Answer:

You are right on the money in thinking that you are placing too much weight on your forearms and wrists with the position you are in. Have the high seat and low handlebars means that you are leaning straight down on your forearms. It sounds like you are developing an overuse injury in them.

You may want to try lowering your seat a little and raising the handlebars so that you are in a more upright position when biking. This is less aerodynamic but it will help to alleviate the tension and stress on your forearms.

Another alternative you may wish to try is to use what are call "Tri-bars". You can get them at any good bike shop. If you've ever seen a triathlon or a bike race, they are the forearm rests that the cyclists use to remove all tension from the forearms and wrists. You simply lean forward and rest your forearms on the pads. This also has the advantage of putting you in a more aerodynamic position.

The only thing to be aware of when using Tri-bars is that you won't have as much control of the bike when using them. They shouldn't be used when you need to make quick turns. If you are mountain biking on trails, I wouldn't recommend that you use the Tri-bars.

You can also try doing some forearm strengthening exercises such as wrist curls or grip strength work. One of the easiest ways I've found for doing this is by squeezing a tennis ball repeatedly while you are watching TV.

Combine the adjustment in your biking style with Tri-bars and forearm exercises and you should see a fairly rapid improvement in your condition.