Biking shorts

Gerald looooooooves biking. He has bicycles in all shapes and forms. One for each category, type of road, you name it. Of course he has all specialized gear to wear with his bikes. He's even been buying bike gear for me!!! Such a sweetheart! But, one thing struck me, all sports gear are usually bright and colorful, tasteless much of the time, but biking shorts are always black... Why is that? I think I have a guess:

Maybe an x-ray would reveal more?

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