Its where their batteries go.
To keep their skin looking tight.
These divers, as well as divers from many other countries, are wearing Kinesio Tape, which is used to help manage pain for a variety of bone, muscle, and joint issues.
It's Physiotherapy/Kinesiology tape, for support of injuries.
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.
Kineso tape
kinesio tape
It's kinesio tape, sort of an alternative to an elastic bandage:
To proect their bones from breaking
Tape
It is tape. Used for protection and strength.
It is to help protect injured muscles and joints