Features
Compatible with
Your Whole Season on One Screen
Most tools show each sport in its own silo. OSO folds every ride, run and swim into one load model, so form means one thing and you always know which way it is moving.
- Fitness, fatigue and form from your unified training load, with a forecast of where planned sessions take you.
- Health and recovery: HRV, resting heart rate and sleep, read together with your training.
- A dashboard you arrange: add, remove and reorder widgets and metric fields until it shows what you actually check.
- Plain-English insights that point at what is driving your form right now.
- Compare any two rides, weeks or metrics side by side, and read the relationship rather than just the numbers.
- Yours to keep: export your whole history whenever you like, and the essentials stay free.
Every Session, Read Closely
Upload a ride and OSO reads it the way a good coach would, working out how hard it really was for you and what it built.
- Zoomable streams for power, heart rate, pace and cadence, with a map cursor that follows your scrub.
- Sport-correct zones: runs are scored on your pace zones, rides on your power.
- Durability and decoupling: how your second half held up against your first.
A Model of You
OSO fits a critical power model to your own best efforts and updates it as you train. The result is a profile built from what you have actually done, not from what a formula assumes about someone your age.
- Critical power and W′ for cyclists, critical speed for runners, estimated from your own curve.
- Your limiter, named: the energy system furthest behind, with the gap in percent.
- A session to close it: one tap loads a workout template aimed at that limiter.
- Personal records across every duration, kept current from every upload and tracked alongside the model that explains them.
Build the Session, Keep What Works
Design a session interval by interval, every target pulled from your own zones. Then save the whole thing, or just the block that worked, and drop it into the next one.
- Every step type, in any order: warmups, steady blocks, repeating intervals, ramps up and down, recoveries and cooldowns, dragged where you want them.
- Targets in your own units: power as %FTP or watts, pace for runs, or heart rate, switched across the whole session in one tap.
- Templates and a growing library: start from a sweet spot, threshold or VO2 template, then save the full workout or a single section and reuse it in the next build.
- Notes, a live preview, and send to device: annotate any step, watch duration and effort update as you go, then push it straight to your head unit.
- Fueling for the session: carbs, fluid and sodium sized to how long and how hard it is, shown before you roll out.
No Population Tables
Every threshold, zone and grade in OSO is computed from your data against your physiology. If a number cannot be traced back to something you actually did, we do not show it.
Not an AI Coach
OSO reads every session back to you in plain English, but that read is deterministic sports science run on your own data, not a chatbot generating plausible sentences. An AI model writes a fresh answer each time and drifts as it goes; OSO works from defined inputs through a fixed, finite set of conclusions, so the same session reads the same way today and a year from now.
It computes, it does not guess. A language model predicts the next likely word; it has no model of your engine, so it matches phrasing, not physiology. Every OSO threshold, zone and verdict comes from your own recorded efforts against a named model, so it describes you and not a pattern in text.
It shows its work. Ask an AI coach why and you get more confident prose. OSO names the evidence behind every claim, from the Critical Power framework to the Banister impulse-response model, each cited on the Training Science page, so you can check it rather than trust it.
And it stays quiet when it cannot be sure. A plausible sentence is not a true one, and a confident wrong answer is worse than none at all. When your data cannot support a conclusion, OSO says nothing rather than inventing one to fill the space.
Free while in private beta
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