How Fitness Works: Fitness & Adaptation

Do you ever sit around and wonder how something works? I know I do, because I’m a huge nerd that loves to know what makes things “tick”. In 2016 I’m doing a special series called “How Fitness Works”, where I’m going to explore how different things related to health and fitness…well…work! You can find all the articles in this series by searching for article tag HowFitnessWorks on this blog.

Welcome back (or welcome to the blog if this is your first time)!

Today we’re going to be talking about two big ideas in the development of your health: fitness and adaptation. These words get tossed around a lot, not just in the gym but in other disciplines like biology or zoology. It can be hard to pin down what each concept really means, so lets figure out how it works!


The good ol’ dictionary has a few definitions for fitness:

a. the condition of being physically fit and healthy.

b. the quality of being suitable to fulfill a particular role or task.

c. an organism’s ability to survive and reproduce in a particular environment.

If you ask a “gym-bro” about fitness, they’re probably going to talk about the first one, and most of us who regularly workout probably agree that the baseline definition we care about is related to our physical health. But the interesting part is that the other two definitions expand on this concept in a way that we can use to better understand why it is we need to be physically fit in the first place. Definition b lets us apply our general idea of being fit to specific tasks, such as lifting weights in a certain way or running from zombies (they’re coming!). Adding definition c into it expands the idea further so that not only are we training for the gym, we’re also training for life in general.

Many modern fitness programs, CrossFit among them, focus on functional fitness because this focus meets all three criteria of the definition we’re working with for being fit. Training for a specific sport, Baseball for instance, will make you better at that sport, but rarely will skills in a single sport translate well into a survival setting. Athletes are, generally, more inclined to do well in those situations by virtue of being more fit, but when you focus on general fitness rather than specific fitness in your everyday training your chances of survival when the aliens finally invade skyrockets. Nature favors the generalist.


Back in our friendly dictionary, we only have one relevant definition of adaptation to look at:

a change, or the process of change, by which an organism or species becomes better suited to its environment.

The general definition here applies most to the survival of an organism within the world at large and how it develops the ability to, ya know, not die. Examples might be a species of rabbit that, over many generations, slowly but surely favors offspring with longer hair in colder environments. Why? Because the shorter-haired rabbits are more likely to freeze to death before they have baby rabbits (rabbitlings? rabbit-seeds?). Nature plays for keeps!

In your lifetime you also can go through adaptations that make you better able to survive the day to day world. While true biological evolution takes hundreds of generations to manifest, an individual organism (such as you) can make physical changes in their lifetime which increase their survival rates. Becoming stronger, faster, more knowledgeable, or more emotionally tough are all examples of adaptations to stress that, in turn, make you more likely not to die.

Where do they meet?

Adaptation over time is the way that organisms become better able to survive in their environments, which is directly copied from the definition for fitness we talked about earlier. Exercise and stress, as long as they’re applied to you in a smart way, help you adapt to better handle the exercise or stress. You can see this as you sprint to become faster, as you lift ever increasing amounts of weight, and as you better manage your mental state when sh*t hits the fan in your life. Training and experience are what help cause the adaptations towards better fitness.

In the first few weeks of training, your body is going through a phase where it gradually begins to learn to condition itself to your workouts. It starts to set neurological connections to movement sequences, making you better at doing whatever it is you’re doing. Sometime around 3-4 months of the same workout, though, you start to see diminishing returns because your body and brain have functionally adapted to the workout. This is why variety is important in training, so you can keep forcing your adaptation response to stretch and grow your capabilities.

And we’re done! Join me next time where I’ll blow your mind with fitness facts from function to form.