What are these parallel strips some olympians have on their backs?

I see that several of them - mostly swimmers, I guess - have two parallel strips - same color - attached to their backs. Looking like a pair of bandaids about 2 inches wide and 6 inches long, they run from their lower backs down into their trunks, away from view. What the hell are these things?

Kinesiology tape, I’m guessing. As for whether it does anything or not, I couldn’t tell you. Elastic therapeutic tape - Wikipedia

Pretty much a placebo. Trials have been done but blinding is difficult to achieve, even then any effects seen have been insignificant.
Of course placebo is important to athletes so we shouldn’t be surprised that they’ll try anything to get a mental advantage.

I’m not sure exactly what type of tape those strips are made out of, but I think I’ve seen other athletes at the Olympics wearing them. I was watching men’s beach volleyball a little while ago and one of them had two strips of tape on either side of the back of their neck peeking out of the top of their jersey.

Speaking as a former athletic trainer and someone who knows how to apply athletic tape to all kinds of body parts, I can’t think of any possible “supportive benefit” to applying tape to the neck or back in that manner. Taping a joint (e.g. finger, wrist, ankle, shoulder, knee, etc…) to prevent injury or to provide support to an injured joint has well known benefits (although even this benefit is sometimes exaggerated). But just applying strips of tape to the torso seems unlikely to have any benefit. So it’s probably some flavor of woo that purports to have vague benefits and is likely all placebo effect.

Related anecdote:

About ten years ago, I was a trainer for a college volleyball team, and the coach spent a buttload of money for a case of special “magnetic athletic tape” that was supposed to help prevent injuries. It cost probably 5x the cost of regular athletic tape. Given that the team did not have an unlimited budget, I thought it was a stupid thing to waste money on, but as a lowly student volunteer I didn’t say anything to the coach about it. If players asked me, I did say that it was unproven/unlikely to do much.

BTW, I actually brought in some small magnets and a compass to test the tape, and it had no magnetic field as far as I could tell. I don’t think a company should be able to legally sell “magnetic tape” and isn’t magnetic.

Article.

Along similar lines I saw a male diver last night who had some black thing on his right shoulder that looked like the Alien had glommed onto him to inject eggs. Any idea what that thing was? It did not look subcutaneous like a tattoo. The pattern looked too intricate to be just a bunch of tape.

It was a bunch of tape.

I thought at first they were hiding tattoos of rude words or images (or IOC forbidden logos). “Kinesio Tape” makes more and less sense at the same time.

An announcer said that he did it as a decoration. At least there’s no (self)deception involved there. As opposed to the woo woo strips that seem to have magical powers (sort of like the necklaces that I was asking about in another thread).

I overheard a swimmer at the University Natorium whispering to gullible spectators that these were additional straps to hold his athletic supporter in place while swimming. As in, ‘my balls are so big, they need extra supporting tape’. Based on that, we’ll soon see this tape stretching up to and over their shoulders!

Funniest part was that they believed him, and were repeating this to others. And other swimmers were having a great time laughing about it.

I expect to see it on the internet soon, as a serious explanation.