What’s the definition of fitness?

What’s the definition of fitness? What Does It Mean To Be Fit? Have you ever wondered what fitness really is? Is it a relative term, does it mean different things to different people for example? Does being fit mean you can run a certain distance in a certain time perhaps? Does it mean being a certain weight? In this article we will take an in-depth look at exactly what it means to be fit and how to measure your own current level of fitness.

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Defining Fitness

In order to understand what it means to be fit, we must first start out by defining exactly what fitness is. According to most dictionaries being fit generally means to be in good physical condition and good health. Thefreedictionary.com defines fitness as Good health, especially good physical condition resulting from exercise and proper nutrition for example. Whilst that may neatly summarise the state of being fit, it is a bit vague and does not adequately define what fitness actually is. Medical News Today offer a more comprehensive definition of fitness by splitting it into five key components, which we will now take a closer look at.

1. Muscular Strength

Muscular strength is what enables you to move, lift and carry. Whilst we may take our strength for granted in younger years, from middle-age onwards we start losing about 3% of our muscle strength every year. Hence, it is important to offset this natural decline with some sort of resistance training not just when it starts happening but throughout your life. Any sort of resistance training will do. You do not have to suddenly take up powerlifting.

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2.  Muscular Endurance

Muscular endurance is your ability to use your muscles over an extended period of time. It is not just athletes and marathon runners who need muscular endurance, we all need it in order to go about our day-to-day lives. Muscular endurance is associated with higher energy levels, better sleeping patterns and generally improved mood. The way to increase your endurance is to perform an exercise to failure, keep going even when you want to give up. It will become easier as your endurance gets a bit better after each time.

3. Cardiovascular Endurance

Cardiovascular endurance is your ability to keep going when your blood starts pumping and your heart starts thumping during demanding exercise such as running or cycling. The cardiovascular system, (your heart, lungs and blood vessels), work to fuel the body with oxygen during intense exercise. Running is one of the best ways to increase your cardiovascular endurance but any form of aerobic exercise will be beneficial.

4. Flexibility

Many people do not think of flexibility as a component of fitness and assume that becoming inflexible is part of the natural aging process. In a way, it is but, as with any of the other components of physical fitness, you should try to offset this as much as possible by doing flexibility exercises such as yoga. Flexibility is a crucial component of your overall fitness. Without it your joints would become stiff and your range of movement limited.

5. Body Fat Composition

Finally, body fat composition refers to the amount of fat you are carrying at any given time. There are two main ways to test your level of body fat, either using calipers or specialised scales. Calipers measure the thickness of a fold of your skin to gauge the average amount of fat. Specialised electronic scales use a small electrical current that runs through your body to measure the amount of resistance from body fat. Neither method is one hundred percent accurate but they both give a fair idea of the amount of body fat you are carrying.

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How to Accurately Test Your Level of Fitness

Some gyms offer specialised tests that measure all five components of fitness discussed above. The tests are usually inexpensive and brief. You will normally get a full breakdown of your statistics at the end of the test. You can then keep this and compare it with future test results. Experts recommend regularly testing your fitness levels every couple of months or so. If your local gym offer such tests, they are well worth doing on a regular basis in order to keep a check on your fitness levels and set appropriate goals for the future perhaps. But what if your gym doesn’t provide such tests, how else can you keep a check on your level of fitness?

Well, the first thing to remember is to pay attention to how you feel generally. Can you walk up and down stairs easily enough? Does dashing for a bus get you blowing? Can you still bend down and tie your shoelaces? It is important to be honest with yourself. Notice how these questions are gauging the different components of your overall fitness.

Now, if you would like something a bit more consistent, so that you can measure your results and strive to improve them over time perhaps, you could try devising your own fitness test based on the five components of fitness discussed above. In order for the test to be effective and accurate you will have to standardise both the exercises and the recording of your results.

We will now look at some examples of exercises you could and should incorporate into your fitness test.

Test One – Muscular Strength

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Grip strength is a good indication of not just the muscles in your hands, wrists and forearms but your overall body strength. Gyms incorporate grip strength into their fitness tests by using a handgrip dynamometer but this is something you can easily replicate with a 20Kg plate. Just hold the plate between your thumb and fingers for as long as possible. Make sure you use the same plate each time and make sure you record the exact time you are able to hold it for.

Another way of testing your muscular strength at the gym is with your one rep maximum. You can test this on different exercises but for the purposes of your fitness test pick one big compound exercise and use that as your standard measure. Bench press is ideal. Basically, you start off with a few warm up sets then load on what you think is near your maximum possible lift and do a single rep. If you succeed, add a small biscuit weight either side and try again. Keep going like this until you physically cannot lift the weight. It goes without saying that you should always have a training partner with you when trying for your one rep maximum lift. Your one rep maximum is the last lift you successfully complete unaided by your training partner.

Estimates vary as to what is a good weight to be able to lift. It depends on a number of factors like age, genetics and body type, for example, which renders any ballpark figures pretty much useless. Instead of comparing yourself to arbitrary averages, the only comparisons you need make are your current test results with your last test results. In order to try and offset the natural decline in strength that comes with age, you should aim to be a bit stronger each time you test your fitness which, as we have suggested, should be every couple of months or so. You won’t always make such gains but in trying at least, you will be balancing out the natural loss of strength that comes with age.

Test Two – Muscular Endurance

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You do not need heavy weights to test your level of muscular endurance, bodyweight alone is enough. However, that does not mean the tests will be any easier. Muscular endurance is what separates the winners from the also-rans.

The first thing to do is to pick a bodyweight exercise. Push-ups are ideal but you could choose sit-ups instead. Just do as many as you possibly can and record the number you fully complete in good form. Do not cheat yourself. Stick to proper form and do not give up until you are completely exhausted. Another way you can test your muscular endurance is with plyometric exercises such as star jumps. Again, just do as many as you can and record your final number. The most important thing to remember is to be consistent. It has to be the same exercise each time, performed in exactly the same way, so choose one you like.

As with muscular strength, there is no meaningful average to compare yourself against when it comes to muscular endurance. Again, you want to try beating your last test results each time you retest your fitness level.

Test Three – Cardiovascular Endurance

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There is one simple way to test your cardiovascular endurance – get on the treadmill or hit the pavement but first you need to establish a perceived exertion scale that you will use during your run. The original such scale was created by Gunnar Borg and rated exertion on a scale of 6 to 20. It was later modified and adopted by medical practitioners to help diagnose certain conditions and ailments but perceived exertion scales are still used widely in sports to this day. For the purposes of your scale, we will keep it relatively simple:


Do your run then note down, according to the scale, how much you feel you exerted yourself. You decide where your efforts were on the scale, it is a self-assessment. Just be honest with yourself. There are no extra points for scoring yourself lower than you were actually feeling. As your fitness improves you should find your perceived exertion reducing.

The reason a treadmill is better than the pavement for the purposes of testing is simply that you are able to record exact figures and replicate conditions for your next test. You can run for a set time and record the distance you covered and your perceived exertion. Or, you can run for a set distance and record the time it takes you and your perceived exertion. The armed forces generally use a set distance for this kind of test because it is likely to be a truer reflection of your overall cardiovascular endurance. Two miles is about average and anything under ten minutes a mile would be considered good. Under eight minutes a mile would be considered above average and under seven minutes a mile would be considered excellent.

Test Four – Flexibility

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There are a multitude of exercises that you could choose from to test your flexibility but you need to have some way of recording your level of flexibility for the purposes of your test results.  An easy way of achieving this is to sit on the floor with your back to the wall and your legs open scissor-like. Put a large book in front of you then simply lean forward and push it as far as you possibly can with the tips of your fingers. Next, stand up and measure the total distance you have managed to push the book from the wall.

You can choose an alternative exercise but, just remember, you have to be able to record the result somehow so that you have something to compare it to on your next test. One other thing to consider is clothing. When you are doing flexibility tests clothing can be quite restrictive, so make sure you wear the same clothes each time.

Test Five – Body Fat Composition

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There is no point trying to measure your body fat percentage with anything other than calipers or specialised scales. You can buy either quite cheaply online these days. Just remember, you usually get what you pay for so if you are serious about your fitness tests, it is probably worth investing in quality products that are likely to be more reliable and last longer.

As a general rule of thumb, the American Council on Exercise quote the following averages for body fat percentages:


If you don’t like the idea of measuring your body fat with calipers or scales, you can alternatively record your Body Mass Index (BMI), which is quite easy to work out. It is simply a calculation of your weight in relation to your height. There are two formulas to calculate BMI, depending on whether you use metric or imperial measurements.


Weight(kg) / Height (m)2 = BMI

Using metric as an example, if you are 1.65metres tall and weigh 72kg, your calculation would look like this:

72kg / (1.65)2 = 26.45


[Weight (lbs) / Height (inches)2] x 703 = BMI

Using imperial as an example, if you are 5’7 that equates to 67” tall. Say you weight 150lbs, your calculation would look like this:

[159lbs / (65”2) x 703 = 26.45


The most important factor in testing your fitness is consistency. You should complete your tests every couple of months using the same equipment and exercises at approximately the same time of day. Never try to remember your results but instead record them straight away. You can use a notepad, your phone or a spreadsheet, whatever works best for you.

Now Go Get Fit!

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Now you know what fitness is and how to test how fit you currently are, it is time to start striving to improve your fitness levels. Joining a gym is a great idea but it is not the only way to get fit. Swimming, cycling and brisk walks will all do much the same job. At the very least, just start trying to be more active day-to-day. In a few years time your older self will thank you for the effort you put in now. Just remember, if you haven’t exercised for a while or you have any underlying health conditions you should think about consulting a doctor before embarking on any sort of fitness program.

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