I enjoyed this beautiful fall evening on the Gateway, and took the opportunity on one section to take some clips of different hand positions. The reason for doing this is that a couple of weeks ago when I was riding on the trail I noticed that other users were getting way out of my way. It was obvious to me that they were concerned about me going out of control and running in to them. Since then I've been trying to focus on quieting down my upper body movements, and one aid in doing that is to hold my hands in particular positions.
I videoed three situations: hands quite at my sides, hands on thighs, and hands behind the back. You can look for yourself, but I think that hands at my sides is just as good as any of the other three. I spend a lot of time today on the trail with hands behind my back, and I really could build up some speed and control that way. In fact, it was a lot of fun, but I don't think it looks particularly good from the hiker's standpoint. I didn't show how it looks to ride with one hand on the front bumper. If the rider is male, I think it looks like the rider is hanging on his nuts, so I that's not an option I'll consider anyway when riding moderate terrain..
My tentative conclusion is that when meeting others on the trail, having hands hanging naturally at my sides is the least likely to cause hikers to be concerned about their safety. .
I had such a blast today bombing down the trail with hands behind my back that I'll keep doing that anyway, even if it looks a bit awkward to the hikers.
Hand position video (8MB)