Two tips from today's short trail run. When trail running and your blocked up sinuses cause your molars to ache with each hard foot fall, such as when you're running down a steep downhill, try to run 'softer' by cushion each step. This is not the same as running slower, it is more about using your legs as shock absorbers. This not only reduces the impact in your head, but it's good for the joints as well.
The second tip is while you're running across, and down, technical terrain that requires your attention, don't concentrate on the first tip too much lest you miss that sudden drop off, putting you in complete violation of tip #1.... I think I saw my dog smirking at my inability to multitask.