Does Strength Training Interfere with Aerobic Training? (and vice versa)

As many of you know I’m a physicist and I suppose by definition that makes me a bit of a nerd. I actually like reading papers from scientific journals and so I thought I’d share a few from the strength and conditioning world that I find interesting. The goal is to try and highlight one paper a week so we’ll see how this goes.

One of the topics of interest for fitness enthusiasts is how to balance strength training with aerobic conditioning. Typically people fall into one of two categories – meatheads who love lifting heavy but would rather watch reruns of Dr Quinn Medicine Woman than run a 5k OR those that enjoy running but worry that a heavy deadlift is going to explode their spine. Obviously at CrossFit 316 here in Wichita we think people can, and need, to be fit across as many domains as possible.

That’s why I found the paper by De Souza entitled “The acute effects of varying strength exercises bouts on 5km running” interesting. De Souza and his team studied the effects of leg training prior to running a 5km by breaking their subjects into 4 groups

1. 5×5 leg press followed by a 5km run
2. 5×5 leg press followed by a 5km interval run (1min run @ VO2 max : 1 min rest)
3. 2×15 leg press followed by 5km run
4. 2×15 leg press followed by a 5km interval run

Prior studies have shown that full-body strength programs with several different exercises did have a negative impact on subsequent continuous aerobic training. However, De Souza’s study applies more to our strength training model as we tend to focus our strength training on one specific exercise (i.e. squat, dl, press) before starting the metabolic conditioning or Workout of the Day.

During the 5km run De Souza measured oxygen consumption (VO2), heart rate (HR), rate of perceived exertion (RPE) and blood lactate concentration (La-). The bottom line for this study is that there were no differences in any of these variables for the 4 groups identified above when compared to their control sessions where no strength training was done. 

Interestingly enough, in another paper De Souza applied the same tests in the reverse order to determine if aerobic training had an impact on subsequent strength training. The results of that study showed that aerobic exercise did have a negative impact on strength endurance training and a trend towards impairment of maximal strength training.

Conclusion – Concurrent training of strength and aerobic exercises is fine as long as you do the strength training first AND you limit the strength training to a specific muscle group or exercise. So no more excuses – you can be strong and fit! Get to work…