or ridden a ramp test, the app works from a default value that knows nothing about you.
On a route you imported yourself, the gradients come from that file, not from a session someone designed for indoor use. A real road can contain stretches that are far harder indoors than outside, because you have no momentum, no room to move around, and no headwind. Elevation data in GPX files is also often imprecise and can contain short, very steep spikes that do not exist in reality.
Look at the elevation profile before you ride, start with something moderate, and shift down in good time instead of forcing a ramp out of the saddle.
Setting the equipment up safely, judging what you can take, and deciding whether to start, continue, or stop a session are yours. Our liability is set out in the Terms of Use. Our liability for death, personal injury, and damage to health is unaffected by that and is not limited by this guidance.