I could never have long nails as a PT and one reason is that I gave a lot of transverse friction massages. But I was sick and tired of not being able to have long nails so I had a stroke. I can grow my nails long now. A transverse friction massage is when you rub back and forth perpendicular to a tendon. It’s always over a tendon. Usually if you have tendonitis, you’ll get a transverse friction massage. It breaks up scar tissue and increases circulation to the area promoting healing. I would do it for I think about 5 minutes. I don’t know, I forget. They hurt at first but then they feel good.