Isometric Exercises Vs. Isotonic Exercises

What is the difference between Isometric and Isotonic exercises? 

Both are critical components of any exercise program, however isometric exercises are growing in importance. 

Isometric Muscle Contraction:  The contractile force is equal to the resistive force, thereby producing no visible change in muscle length.  This type of muscle contraction is important because it dynamically stabilizes the body and places very little stress on the body’s joints.  An isometric muscle contraction stabilizes a limb from moving in an unintended direction: for example, the adductors and abductors (in the thigh) stabilize the leg from moving too much to the side during a Squat.  Another example of an isometric muscle contraction is the Plank or any variation of a Plank.

Isotonic Muscle Contraction:    Contractile and resistive force are produced and movement is visible through a given range of motion.

  • Eccentric Phase – The muscle action occurs when a muscle develops tension while lengthening.  This phase is known as deceleration, or lowering the weight during a resistance exercise.  
  • Concentric Phase – The muscle exerts more force than the resistive force, thereby shortening the muscle.  This phase is known as acceleration, or lifting the weight during a resistance exercise.

In conclusion, while an effective exercise program incorporates both both isometric and isotonic muscle contractions, it is also critical to note the importance of form – always be aware of your form and maintain good posture during all exercises to prevent injury.

Be Active, Be Healthy, Be YOU!

About rrluthi

Certified fitness expert with a passion for educating and empowering people of all ages (young "kiddos" to the active aging "baby boomers") about the benefits of adopting and maintaining an active, healthy lifestyle, preventing injury, and feeling good. Proven strengths applying cutting-edge fitness/wellness concepts and research through roles as a health coach, fitness trainer, group exercise instructor, and rehabilitation aide—in addition to promoting these concepts in a more systematic way through blogging and social media, community outreach, and corporate wellness program facilitation.
This entry was posted in Core Strengthening Exercises, Daily Workout and tagged , , , , . Bookmark the permalink.

1 Response to Isometric Exercises Vs. Isotonic Exercises

  1. Dan says:

    Hi Robin, great article. I would be intrested to know your thoughts on isokinetic training. I have always had trouble explaining its practicality, especially when dealing with power lifters and injury prevention.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.