The physiological mechanics behind running aren’t always described, but I’ve found that the basic information below has made a huge difference in the way that I train and the athletic development of my body. So I wanted to share.
The primary goal of the heart during a run is to transport oxygen to the muscles via blood. The more blood I can deliver, the longer and faster I can run.
An athletic training centre in Colorado Springs works with Olympic athletes at 6000 feet above sea level. At these heights it is more of a challenge to breathe, so the body will adapt by increasing the number of red blood cells it produces, and in turn learns to transport oxygen more efficiently.
When we run, oxygen binds with our red blood cells through a protein called hemoglobin. Hemoglobin requires iron. By eating natural foods rich in iron and training regularly, we can help increase the blood volume in our bodies by as much as 10%. The dilating capacity of our blood vessels will also increase. As a result, greater blood flow will make us faster and increases our endurance.
Foods that are rich in iron include:
- beef, liver, organ meats
- clams, oysters, salmon
- egg yolks
- whole grains
- lima beans, soybeans, kidney beans, and green peas
- pumpkin seeds
- spinach, chard, kale
- broccoli and asparagus
- prune juice
Our bones sustain a lot of impact when we run, which is why a lot of people are reluctant to take on this sport. We tend to think of our bones as solid, unchanging structures. But they can actually undergo a remodeling process through gradual training.
Assuming we give them adequate recovery time, our bones will become stronger and denser. Their capacity to absorb ground impact forces will increase. In order to achieve this, our bones require the mineral calcium.
Our bones are responsible for providing calcium to the blood. This circulating calcium is needed for muscle contraction and plays an important role for runners. Regular exercise can also improve the circulation of calcium in our bodies.
Foods that contain a high amount of calcium include:
- milk & milk products
- broccoli and cauliflower
- peas and beans (especially pinto, adzuki, and soybeans)
- nuts (especially almonds, Brazil nuts, and hazelnuts)
- seeds (especially sunflower and sesame)
Much like bones, our muscles adapt to impact forces. When we strain our muscles, we are essentially creating tiny microscopic tears in our muscle fibre. As these tears heal during periods of rest, our muscles grow.
Running also improves the carbohydrate storage capacity in our muscles. The average adult can only store about 500 grams of glycogen (energy from carbs), whereas an elite runner may contain three times as much storage capacity in his legs. This allows the runner to hit greater speeds and cover further distances. We can work to increase our personal glycogen storage capacity by consuming adequate amounts of carbohydrates during our runs.
This is by far the biggest factor when it comes to running, and probably the least discussed. Our brains are the only organs that adapt to running WHILE we are running, instead of during recovery periods. It is also the most adaptable organ in our bodies.
Fatigue is something we often associate with our muscles, but it is actually controlled by our brain. Here is an excerpt from Performance Nutrition for Runners by Matt Fitzgerald that describes this process:
While you run, your brain constantly monitors feedback from your body – the temperature of your muscles, the amount of glucose in your bloodstream, the amount of oxygen reaching your heart – to determine whether your health is in any danger. When your brain decides that you may be running yourself into harm’s way, it will cut back on the electrical signals it sends to your muscles, forcing you to slow down. It is this “voluntary” slowdown rather than events in your muscles themselves that constitutes fatigue.
We can help our brain get on board with our running goals by consuming carbs. Our brain feeds off of carbohydrates, so by consuming simple carbs (most commonly provided to runners in the form of sugary drinks or gels) during longer runs, our brain gets the message not to panic – there’s an extra fuel supply to supplement what our body is already holding. As a result, it gives our muscles the electrical “green light” signals to keep going.
Running is truly a fascinating mind game, which is why I have found the above knowledge so powerful. If I can mentally grasp the mechanics behind the way my body runs, my brain can trust what I am physically capable of.
When I start to feel fatigued, I literally imagine the red blood cells transporting oxygen to my muscles. I imagine the extra glycogen storage in my legs being activated. I know they’re there. Once my brain understands that I’m physically capable of more than what it had previously assumed, it allows me to run longer. And faster.
I hope this knowledge produces the same effect for other runners.