I’ve had a Whoop for 3 weeks. I used a CorSense prior to that and the numbers didn’t make much sense to me based on training, sleep, meds, stress, etc. I used a VivoSmart for sleep tracking before and it was similar to the Whoop but I couldn’t seem to make much of the data. The Whoop has provided a lot more information in all these aspects. The most important thing has been the sleep tracking so far. I tend to hover around 90% efficiency which was news to me so now I spend more time in bed. Reviewing the sleep and recovery data gives me the notion that someone training hard as well as only sleeping 5-7 hours is severely limiting their potential progress.
Obviously the Whoop needs more data but it’s starting to get a lot better at matching up with how I feel and how my workouts go.