Wondering if there are any other competitive swimmers here. I notice that during a swim workout, it kills my battery. Typically in losing 10-12% of battery for every 1000 yards/meters. Fortunately, I do have a charger in my car so I’m able to top up after workouts. But today I got in the water at 92%, swam 4000 meters, and had 42% when I got to my car.

Any other swimmers noticed this phenomenon?