I have historically had IT Band problems. Once I learned what it was, I started stretching every other day and have bought a Stick to help massage out the sore spots. I have massages every month, sometimes every 2 weeks (I go to a massage school). I thought I was pretty much over the pain until this past Disney Marathon. My IT band didn't even bother me in my training runs until the end of the last long one, when I felt a little twinge around mile 20.
Because of that "twinge", I took my IT Band strap with me to the marathon Just wrapped it around my hydration belt. I am glad I did. By mile 7 or 8 I was starting to feel the pain in my knee. It is usually on the outside of my knee and can stop me in my tracks. I worried because there were times in the past where I couldnt even walk once it started hurting. I started seeing my first marathon go out the window. I put the band on and used Bio freeze the rest of the way. Unfortunately I waited to long to put the strap so I had to suffer and limp for another 8 miles until the pain subsided. I was running near the castle and didnt want to stop until I was through. If I would have stopped right away and put on the strap I probably would have been fine but I was coming close to the castle and didnt want to stop.
I ran a half a month ago and had the same problem. Coming down a bridge around mile 9 I felt the pain in my knee. This time I stopped right away, put on a bit of BioFreeze and secured the strap. I was fine from there on out.
It's strange, because I do not have any pain in my training runs, just races. Maybe it is pushing it, running hills, etc. I know that the goal is to not have the pain, but just in case I never run without taking the strap with me. I dont usually use it, just carry it on by belt.
So, to make a long story short - yes a strap does work. I would not have finished the marathon nor my last half without it. I bought mine at Sports Authority since my local running shop did not have any.
Good luck,
Duane