Riven turns Apple Watch motion into three things: when a set starts and ends, which exercise you're doing, how many reps you did, and how close that muscle got to failure. The only sensor it uses is the Watch's 100 Hz motion sensor. No manual input at all. Say goodbye to manual logging.
The idea behind it is old and well-tested: reps slow down as you approach failure. Velocity-based training has used this principle for years, but it typically requires a sensor on the bar or a camera pointed at it, so it's mostly limited to barbell exercises. I built the same concept using only the sensors already inside the Apple Watch.
The tough part is knowing when a set starts and finishes, especially when you're moving around a busy gym, and differentiating reps from noise. After extensive ML training, we've gotten it to a point where it works really well.
App Store: https://apps.apple.com/app/riven-reps-muscle-failure/id6770362701 Website: https://riven.fit
Happy to answer any questions or hear your feedback!