I believe that fast hill walking is key to ultrarunning success, so one of my workouts is just that. Walk up the trail as fast as I can. Run down, and repeat. I can usually get to the top in about 22 minutes this way -- which is about a 14:40 pace.
I also do "intervals" on this trail. Yesterday's workout, for example, was to (after warmup) run for 1 minute, then walk for 1 minute, repeat until I get to the top. I can get to the top of the mountain in about 18 minutes this way, or about a 12:00 pace.
It is definitely more comfortable for me to walk up than run up. But I hope that gets better. One issue I have when running hills is low back pain. Searching for an explanation of why this is led me to this article by Bob McAtee NCTMB, CSCS.
A couple key points:
The biomechanics of running uphill are different than running on the flats. Running uphill, your stride length changes, your posture changes, and the physical demands on your muscles change. The steeper the hill, the more noticeable these changes become and the greater the likelihood that you'll experience low back pain.
First of all, as you go from flat ground to uphill terrain, your stride length shortens. This causes your leg muscles, especially hamstrings, to work in a much shorter range than they're used to, which may cause them to fatigue more easily. A shorter stride also means you're taking more steps than you normally need to cover the same distance, which in turn, requires your muscles to work harder over the same distance.
Running uphill causes you to use your muscles differently. As we all know, even if you're "in shape", when you do something new, you tend to be sore from it later. When covering uphill terrain, as the ground rises in front of you, you must raise your leg higher in front of you before placing your foot back on the ground. This works the hip flexors and stretches the gluteal (buttocks) muscles more. The push-off phase of your stride also requires more force since you are going up as well as forward. This especially works the gluteal muscles, the hamstrings, and the calves.
Uphill running also causes postural changes, the most noticeable being an increased forward lean of the upper body. The steeper the terrain, the more you naturally lean forward. Stuart Dole, an avid runner for the past 30 years and also a massage therapist from Tomales, CA explains it this way: "you need to lean over to keep your center of gravity over the center of thrust." This position puts added stress on your low back muscles, as they work harder to support you, "holding steady tension without any motion", according to Dole.
The solution? The article suggests that you ease into hill training, do some strengthening exercises such as squats and step-ups. Stretching and massage are also mentioned.Easing into anything goes against my "all or nothing" personality, but I'll see what I can do. Maybe limit my hill sessions to 1 or 2 days per week for a while (I did 4 last week!) to allow my body to adjust. I also plan to integrate more stretching into my daily routine. Of course I've been saying this for years...
Change is hard. Almost as hard as running hills.