Fast After 40: Master Your Cross-Training

Incorporating cross-training into your weekly training schedule can indirectly improve your fitness and performance.

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Incorporating cross-training into your weekly training schedule can indirectly improve your fitness and performance.

A few years back, I wrote an article for a running magazine in which I dismissed cross-training as a “kitchen-sink approach to training.” I noted that cross-training failed the specificity of training principle, which requires that training performed in practice be as close as possible to the exercise you’ll be required to perform in actual competition. In other words, swimming will make you a better swimmer, but it won’t improve your 5K time. I recommended cross-training only in times of injury. Not for the first time in my life, I was 100 percent wrong.

Cross-training refers to doing exercise that isn’t your primary sport. For runners, this can mean biking, swimming, rowing a boat or pushing a Sisyphean boulder up and down a hill, which is pretty much what hill reps already feel like for Masters runners who’ve skimped on strength training. Masters runners have long favored cross-training for three reasons: We can keep overall training volume high even as our bodies reject long miles and hard repetitions; it offers variety after decades of the same old same old; and it gives us a fitness outlet when injury strikes.

RELATED: Master Your Strength Training

But none of those reasons is the best reason for incorporating cross-training into your running regimen. The best reason is that cross training will make you a better runner.

First, the caveat: Many types of cross-training do fail the specificity of training principle. They don’t recruit the exact same muscle fibers (cells) and neural pathways as running. Therefore, they won’t directly improve running fitness.

Now, the reason to ignore the caveat: Cross-training can indirectly improve your fitness and performance in three game-changing ways:

1. It lowers blood lactate levels during intense running, thereby decreasing your fatigue level. It does this by increasing the number of MCT transport proteins in non-running, cross-trained muscle fibers—these proteins then import lactate from the blood. Basically, you turn non-running fibers into lactate drop zones.

2. It increases muscle glycogen stores in non-running muscle fibers, which can be converted to a carbohydrate fuel source and then exported to running muscles during training. You’re turning your body into a giant battery.

3. In cross-training activities that do comply with the specificity of training principle (e.g., pool running and the elliptical machine), you provide your body with an effective running performance boost without suffering the connective tissue and muscle fiber damage associated with normal, running impact forces.

While there are countless cross training options, the following six are a good place to start:


About The Author: 

Pete Magill is the fastest-ever American age 50+ at 5K (15:01) and 10K (31:11), the 2013 USA Masters Cross Country Runner of the Year, and the author of Build Your Running Body (The Experiment, 2014). Learn more about Pete at his website,