I just walked 5,000 steps with the new Galaxy Watch 8 Classic on my left wrist and the Apple Watch Series 10 on my right wrist to find out which flagship smartwatch is the more accurate fitness tracker.

On the Watch 8 series, Samsung's Galaxy AI can help you train for a marathon or a 5K with a custom-generated plan based on a 12-minute fitness test. The watch will even offer active feedback and coaching to help you stay on pace while you're on a run.

Commentary: Tracking vascular load and antioxidants, as well as AI sleep and running coaches, all sound promising. Will they actually live up to Samsung's claims?