To cover tattoos
They are bandages to assist compromised muscles, that is all.
It is Kinesio tape, used for sore muscles, injuries, and healing. Many Olympic athletes have used it this year.
Many divers wear Kinesio Tape on their backs. Kinesio Tape is used to help manage pain for a variety of bone, muscle, and joint issues.
Scuba divers also wear lead weights on a belt