The Three Compartments of Fitness

When I think of my fitness level, I compartmentalize it into three categories.  My goal then is to fill (improve) all 3 compartments simultaneously.  If one of the compartment is lower, then I fill it twice as much until it is as full as the others.  Any guesses what the 3 compartments are?

We’ll talk about it, but before we do, lets look at fitness in general.  How do we define fitness?  The model that makes the most sense to me is what is a person’s work capacity?  Look at the graph below and you’ll see a plot with power on the ordinate axis and time on the abscissa.  If we were so inclined, we could determine the power of every activity we do and plot this against the time it takes to do those activities.  The area under the line (the integral of the function) would be equal to work capacity.

We can see then that if we increase how much power we can produce and how long we can produce that power we increase the area under the curve.  This means we have greater work capacity.  This is a slick definition, and I find it very useful.

Work Capacity

So, what then must we do to increase our fitness (i.e. our work capacity) following this model?  I suggest that it isn’t any ONE thing, but that it is the 3 things I mentioned before.  Those three things are:

  1. Strength
  2. Skill
  3. Conditioning


Is your body conditioned in such a way that you are able to move quickly and accurately no matter the load or the duration of the effort?  I may be able to move a fair amount of weight at low volume, but what happens when I have a heart rate of 180+ bpm?


Being a skilled mover means a couple of things to me:

  1. I understand how to place my body into the correct positions so that I am efficient and I don’t get hurt
  2. My positional awareness and efficiency allow me to be more effective because I don’t have to rely solely on my strength

Skills are important, and can make up for a lack of raw strength in almost all areas


Muscular strength both in the slow twitch and fast twitch fibers is a benefit in every way possible.  Let me make the distinction here that I am NOT talking about BIG muscles or hypertrophy.  It is possible to be incredibly strong without being a body builder.  Strong muscles are more flexible, they’ll help keep joints safe, and my belief is that they are necessary for optimum health and fitness.

What areas are you lacking in?  There is overlap in these three things, but to really move fitness forward I believe we must develop these three categories evenly over time.  If you’re like me, you have some preferences between the three (I’d rather do strength than conditioning).  But to your best ability fill up your weak category.

A couple of bonus categories that’ll take you from average joe to superstar:
– mobility, do you have full range of motion at every joint?
– mental, do you push yourself to that uncomfortable place even when you don’t feel like it?

The Oboard Says…

“Hells Bells”

20 Minute AMRAP

200m Suitcase Carry (1 arm farmer)
10 Goblet Lunge (each leg)
200 m sprint
10 KB Snatches (sub 1 arm alternating kb swings)

Posted by: Stets