Recommendations for Apple Watch bands for fitness

I would that that either

• the Solo Loop features a unique, stretchable design with no clasps, buckles, or overlapping parts, so it’s ultracomfortable to wear and easy to slip on and off your wrist. Each band is specially treated with UV to give the band a silky, smooth finish. It’s also swimproof and sweatproof, so it can go just about anywhere you want to wear it.
• the Braided Solo Loop band features a unique, stretchable design that’s ultracomfortable and easy to slip on and off your wrist. Created by weaving 16,000 recycled polyester yarn filaments around ultrathin silicone threads using advanced, precision-braiding machinery, then laser cutting the band to an exact length for a custom fit. The band offers a soft, textured feel and is both sweat and water resistant.
• the Sport Loop features a hook-and-loop fastener for quick and easy adjustment. The double-layer nylon weave has dense loops on the skin side that provide soft cushioning while allowing moisture to escape. On the reverse side, the attachment loops are securely anchored for superior durability.

would be good choices.

Those (and others) can be found here:

Buy Apple Watch Bands - Apple