The Principle of Specificity states that in order to become better at a particular sport, you have to practice that sport. This is particularly true for running. With that said, supplementary training remains important since the body and mind can only handle so much training repetition. For runners, perhaps the most important ancillary work is strength training.
Nikki Ditsch a coach for Endurance Base Camp in Lexington, Kentucky, says that while running should be your main focus when training for running races, many athletes take it to the extreme. "For a lot of runners, I think most of the emphasis is placed on the run training, and strength and conditioning are neglected," she says. To be sure, there is no substitute for going out and pounding the pavement. However, new research highlights how strength work can help support your legs over the many miles of training.
A study published in the European Journal of Applied Physiology compared several forms of strength work done in conjunction with endurance training. The participants were instructed to utilize strength training 1 to 2 times each week and endurance training 3 to 4 times each week over an eight-week period. At the conclusion of the training, researchers identified a significant improvement in strength and power. Interestingly, they also saw gains in peak running speed and endurance performance.
Ditsch says she's seen this play out with the runners she coaches. Not only does strength training make your muscles more powerful, it can help you prevent injury. "Strength training simply makes you stronger, which, if done properly, makes you faster," she said. "It can make a runner more powerful, improve run form, correct muscle imbalance and prevent injuries."
Indeed, when you run day in and day out, certain muscles and connective tissues are neglected. While it's okay to strengthen the most specific muscles relevant to running, muscle imbalances and fatigue over a long distance can lead to overcompensation injuries.