There are tests you can take that, depending on the results, can be indicators if you are unfit or not. Specifically they include:
Body Mass Index (BMI): BMI is a comparison of body weight to height. Both are factored into a formula to come up with a number. Depending if you are above or below the ideal BMI indicates if you are fit or not. Most BMI calculators consider a normal weight for your height if your BMI is 18.5 to 24.9. Anything over 24.9 is considered overweight; anything under 18.5 is underweight. A reading over 30 indicates obesity. While BMI is an indicator, it is not the only indicator.
Heart Recovery Rate: How fast your heart rate returns to normal after exercising. Before you stop exercising, take your heart rate. Take your heart rate again after resting for one minute. It should drop by 20 beats per minute or more in that first minute after you stopped exercising. It should continue to drop at about that same rate for each minute afterwards until it reaching your resting heart rate. If you have a slow heart rate drop, it could indicate that you are unfit.
Resting Heart Rate: Unfit people generally have a higher resting heart rate because the body has to work harder at rest than someone that is fit. A normal heart rate should be in the low to mid 70’s beats per minute. If your resting heart rate is above 75, it could indicate you are unfit.
Cardiovascular Strength: This measures the fitness of your heart and lungs. It is a simple test. A fit person can walk up three flights of stairs and be able to carry on a conversation at the same time. Unfit persons need to stop part way to catch their breath and likely be perspiring.
These tests are just four of many fitness tests available. Remember, results from each test are just indicators of fitness. Failing one test may not mean you are unfit, failing two or more could be cause for concern and an appointment with your healthcare professional, is recommended, for more in-depth tests of fitness level and overall health; and can prescribe an exercise regimen and diet that will improve your level of fitness.