As a runner, your weight training goals are specific. You want to:
- Make your body more resilient to damage.
- Increase balance to facilitate running over technical terrain.
- Work to prevent injuries from hyperextension.
- Decrease recovery time after a race.
- Avoid gaining excessive weight.
More: Strength Training vs. Cardio - What's Better?
Over the last nine years or so, I've experimented with quite a few different exercises and volumes. This is the result of my experimentation in chronological order:
Traditional Body Building Plan
I used free weights and weight machines exercising muscles in isolation, alternating muscle groups from day-to-day, six days a week. This plan was the least effective of all the plans I tried with the exception of the next. It produced the greatest muscle mass, but did very little for all five of the above criteria.
No Weight Training
This was an unmitigated disaster. I could barely finish a trail marathon with this "plan."
More: 3 Strength Training Workouts for Beginners
High Rep/Low Weight Training
This plan used the same basic exercises as the traditional body building plan. It also did not work well. It didn't seem to increase muscle mass quite as much, but may have been a function of slightly decreased volume.
Crossfit/Crossfit Endurance
This plan was spectacular, though the lack of long runs doomed me for endurance racing. It accomplished all of the five criteria and made me significantly faster.
A major drawback was overtraining leading to injury potential. This was a demanding program that usually required around an hour or more of working out at a very high intensity every day.