What Is This Thing Called “Fitness”?

A quick google search of the term “fitness” will give you this definition: “The quality of being suitable to fulfil a particular role or task”. Thanks Google, but if I can run a marathon why can’t I lift really heavy things? Does that mean I’m not fit?


That’s because fitness can be broken down into components. Four, to be exact. Each is trained in different ways and offers different benefits for your body. It’s easy to get bogged down in the details, so read on for my quick guide to this thing called “fitness”.

  1. Aerobic Fitness

Put simply, aerobic fitness is endurance. It’s the ability to do a task for a long period of time at a sustained rate. You train this component of fitness if you go for an afternoon run or bike ride. As you’ll find with the other components of fitness, your aerobic fitness will build up over time. No one runs a marathon overnight.

  1. Anaerobic Fitness

Just in case you haven’t figured it out yet, anaerobic fitness is the opposite of aerobic fitness. It’s the ability to exert a high amount of energy over a short period of time. Activities that use anaerobic metabolism (hence anaerobic fitness) are often power based. Examples of these are sprints, or the latest trend of high intensity interval training.

  1. Flexibility

I’ve long since accepted that I’ll never be able to touch my toes. Nevertheless, I persist with stretching exercises in the hope of improving my flexibility. To minimise injury risk, stretches are always best completed after the body is warmed up, so after you have already completed some exercise. Even completing the relatively basic task of picking something up off the floor is made easier with increased flexibility.

  1. Muscular Endurance and Strength

This last one is a favourite of the gym junkie. Typically it is trained using resistance training methods, and makes lifting things a lot easier. You don’t have to go to the gym and lift really heavy loads though. While this may increase strength at a faster rate, recent research has shown that lifting lighter weights repeatedly can lead to significant strength and endurance gains.

So there you have it. Include these 4 things in your fitness program and you’ll be placed in good stead to a healthier, fitter, you.


Darcie Rehbein

Product Specialist

Darcie Rehbein is part of our Sports Scientists and Product team. Currently, a second-year clinical exercise physiology student at Queensland University of Technology. Darcie has swimming and AFL sporting background. She is interested in injury prevention and rehabilitation.