My loss is slight and I find that the aids bring up the volume of subtle noises quite a bit. There are LOTS of suble noises on a bike. So much so that I can't hear the music without a ear ache. I don't use'em while riding (just turn the volume up). But a friend of mine has profound loss and wears them all the time, on and off the bike. But then, without'em, she can't hear a freight train.