Mechanisms

The debate over limitations in human performance has been waged for decades. In the endurance sports world, the commonly-held perception is that the cardiovascular system is the primary limiting factor. The belief expressed by many endurance sports coaches is that maximum VO₂ and lactate threshold are the primary culprits - and thus, we need to track and scrutinize the appropriate training parameters - namely, heart rate.

But here are some thoughts to refute those claims - to take our focus away from the past and turn it towards the future.

This week marks the 13th anniversary of my first McKenzie course. I would bet that your first thought would be "why remember something so seemingly trivial - it was just a course"! But in our lives, we remember moments in time that shaped us and our perspective on the world. That four days in February 1994 was one such weekend.

What made it so? In the span of four days I was presented with a large volume of research - that contradicted much of what I'd been taught in school. This was, at first, unsettling - but the "scientist" in me decided that you can't simply discount the literature and that if it was all about "being a better PT" then I better sit down and do some homework to understand how all these issues fit together. It pushed my "comfort zone" ... and started me down a path that changed not only my career but my personal life perspective as well. 

When I was last in this neighborhood, we were discussing the amazing adaptability of the human machine. Incredible as it may sound, human physiology and anatomy will consistently adapt to the world - and if unable to do so, will give us warning signs (such as pain) and then show us that it is unable to do so - by way of injury. 

Lest we forget, the body aims for homeostasis - which is, implicitly, "balance". So at any given time, we are in homeostasis and thus always "in balance" relative to the demands on the system at that given point in time. Homeostasis is a wonderful thing. Our cellular mechanisms are constantly seeking homeostasis. We are always trying to find a balance - between stimulus and response, between training and recovery.

But here's the twist ...

To live on planet earth, humans are constantly adapting to the demands of their surroundings. As I am always saying (to anyone who will listen) - Form Follows Function. Our anatomical form evolves depending upon the functional demands that we face. Throughout the evolutionary process, the human form has changed to allow it to better adapt to the world around it.

Let's take a look at a few basic examples. An astronaut traveling to the moon adapts to the inherent decrease in gravitational force by having less muscle mass and a decrease in bone density. Why? There is no functional need for these - and thus the body adapts accordingly. On return to earth, there is a gradual return of bone density and muscle mass. Why? Because there is a functional demand placed on the body - and it adapts accordingly. Form follows function. Along the same lines, the average sedentary American, the "couch potato" if you will, has become very finely tuned anatomically to deal with the imposed demands of "couch-potato-dom" - a perfect slouch into the big puffy couch and very strong thumb musculature for the use of the TV remote!

I am about to get another year older. I find that every so often, something during the day will trigger a myriad of flashbacks from days of yore. Case in point - do you remember the TV game show “The $10,000 Pyramid”? In it, a team member would give clues to his/her partner to describe a topic or phrase. The goal of the partner was to guess the topic. If you worked your way up the pyramid, you could win $10,000. Ahhh yes , the things that we remember ...

Before we go any further, I can guarantee you that $10,000 isn't at stake in this article! But, today I present to you “The Triathlete's Pyramid” - and I will be your host. Who needs Dick Clark anyways?

In the first round, your partner shouts out - “aerobic system, maximum VO2, heart rate monitor ...”.

Physics. For many people, just the mention of the word gives them high school flashbacks – or nightmares. Love it or hate it, physics provides us with the foundations for our understanding of the world – even the world of the endurance athlete. 

Let's take a common discussion topic. Athlete A, a relative newcomer to the sport, has done a few sprint triathlons and now wants to do an Olympic distance event. Athlete B, a seasoned triathlete, is finally ready to go after that first Ironman. How do either of these athletes “move up” and “go longer” successfully?

Before we get our emotions involved, get our mitochondria in a knot, and start the heated debate about lactate threshold, heart rate monitors, and the need for aerobic training, let's look to physics for a guiding light. If it is good enough to define nature, it's probably good enough for your neighborhood triathlete. Maybe, with any luck, Newton was a triathlete ...