Q: Won’t I gain body fat if I cut back my running volume and replace it with resistance training?
A: No! Contrary to popular belief, resistance training is extremely valuable for burning fat – primarily due to something known as “Excess Post-Exercise Oxygen Consumption” (EPOC). This is just a fancy way of saying that after any exercise session, our metabolisms are elevated significantly. Research has shown that EPOC directly related to how intense our exercise sessions are; the more intense the effort, the more metabolic “debt” we accumulate. For this reason, activities like sprinting and weight-training – both of which are much more intense than steady-state jogging – have a ton of merit in “battling the bulge.” Amazingly, a single bout of resistance training can elevate the metabolism for more than 48 hours – and favorably affect endocrine and immune status in a manner that is conducive to fat loss. If you want to be lean, you have to lift weights! Additionally, you rarely see ultra-endurance athletes with very low body fat percentages – and it’s largely because all the mileage they do leads to higher levels of cortisol and lower levels of testosterone in the body. This endocrine fluctuation leads to a loss of muscle mass (which burns a lot of calories) and an increased tendency to store body fat. Fortunately, resistance training has been shown to have favorable effect on testosterone levels chronically (good for men and women…trust me). By keeping your hormonal status in check by including some resistance training, runners can get faster and leaner!
Q: I have limited time to train; wouldn’t I be better off just running if time is limited?
A: Obviously, this would depend on how you define “limited” – but it’s been my experience that runners can always “make” time to run, but will only “try to find” time to resistance-train. Generally speaking, you can bang out a run here and there without much time preparation, so it’s best to schedule your 2-3 resistance training sessions ahead of time. Additionally, in some cases, you can incorporate some body weight resistance training exercises as part of your warm-up – but this certainly won’t cover all your needs. Also, don’t forget the study I cited earlier about the group of endurance athletes who saw appreciable gains in performance by replacing 32% of their running volume with resistance training. If you run six days a week, try moving to four runs and two lifting sessions – and watch your times improve dramatically. Anyway, my feeling is that from a body composition, health, and performance standpoint, you need to make time for two lifting sessions per week regardless of how much you run.
Q: Won’t resistance training will interfere with my running?
A: No, provided you schedule your running sessions appropriately. Ideally, you would lift on days that you don’t run, or pair your lifts up with your tempo (sprint) sessions in order to “consolidate” your most intense training and allow for better recovery.There is some research to show that running efficiency is impaired slightly for up to eight hours post-exercise, but you should be fine if you lift and run on separate days. I always prefer that my athletes lift before they run, though; you always want to do your speed and power work before you move on to endurance training.
Q: Won’t resistance training make my muscles bigger? I don’t want all that weight holding me down!
A: Endurance training by its very nature is not conducive to muscle growth (especially in a female population with lower testosterone levels). The sheer volume of exercise makes it difficult to get in enough calories to support muscle mass gains, so the effects of resistance training are largely confined to muscle density (tone), strength, and overall efficiency rather than actual increases in muscle size. If it was so easy to get “bulky,” there would be a lot more bulky people walking around!
Various scientific research findings in regards to the health benefits of resistance training to an endurance athlete:
- French researchers found that the addition of two weight-training sessions per week for 14 weeks significantly increased maximal strength and running economy while maintaining peak power in triathletes. Meanwhile, the control group – which only did endurance training – gained no maximal strength or running economy, and their peak power actually decreased (who do you think would win that all-out sprint at the finish line?). And, interestingly, the combined endurance with resistance training group saw greater increases in VO2max over the course of the intervention.
- Scientists at the Research Institute for Olympic Sports at the University of Jyvaskyla in Finland found that replacing 32% of regular endurance training volume with explosive resistance training for nine weeks improved 5km times, running economy, VO2max, maximal 20m speed, and performance on a 5-jump test. With the exception of VO2max, none of these measures improved in the control group that just did endurance training. How do you think they felt knowing that a good 1/3 of their entire training volume was largely unnecessary, and would have been better spent on other initiatives?