For heavy training days, the On Cloud X is our weapon of choice. Great for mixed-sport workouts when you need a stable yet agile shoe that can handle it all - HIIT class, long runs on the track, plyometrics and everything in between. On's famous Swiss-engineered Cloudtec® outsole in Helion™ superfoam is specifically made for explosive movements in any direction. Sidewalls on the outsole provide stability, keeping your feet locked in place during dynamic workouts. The engineered mesh upper is highly durable yet fully breathable for max intensity efforts.