Does Strength Training Hinder or Enhance Running Performance?
Written by Melissa Dahn
As an endurance runner have you ever been told by your personal trainer or physiotherapist that weight lifting makes you slower? It was commonly believed that heavy weight training will increase muscle mass, make you heavier, and therefore decrease running performance. This is termed “the interference effect.”
The interference effect states that “adaptation to concurrent strength training and endurance training is diminished compared to separately training only strength or endurance” (1). It was theorized that since heavy resistance training requires slow, controlled movements, as per the principle of specificity it should in theory make you slower. But does heavy weight lifting actually hinder your running performance?
Believe it or not, heavy weight lifting can actually IMPROVE your running economy and performance!
One study performed by Eihara et. al. in 2022 compared heavy resistance training versus plyometric training for improving running economy and performance. The meta-analysis showed “heavy resistance training, especially with nearly maximal loads, may be superior to plyometric training in improving running economy and running time trial performance” (2). This makes sense because in order to run faster, as per the laws of physics, you need to be able to put more force into the ground. In order to train your body to produce more force you must train using heavy weights!
It is important to note that heavy resistance training, as an adjunct to running, was provided for 10+ weeks in Eihara et. al.’s study. This means that in order to see increases in running economy and performance, heavy resistance training needs to be performed over a long period of time - ideally for 10 weeks or more.
One factor that usually arises with athletes in training is fatigue! Fatigue management is essential for increasing performance. How do you perform heavy resistance training without getting fatigued? The general rule for heavy strength training is as follows:
Pick a weight that is >85% of your 1RM
Perform 3-6 repetitions, 2-6 sets
Rest periods are KEY!! You want to have 2-5 mins of rest in between sets for adequate recovery.
When working with athletes, endurance or not, my first question is always “What are your goals?” If we are dealing with an endurance runner, chances are that their goals are to improve their running time and economy, whether that be for a half-marathon, full-marathon, triathlon, or ironman. Once we set a specific goal we need to look at the big picture and break things down in order to manage training volumes and intensities according to where the athlete is in their season. We typically break these down into 4 categories/mesocycles:
Off-season: this is when we focus more on general adaptations and building load capacity. Generally, during off-season is when you want to accumulate the most training volume. In the case of an endurance runner, this is when you want to do the most weight lifting with a focus on hypertrophy, muscular endurance, and strength improvements.
Pre-season: this is when we want to get more sport-specific with our training. For an endurance runner this would mean reducing the amount of weight lifting - possibly increasing the load but reducing the repetitions - and increasing the amount of running. By managing the volume of lifting you will help manage exercise-endurance fatigue or overtraining.
In-season: this refers to the event day and the few days leading up to the event. This is when you want to do the least amount of lifting and running to prep for event day. When I work with athletes it is imperative that they feel the most rested and on top of their game during their peaking phase.
Post-season: this is your recovery period. This is when you de-load and allow your body to recover from the event.
If you are unsure of how to program heavy resistance training in with your endurance runs ask your physiotherapist or kinesiologist/strength coach.
References:
Eihara, Y., Takao, K., Sugiyama, T., Maeo, S., Terada, M., Kanehisa, H., & Isaka, T. (2022). Heavy Resistance Training Versus Plyometric Training for Improving Running Economy and Running Time Trial Performance: A Systematic Review and Meta-analysis. Sports medicine - open, 8(1), 138. https://doi.org/10.1186/s40798-022-00511-1
