I do triathlons (swimming, biking, running) and when it's hot or humid, I get pimples on my buttocks. What should I do?

It is recommended to remove your cycling shorts as soon as possible when you get hot or sweaty, and even consider changing into a fresh pair after swimming. After your workouts, you could apply over-the-counter hydrocortisone cream twice a day for at least 3 days to help with any irritation. It is also important to wear looser clothes to allow your skin to breathe. This should help alleviate any irritation or bumps that form on your skin.