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Health Is Not Defined by Fat and Skinny. Test These Metrics Instead.

A proper fitness assessment considers aerobic health, muscular strength and endurance, flexibility, and body composition. Here's how to test these variables in yourself.

By Cari Shane
Mar 19, 2022 5:00 PMMar 21, 2022 2:13 PM
(Credit: Andrey_Popov/Shutterstock)


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Your level of fitness isn’t limited to the number you see on your scale or the size of your biceps. Research suggests there are four main indicators that together assess our fitness: aerobic health, muscular strength and endurance, flexibility, and body composition.

Remember, being thin isn’t the same as being healthy. In fact, a study released in 2008 suggests that you can be fat and fit and thin and unhealthy. The researcher behind it found that 1 in 4 people has an underlying condition, like high blood pressure. And this applies to many people who look great to the naked eye, and often stay that way no matter what they eat. This unhealthy bunch — those who eat donuts for breakfast, avoid vegetables and seldom consider what they put in their mouths — have earned the moniker “skinny fat”; others suggest this group suffers from  “normal weight obesity” (NWO).  A 2015 report suggests that many people with a seemingly normal BMI (body mass index) have a significantly higher risk of metabolic problems and death despite the way they look.

So, how healthy are you? The following metrics can help tell you.

Aerobic Health

First, figure out your resting heart rate. For your heart to be considered healthy, the typical adult’s resting heart rate should fall between 60 and 100 beats per minute. Check your pulse by placing your index and middle fingers (not your thumb) on either the side of your neck or the inside of your wrist. Set a timer for 15 seconds and count the beats. Multiply the number of beats by four.

Second, test your heart rate while doing an aerobic activity. Also known as your target heart rate, the numbers should different depending on your age. While a 25 year old’s target heart rate falls between 98 and 166, a 55 year old’s should be between 83 and 140. Harvard Health, a division of Harvard Medical School, suggests taking the step test which involves walking up five flights of stairs. Once you’ve hit the fifth floor, rest or sit for one minute, then check your pulse using the same method described above. Harvard Health suggests checking your rate against the YMCA standard. On this rating chart, a healthy 36 - 45 year-old man’s pulse will be 90 or lower and a woman in the same age category should come in at 96 beats or less. 

Muscular Strength and Endurance

The American Council on Exercise (ACE) says, “There are two types of muscular fitness assessments: muscular-endurance tests, which assess the ability to resist fatigue; and muscular-strength tests, which assess the maximum amount of force an individual can produce in a specified number of repetitions.”

You can test your muscular endurance with a push-up and sit-up test. In the push-up test, you’ll need your chin to touch the floor. Count how many push-ups you can do. If you are a 35-year-old woman, your target goal is 19 push-ups without stopping; if you’re a man of the same age, you should be able to do at least 21. While the Mayo Clinic considers the push-up test more accurate than a sit-up test, you can try this test too. “Good fitness” for a 35-year-old woman means doing 30 sit-ups (or crunches), or a man of the same age should be able to do 40 in one minute.

For muscular strength, you can test in a variety of ways. Common methods include a bench press or leg press, arm curl, pull-down, knee extension and/or knee curl. You’ll likely need a personal trainer to help you assess your muscle strength.


According to the University of California Davis’ Health Sports Medicine division, flexibility is an indicator of an individual’s overall health profile because it tells the story of joint, muscle and tissue health.

  • Joints: A healthy joint, like the hips and knees which bear a lot of your weight, gets lubricated, or oiled, when there’s a good blood supply. If you’re inflexible, joints may not be getting the nutrients they need.

  • Muscles: Inflexible muscles put more pressure on other muscles. That can lead to muscle fatigue which, in turn, could lead to joint injuries since the muscles are too tired to do their job. The hamstring muscles, for example, keep the knees stabilized. Weak hamstring muscles could increase the chance of an ACL tear.

  • Tissues: An inflexible person may find that they suffer from a lot of differed pain. For example, someone might get tendinitis of the knee because their calf muscles are so tight.

While age may play a role in how flexible you are, regular stretching can help lessen the natural decrease in flexibility that begins in our 30s and 40s. It’s important to note, too, that men typically lose their flexibility faster than women.

To check how flexible you are, do the sit-and-stretch test which measures flexibility in the back of your legs, hips and lower back. Grab a yard stick and sit down with your legs out; line up the bottom of your feet with the 15-inch line on the yard stick. Reach forward three times for at least one second and record your farthest distance. Those who are 65-plus should be able to reach from the 17.5- to 15.5-inch mark, depending on gender; a 25 year old will be considered flexible if their reach extends to the 19.5- to 21.5-mark.

Body Composition

We’ve all heard about different body types or shapes — the pear, the apple, the hourglass and the rectangle. It’s believed that the apple-shaped individual, the person who carries more weight above the hips, has a greater chance of heart disease and diabetes. According to the Mayo Clinic, women with a waist circumference of 35 inches or more and men with waist circumferences of 40 inches or greater are at greater risk for these metabolic syndromes. 

To check your numbers, simply measure your waist with a measuring tape just above the hipbones.

Another way to measure your body composition is to determine your BMI. You can use a BMI calculator to check your score. Simply input your gender, age, height and weight and the circumference of your waist. If your BMI is between 18.5 and 24.9, you are considered to have a healthy BMI.

Remember, it’s not just one thing that makes you healthy. And it might be best to stop judging your book — and everyone else’s for that matter — by looking at the cover.

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