Updated: Sep 12, 2018
Once again we will address the age-old question, if I want to improve endurance how can strength training help? Many times when endurance training is the focus strength takes a backseat and that's when injuries occur, maybe not immediately, but eventually. Although the training needs of runners in general include strengthening the lower body and core in particular, trail running comes with unique demands. Paying particular attention to stabilization of the ankles and strengthening the hips as well as agility work will prepare the body for the inconsistent terrain that trail running entails. Single leg strengthening should be a part of any running plan to provide balance as well as strength for stabilization of the major joints in the lower body (hips, knees & ankles). Incorporating balance work on an unstable surface such as an Airex pad is also helpful to avoid injury. Both of these things will provide strength through the lower body and the core.
If you are someone who is used to running on a paved surface, it is wise to begin your trail running slowly. Perhaps begin on the trail for scheduled shorter runs, once you have begun adding some balance and single leg strength work to your workouts. The demands of the uneven terrain, roots and rocks will require more agility than a run on the road and the following exercises will help prepare your body...
1 leg calf raises
1 leg squats
Fit ball bridges
Medicine ball chops on the Airex pad (or throw pillow if you are doing this at home)
Variety of plank positions (traditional, side, 1 leg, etc.)