Night Classes Now Available. Personal Training Classes

Not Interchangeable

Many people mistakenly use the terms flexibility and mobility interchangeably. Although flexibility is a component of mobility; mobility and flexibility are different.

Think About It

Everybody knows the words mobility and flexibility. Take a moment to think about these two words and define them before you continue reading. Seriously, stop and think. Flexibility is the ability of a muscle(s), as well as other connective tissue (ligaments and tendons) to lengthen. Mobility on the other hand is the ability of a joint to move actively through a range of motion.


Flexibility is passive. It’s a person’s ability to move their connective tissue with the help of another person or tool, while their muscles passively allow the movement to happen. Flexibility means the muscles are and joints are stretchy and pliable. Flexibility is important because when your body is restricted by inflexibility, and you can’t move through your natural range of motion. This restriction may also cause pain to occur. That means that our everyday life activities like getting out of bed, sitting at the kitchen table, bending down to pick up a book, or even reaching for a cup in the kitchen cabinet can become more difficult.


On the other hand, mobility is our ability to take our body through a range of motion, before being restricted by the limitations of the joint itself and/or limitations in flexibility. Mobility is having strength within your flexibility. Mobility is essential to our overall quality of life, especially as we get older. Our ability to move without restriction or pain means that we can comfortably perform daily activities with ease. If your body isn’t able to move through its natural movement patterns, you will be more susceptible to injury.

Test Your Flexibility

Lay on your back and loop a resistance band around your ankle. Use the other side of the band to pull your leg as close to your trunk as possible, if the length of your tissues allows, you’ll be able to pull your leg all the way down and grab hold of your big toe. If the muscles, ligaments, and tendons are shorter, you may only be able to reach your shins or knees, which is a sign that you lack flexibility, at least that you lack flexibility in your hamstrings.

Test Your Mobility

To measure your mobility, stand up and try to rotate your shoulder to fully extend your arm straight over head. If you’re able to move your arm and shoulder this way freely, your shoulder is mobile. If not, it’s a sign of a lack of mobility. In this example, instead of using a resistance band to move your connective tissues, you’re actively controlling and moving your own body without added resistance or assistance.

Personal Trainers

A qualified personal trainer must know the difference between flexibility and mobility. Fitness professionals need to know what is and is not, a functional range of motion for each joint. Also, fitness trainers must know and understand the principles of flexibly and how to increase it. Too often, trainers know little to nothing about the importance of flexibly and its benefits to their clients. That is why at NPTI of Arizona, we have dedicated a class for this purpose. Click this LINK to learn more about PNF Stretching.

By clicking the "Accept" button you are confirming that you are agreeing to our Terms & Conditions, Privacy Policy and to our use of cookies for a better browsing experience.