What The Hell is Fitness: The Definitive Guide

*not* the fittest man on earth

We’re all trying to “get fit” or “get healthy” and I’m always workin’ on ma fitness, myself, so I wanted to broach the subject of What the hell IS Fitness?

Everywhere you look, you see the word “fitness,” and there seems to be this pervasive idea that endurance = fitness; That the guy who wins the marathon at the olympics is the fittest man in the world.

But have you SEEN guys who win marathons? They look like death!

Take this guy, for instance. Dude might have won the marathon at the olympics but he wouldn’t be able to deadlift his mother if she was rigid and shaped like a barbel! (Click here to Tweet this quote!)

Would you want to look like this?

Girls, do you want your man to look like this? I doubt it, ’cause he’s gross.

So if endurance isn’t the end all be all of fitness, what is? Endurance is part of the answer, but not the whole answer. In order to be considered “fit,” you must have endurance and you must have a lot more! Think about You, but fit.

  • What does that look like?
  • What would you want to be able to do?
  • Who do you want to be?

Everyone Has Their Idea

If you don’t know what you want to do/be and can’t come up with any reason to be fit, check out Steve Kamb’s Epic Quest of Awesome for some inspiration. His list may not be all physical activities, but being fit changes your outlook on life and opens up all kinds of wild and epic opportunities.

What is fitness to you? – here are some of the responses that I especially liked.



It comes down to being able to do the things you want to do. Fitness means different things to different people, but we all know it doesn’t include feeling crappy!


Ultimately, fitness is an investment. – You will either pay for training, food, and a membership now or you’ll pay for co-pays, tests, and prescriptions later.

You get to pick!

Defining Fitness

Along with being a scientist, and fiercely committed to objectivity, I’m a CrossFitter. Much of the following definition of Fitness will come from Greg Glassman, the founder of CrossFit. Luckily, his ideas came from the scientific literature!

Side Note:

The following is definitely not an exhaustive list, and, as I know my knowledge pales in comparison to the collective knowledge of the crowd, I want you to chime in with what you would add to the following definition.

Now, the things that define Fitness fall into one of three categories:

  • General Skills
  • Physical Performance
  • Biological Metabolic Energy Systems

Just like you need to know what “winning” is in order to compete successfully, and you need to know what “success” in order to achieve it, you need to know what fitness is in order to reach for that goal effectively. So, to expand on the three categories of fitness:

1. General Skills

Most exercise physiologists recognize 10 general physical skills that can be developed in a human and they cover most all physical activity from getting out of bed to loading a pickup truck to high level competitive sports. They are:

  1. Cardiovascular/Respiratory Endurance – The ability of body systems to gather, process, and deliver oxygen.
  2. Stamina – The ability of body sys- tems to process, deliver, store, and utilize energy.
  3. Strength – The ability of a muscular unit, or combination of muscular units, to apply force.
  4. Flexibility – the ability to maximize the range of motion at a given joint.
  5. Power – The ability of a muscular unit, or combination of muscular units, to apply maximum force in minimum time.
  6. Speed – The ability to minimize the time cycle of a repeated movement.
  7. Coordination – The ability to com- bine several distinct movement pat- terns into a singular distinct movement.
  8. Agility – The ability to minimize transition time from one movement pattern to another.
  9. Balance – The ability to control the placement of the bodies center of gravity in relation to its support base.
  10. Accuracy – The ability to control movement in a given direction or at a given intensity.

There are many ways to improve fitness, but when you’ve broken fitness down like this, you can focus on improving a certain area with a certain kind of training.

Numbers 1-4 are improved through training – Hard workouts with barbells, intervals, sprints, triathlons, yoga, and the other things that improve performance by changing the structures of the body: Muscles, ligaments, and tendons.

Numbers 7-10 are improved through practice – Doing things that you are not great at in order to allow your body to make the necessary adaptations. These are the neurological changes that lead to being better at a thing.

Numbers 5 and 6 are improved through a combination of training and practice – Better neurological control of an improved set of muscles is a pretty rad situation to be in.

As far as most people are concerned, this would be a pretty thorough definition of fitness, but we’re only 1/3 of the way through this thing! If you need to, take a workout break and come back to finish!

2. Physical Performance

This is less scientific than the other two, but still very measurable. Basically, someone who performs better at a given task is more fit, regardless of the task. But being fit in one area does not necessarily translate to a higher level of fitness overall.

Fitness then, is about performing well at any task imaginable, whether it is something you are familiar with or not. You should be able to

  • run, jump, swim
  • ride, climb, push
  • pull, press, and play

In nature (not necessarily OUR nature) performance in an infinite number of random physical tasks will be required for survival, and those best able to handle what’s thrown at them will be the ones to survive.

They are more fit.

3. Biological Energy Systems

Varied exercise time domains will work all three pathways

When it comes to the metabolic engines we each possess, there are three pathways by which energy is transferred from the fuel we take in to the actions we take.

  1. The Creatine-Phosphate Pathway – lasts up to about ten seconds, and is required for the high powered, explosive energy output seen in things like olympic weightlifting, javelin throwing, and standing broad jump.
  2. The Glycolytic Pathway – lasts up to several minutes and is used in moderate-power, anaerobic activities like an 800 meter run or the first few minutes of any exercise that required more energy then resting.
  3. The Oxidative Pathway – is any aerobic activity. When you get breathing hard, it’s because your muscles used up the available oxygen in energy production and need more of it. Anything longer than a few minutes will fall into the Oxidative Pathway of energy production.

Varied training that will tax each of these energy production pathways will be the best to get yourself to peak general fitness. If you are a competitive weight lifter or marathon runner, you will want to favor one or two in order to focus your abilities.

Most people, however, are not trying to lift 1117 lbs. or win a marathon, so broad, general, and inclusive fitness is what you’re looking for.

  • Weightlifters and Shot-putters can be fatsos
  • Marathon runners can look like leathery skeletons
  • The Decathletes look like absolute badasses.

Don’t you want to be a badass?

How to Get Fit

Based on the above definition, the way to get fit is to work on getting better at everything right? You want to be more skillful, better at feats of strength, and good at short, medium, and long durations.

I’m not here, today, to take you from Silver to Gold in an olympic sport, discuss the minute details of exercise methodology, or help you drop that last 0.01% bodyfat for a bodybuilding pageant contest.

Here is an overview of the types of workouts you should be doing to get from where you are to a super fit version of yourself as quickly as possible.

1. Bodyweight / Plyometrics / Gymnastics

These movements range from “anyone can do it” to “holy shit! look what that dude just did!” Most of us will start with the former and progress towards the later. In this sections, we’re looking at:

  • Pushups, Air Squats (with no weight), Situps
  • Pullups, Dips, Muscle ups, Handstands
  • Handstand Walking, Gymnastics Flare
  • Any other creative movements you can think of

You can probably spend the rest of your life working on these and never stop seeing improvement in one area or another. One of the huge benefits of gymnastics type movements is their tendency to increase core strength, or midline stabilization, which spills over into every area of physical activity and athletic performance.

2. Cardio

Yes, I have written about doing too much cardio, but that doesn’t mean I’m against it all together. There are many benefits to be had from cardio of varying durations.

Some people actually like jogging.

I believe it’s jogging or “yogging.” It might be a soft “J.”

So…I don’t run for fun, but you can see some big changes in your metabolic engine in all three energy pathways when you do a wide variety of cardio exercises, including running, rowing, biking, swimming, and others.

  • Short sprints for the Creatine-Phosphate (CP) pathway – EX: 100 meter run – 10-15 seconds
  • Intermediate runs for the Glycolytic pathway – Ex: 200 meter swim – 2-4 minutes
  • Longer runs to activate the Oxidative pathway – Ex: 3 mile+ bike ride – 8-15 minutes

Each of these durations will vary from person to person as each of your metabolic engines are at a different level. Some people’s glycolytic pathway can only run for a minute and others can go hard for a few minutes before breathing heavy.

The CP and Glycolytic pathways are anaerobic (don’t use oxygen), and the Oxidative pathway is aerobic (uses Oxygen). It is important to train in both, so mix it up with your cardio in terms of both distance and intensity. If had to pick one or the other for you, I’d pick the anaerobic it has a much wider range of benefits, including increased fat burning.

3. Weightlifting

Let me be clear. When I say “weightlifting,” I am not talking about isolating muscles with a machine at the gym! I am talking about “weightlifting,” as in the olympic sport, not just the act of lifting a weight.

Weightlifting, the sport, consists of compound movements that call on a number of different muscle groups as well as neuromuscular control for technique, balance, and stability. The weight training movements I want to you look into are

  • deadlift – just ask Mehdi from Stronglifts
  • squat – Mehdi, again.
  • clean – videos from California Strength.
  • jerk
  • snatch – Ask Nick Horton

If you do just these five, you’ll be well on your way to being super strong with balanced strength throughout your body.

Why these?

The hormonal response from these multi-joint, compound movements has been shown to be much greater than with a work that isolates the muscles used and works them individually. The neuroendocrine response includes insulin-like growth factor, human growth hormone, testosterone (don’t worry girls, you will not get bulky), as well as a smorgasbord of others.

There is no need to the leg curl, calf raise, barbell shrug, lateral raises, or the curl machine, as all of these muscles and more are worked organically in the compound lifts plus you get the benefits hormonal effect.

This Entire Article in 100 Words

There are entire books, blogs, conventions, and graduate programs designed to teach you the finer points of working out, and this is not a “how to workout” post, so I will leave you with a great quote from Greg Glassman.

World-Class Fitness in 100 Words:

  • Eat meat and vegetables, nuts and seeds, some fruit, little starch and no sugar. Keep intake to levels that will support exercise but not body fat.
  • Practice and train major lifts: Deadlift, clean, squat, presses, C&J, and snatch. Similarly, master the basics of gymnastics: pull-ups, dips, rope climb, push-ups, sit-ups, presses to handstand, pirouettes, flips, splits, and holds. Bike, run, swim, row, etc, hard and fast.
  • Five or six days per week mix these ele- ments in as many combinations and patterns as creativity will allow. Routine is the enemy. Keep workouts short and intense.
  • Regularly learn and play new sports.

What Does Fitness Mean To You?

Why do you want to be fit? What is the big, hairy life goal that requires you to be your best? I want to hear form you in the comments. It’s one thing to know the “How,” but what’s your “Why?”

Did you like this post?

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(1) Kraemer, W. (2005). Hormonal Responses and Adaptations to Resistance Exercise and Training. Sports Medicine, 35(4), 339-361.

(2) Durand, R. (2003). BASIC SCIENCES: Original Investigations Hormonal Responses from Concentric and Eccentric Muscle Contractions. Medicine & Science in Sports & Exercise, 35(6), 937-943.


  1. Fantastic rundown and enumeration of the key aspects and dimensions of fitness.

    I’m always a fan of framing out the landscape and figuring out the topology map before diving into a topic. I think it helps paint the bigger picture, and to help choose where to spend more time.

    • grahamlutz says:

      Thanks, J.D.!

      I try to make these things as clear as possible so that we can eliminate confusion and focus just on those things that make a difference!

  2. Madeline says:

    I think my idea of “fitness” is what you touched on with “physical performance.” I don’t say you necessarily have to perform “well,” BUT my idea of fitness is to be able to do anything, anytime, anywhere. If you’re in Taiwan and want to do an 8 hour hike that the locals warn you against, you should be able to do it. If you’re at the park and a group of friends want to play kickball, you should be able to do it. If you’re at the lake and see a very enticing island a good ways away and you’d really love to swim over to it, you should be able to do it! Climb Kilimanjaro! Hike the Inca Trail! Go backpacking, not just camping! Being fit means the opportunities this world will present to you are ENDLESS! And that is really exciting! (-:

    • Graham Lutz says:

      Endless opportunities is right! I want to climb the million stairs to see that enormous seated buddha in Hong Kong!

  3. Great article that really sums things up concisely. My definition of fitness has come a long way since Crossfit and I now tend to shy away from breaking things down too much. It’s like approaching food as only made up of constituent nutrients. That can lead to some pretty messed up eating habits. Similarly, fitness should be holistic. Fitness here refers to ‘ability to move’, not reproductive fitness. Strictly, fitness changes with the environement. The biological definition can accommodate any reproductively successful individual, and in that case non-functional but pretty body builders with charm are more fit than shy decathletes who can’t win girls, sice the former is more likely to reproduce (in our current environment). They may not be healthy though.

    So…my definition of fitness now means health. Fitness as you discuss it here is really movement ability, an integral part of health but not all of it.

    Again, great article. It is nice to find someone saying what needs to be said without oversimplifying.

    • Graham Lutz says:


      I think the reductionist views that pervade most things related to health are pretty damaging, and you’re right that fitness is more than the ability to move. Part of what I wanted to convey is that Fitness is dependent upon the task at hand or the situational environment in which you find yourself – and I think that’s what you’re saying here.

      Thanks for coming by!

  4. The fittest man or women on earth is whoever wins the Crossfit games this year! I honestly can’t think of a better way to test overall fitness. Crossfit requires so many different skills. To look at the contrast between one event in the Crossfit games and another is to look at the contrast between black and white. No long distance, cardio over loader, will ever be considered “fit” in my book.

    • Graham Lutz says:

      I agree 100%! Being able to do the triathlon one day and clean 255# another day, and everything in between!

  5. OMG, this definition of being FIT is so complete Graham.

    Compare to my simple definition of “being in shape” you are so advanced talking about biological system.

    Totally agree

  6. Great article Graham! Such a comprehensive view on what it means to be fir, that it left me thinking.
    My whole life I’ve been addicted to the idea of being “fit” without actually giving a thought of what it all means. I love the distinction you made into three categories, it really comprises the whole spectrum of what it is to be fit (since nowadays it’s the only label given for people who want to achieve physical peak).

    For me I guess, besides the neat classification you just made, being fit is also a state of mind, mind-set, if you will.
    How so? I noticed that there are times where I’m near my peak at endurance, speed, power, agility, flexibility… and yet, I still sense that I can give more. That I’m not “fit” enough. That’s how I ended up doing workout programs like Insanity, and now I’m preoccupied with the idea of running a 5k under 16 minutes. Crazy right? For me, being fit I guess is physical and mental peak all together. You simple feel it. Oh, and being healthy is the most important part of it too, since without it, all is for nothing.

    • Graham Lutz says:

      Oh I agree 100% that the mental side of things is huge as well. You generally can give more in doing whatever it is you’re doing. It is rare that people are really held back by their body, but that their mind will not allow them to do what their body would be able to do.

      Mental fitness, then, is about being able to go to absolute edge of your physical fitness, and winning over those things that try to demotivate you or bring you down. Great though, Slavko!


  1. [...] It is, among other things, a pursuit of improving oneself physically, being better in terms of what fitness actually means. [...]

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