Changes in Body Composition
In Part 1 of the Faster Master Series, we talked about how our heart and lungs change overtime, and how we can mitigate the impact of this on our health and running performance. Now, let’s discuss the impact of aging on body composition, the implications for the masters runner, and what you can do about it.
Your Body’s Storage Strategy:
As we age, our bodies have a greater propensity to lose muscle, and to store more fat in its place. This is thought to be the result of natural changes in hormone levels. Decreases in growth hormone, testosterone, and estrogen can mediate a decrease in muscle mass over time. However, it is important to keep in mind that these changes are not drastic year to year, and can be impacted by activity. For example, there is research indicating that resistance training stimulates production of some of the above hormones, positively impacting muscle mass.
Farewell to Fast Twitch?
You hear buzz about this all the time in the running community. As we age, we “lose” our fast twitch muscles. This thought process often spurs runners transitioning from shorter events to marathons and ultra endurance races. Research does seem to indicate that when muscle break down occurs, the type of muscle fibers (type 2) that are associated with sprinting are impacted to a greater degree than the (type 1) muscle fibers associated with endurance activities. Although there is some truth to the age related changes in muscle fiber type, the magnitude of this change is often over emphasized. All you need to do is attend an All-Comers meet in Eugene to see proof of fleet footed masters athletes.
Similar to what we found with our research into the master’s cardiovascular system, these changes are compounded by changes in training. A decrease in training volume and intensity may fuel this decline rather than it being a consequence of aging alone.
Changes in the Calf:
One of the areas in which loss of muscle is most apparent in the masters running demographic is in the gastroc and soleus, the muscles that collectively comprise your calf. These muscles are essential for propulsion, or pushing you forward off the ground. This is necessary for all running, especially at faster speeds when you are powerfully pushing off of your toes. (We will dig into how this impacts your running mechanics in a future post, so stay tuned for more details on this).
Why Does “Tendon Stiffness” Matter?
Muscles are not the only part of the calf where we see general changes with age. The achilles tendon is often impacted as well. Tendons are essentially the component of a tissue that
connects muscle to bone. The most visible example of this in the lower body is the achilles. We want our tendons to be like a tightly coiled spring. When you hit the ground running, you want that impact to be transferred back into your leg to propel you forward. If your tendon is a tightly coiled (stiffer) spring, it is going to bounce that energy back up the chain pushing you forward efficiently. However, research has shown instances where, as a group, masters athlete’s tendons are less stiff. This means they are pushing off of a looser coiled, less efficient spring. This results in a greater loss of energy with less springy efficiency as you push off the ground.
This decrease in tendon stiffness is associated with age and is compounded by associated loss of muscle in the calf complex. These two factors increase the master athletes’ risk of achilles tendon injury. However, it is important to note that these changes are ASSOCIATED with aging, but not a direct cause of age! Multiple research studies on this topic have concluded that consistent long term exercise training works to maintain “physical function, muscle strength and body fat levels similar to that of young healthy individuals”(4). This is a fantastic affirmation that establishing and maintaining healthy habits, as discussed in part 1 can preserve muscle composition and tendon integrity.
What Can I Do?
Lift Purposefully.
Now more than ever it is time for you to develop a strength program that addresses your runner specific weaknesses. Especially if you are new to lifting, your weights don’t have to be incredibly heavy to be incredibly effective. Resistance training is one of the best ways to combat composition changes in muscle and tendons alike.
Avoid Being an “Active Couch Potato” (6)
It is common for runners to run, but aside from time spent running, they live a sedentary existence. Although some rest is important for recovery, movement throughout the day is what keeps us “well oiled machines”. Excessive time spent sitting compounds the effects of a slowing metabolism. It is also counterproductive to our overall physical health. So, try taking short walk breaks throughout the day, or break up your computer or TV time with body weight squatting breaks.
Don’t Drop Intensity
As discussed previously, maintaining intensity can help to preserve muscle composition. You can produce the higher level stress necessary to maintain and stimulate muscle mass via running hills, and with faster speed workouts.
These Strategies are Tried and True:
Let’s end off with another great example from the masters’ running community:
Let’s look at a master’s athlete we know who started running a decade and a half ago in her early forties. She is still seeing performance PRs from the half marathon to the 5k. How is she defying the physical changes associated with aging? She lives in a valley and runs hills almost every time she steps out the door in her running shoes. Hill running provides an excellent stimulus to add resistance, and thus intensity, to your training program. Additionally, this athlete does not live the “active couch potato life” as she supplements her running routine with dog walks, hikes, body weight strength, and cross country skiing. Not only does this lifestyle have a plethora of benefits for your cardiovascular health, as we touched on previously, it also helps fortify your physique against muscle loss and tendon changes!
For professional treatment with running injuries or niggles you may already be experiencing, feel free to reach out to us here at Zenith Performance and Wellness. Or, if you are in need of meaningful structure with your wellness program, we can help you with that as well. We want to help you make the most of your rehab, prehab, and training program so you can be the next master runner success story.
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5 Mckendry J, Breen L, Shad BJ, Greig CA. Muscle morphology and performance in master athletes: A systematic review and meta-analyses. Ageing Res Rev. 2018 Aug;45:62-82. doi: 10.1016/j.arr.2018.04.007. Epub 2018 Apr 30. PMID: 29715523.
6 Pfitzinger P, Douglas S. Chapter 5 The Older (and Wiser) Marathoner. In: Advanced Marathoning. Third ed. Champaign, IL: Human Kinetics; 2020.
7 Vingren JL, Kraemer WJ, Ratamess NA, Anderson JM, Volek JS, Maresh CM. Testosterone physiology in resistance exercise and training: the up-stream regulatory elements. Sports Med. 2010 Dec 1;40(12):1037-53. doi: 10.2165/11536910-000000000-00000. PMID: 21058750.