Though strength training for runners can seem counterintuitive at first, it is an essential part of maintaining sufficient tone in order to avoid overuse injuries. After all, runners want to stay lean as opposed to bulky, so they can maintain their stamina over the long haul. Since running can take a major physical toll on the muscles, tendons and ligaments in the legs, feet and lower abdomen, avid runners must tone these areas with consistent weight training in order to avoid injury (while seeking to reach their next goal).
Since running is such a goal-oriented form of exercise (with respect to distance and speed), you must make sure that your body is ready to make the leap to the next step.
If you limit yourself to running as your only source of exercise, you risk introducing unhealthy imbalances to your overall muscular structure within your lower extremities. Everyone has a different style of running, each working slightly different muscles. Working these muscles alone on a consistent basis will lead to an imbalance, as some muscles (such as the hamstrings and quadriceps) will get constant work, while others (like the gluteals and hip adductors) will get less of a workout.
Such imbalances can lead to compensatory mechanisms, whereby the stronger muscles will need to compensate for the weaker ones during movement (since they have become under developed). Such compensations can easily lead to overuse injuries, for those muscles needing to carry more of the weight of the exercise. Therefore, a more thorough approach to toning all of these muscles would lead to more balanced running mechanics and avoidance of overuse injuries.
Breaking It up
Since most running-related injuries are due to simple overuse (i.e., running too often or too far), breaking up the routine with a different type of leg exercise can break things up in order to assure that you’re not overdoing it in one area. So, make a schedule. Maybe plan to run every other day, increasing the goal distance each day, and head to the gym on the non-running days earlier in the week to give your lower body a more complete workout (while still tackling the longer goal runs at the end of the week). Not only will this break up the monotony and possible boredom, but it will allow you to strengthen the weaker muscles in your leg so the stronger ones aren’t overcompensating.
Don’t Do Too Much
Remember that while strengthening the leg muscles that aren’t utilized as much during running will improve overall form and avoid imbalances, you should always train in moderation. You shouldn’t be focusing on increasing weight during training, but instead you should be attentive to how your muscles are relaxing. Don’t push them too far or you may be adding too much bulk muscles, which may hinder your running technique.
For competitive runners, consider taking some time away from weight training in the week or two leading up to your race, especially if it is a longer distance race. You want to make sure that when you reach back to give it all you have, there’s something left in the tank.