Look, cyclists have great glutes. Your butt is involved in the actual action of cycling, and continuously working them results in a backside that’s as toned as someone with perfect pitch.
Sure, they might go a bit bow-legged after a long ride, thus rendering their lovely asses invisible. But in daily life their buttocks will shine, iridescent for all to see. The only thing that will make your friend’s more jealous is when they realise that your backside is also great, and together you make a frightfully beautiful butt duo.