The last thing you want in the middle of a big game is to have your sunscreen drip into your eyes. (If you've ever had sunscreen in your eyes, you know how much it burns.) Look for a sunscreen that's labeled "water-resistant" or "sweat-resistant," like Coppertone Sport Ultra Sweatproof, Hawaiian Tropic Ozone Sport Sunblock, or Banana Boat UltraMist Sport Performance Continuous Spray. A water-resistant sunscreen will maintain its SPF for as long as 40 minutes underwater (unless you rub it off).
Even though you may still see sunscreens labeled "waterproof," there really isn't any such thing. No sunscreen can be entirely waterproof, because all of them will eventually wear off if you submerge your body in water for long enough. Water-resistant is the more accurate label. No matter how water- or sweat-resistant your sunscreen is, you'll need to reapply it about every two hours, and sooner if you're sweating a lot [source: Skin Cancer Foundation].