Why Cross-Training Is Essential (and Improves Your DNA)

While it's necessary to train in ways that are specific to your chosen sport, cross-training is also an extremely beneficial training component, one that can benefit you all the way down to your DNA.

Brock Armstrong
6-minute read
Episode #394

Cross-Train Your Genes

Research from 2014 on the reprogramming of the epigenome and the transcriptome in human skeletal muscle after training showed scientists that exercise actually changes the shape and function of our genes.

The human genome is as complex and dynamic as you can imagine. Depending on what biochemical signals they receive, your genes are constantly turning on or off. When our genes are turned on, they express proteins that trigger physiological responses all over the body, both good and bad.

This is where epigenetics enter the equation. I know this sounds complicated but hang in there—it is worth it!

Research from 2014 showed scientists that exercise actually changes the shape and function of our genes.

What scientists call epigenetic changes occur on the outside of the gene, through something called methylation. During methylation, methyl groups (clusters of atoms), attach themselves to the outside of the gene and make the gene more or less able to receive and respond to those biochemical signals.

Scientists know that methylation patterns change when we make lifestyle changes, like eating certain foods (and not eating others), but a lot less was known about how exercise affects methylation.

Which brings us back to the 2014 study where scientists at the Karolinska Institute in Stockholm gathered 23 young, healthy men and women, and performed muscle biopsies on them. They then asked the 23 participants to exercise half of their lower bodies for three months. Yes, I said half of their lower bodies.

They did this by having the volunteers ride a bicycle using only one leg, leaving the other leg dangling there, unexercised. Ingeniously, this turned one of their legs into a "control group," of sorts. Both legs would experience methylation patterns that were brought on by their normal everyday lifestyle but only the leg that did the pedaling would show the changes related to exercise.

After the one-legged pedalling at a moderate pace for 45 minutes, four times per week for three months, the scientists did more muscle biopsies and calculated the results.

The researchers found that more than 5,000 sites on the genome of the muscle cells from the exercised leg had new methylation patterns. And the genes that were affected are genes that are known to play a role in metabolism, insulin response, and inflammation within muscles. In a nutshell, the genes that were methylated are the ones that affect how healthy and fit we are.

The gene changes were not found in the unexercised leg.

After all this, how does this relate to cross-training? Well, here’s the thing: the gene changes were not found in the unexercised leg. Do you see where I am going with this?

Ok, back to the vitamin analogy. Let’s say that you get plenty of "vitamin walking." The genes associated with how healthy and fit you are get expressed in the muscles you used for walking. But, like the unused leg of the cyclists in the study, the rest of your muscles are left unnourished and those genes are left unexpressed.

This is exactly why cross-training, not only in your chosen sport but in your general lifestyle, is so important. It is also why I am much more interested in tracking "planes of movement" and "number of limbs used" than I am in counting calories. (Even if the calorie counters were even close to accurate).

10 + Ways To Cross-Train Your Day

So, aside from making sure you get all the benefits of cross-training in your fitness regimen, how can we add more vitamin-rich movements into our day? I am sure you can get creative but here are some ideas to get you started.

  1. If you sit down to put your shoes on, try standing.
  2. If you usually pick things up off the floor by bending at the waist, try squatting.
  3. When it is not dangerous (or too awkward), walk backwards or do some side gallops.
  4. If you usually carry a backpack, try carrying it on your chest or in your hand.
  5. If you use the computer mouse with your right hand all day, try using your left.
  6. If you have been sitting in a chair during the day, sit on the floor in the evening.  
  7. Simply get your arms up over your head, I bet you don’t do that very often outside of yoga class.
  8. If you usually hold your phone down by your stomach, hold it up right in front of your face.
  9. When you are waiting for the coffee to brew or the street light to change, do some arm circles, knee bends, ankle rotations, shoulder rolls or simply move any other body part you can think of.
  10. If you only pedal your bike with one leg, try pedalling with both!

Move as many limbs, in as many directions, on as many planes as you can.

If you are a runner, it is a good idea to cross-train in the weight room to build strength and stability. If you are a weightlifter, throwing in the odd cardio session or yoga class can be a great way to help stay flexible and lean. If you are a swimmer, hitting the rowing machine or elliptical trainer can be helpful to avoid repetitive use injuries. And if you are a human on this planet, moving as many limbs, in as many directions, on as many planes as you can is one of the best ways to stay healthy and fit on a genetic level and beyond.

At the conclusion of that 2014 study, one of the researchers stated, "Through...a lifestyle change that is easily available for most people and doesn’t cost much money, we can induce changes that affect how we use our genes and, through that, get healthier and more functional muscles that ultimately improve our quality of life." Need I say more?

For more cross-training info, genetic tips, and to join the epigenetic conversation, head over to Facebook.com/GetFitGuy or twitter.com/getfitguy. Also don't forget to subscribe to the Get-Fit Guy podcast on Apple Podcasts, StitcherSpotify, Google Play or via RSS.


About the Author

Brock Armstrong

Brock Armstrong is a certified AFLCA Group Fitness Leader with a designation in Portable Equipment, NCCP and CAC Triathlon Coach, and a TnT certified run coach. He is also on the board of advisors for the Primal Health Coach Institute and a guest faculty member of the Human Potential Institute. Do you have a fitness question? Leave a message on the Get-Fit Guy listener line. Your question could be featured on the show.