Did you know there are 3 different types of strengthening exercises also known as the 3 I’s of exercise? Most people only know about one and only perform that one when training.
But as a physical therapist, I will have patients perform all 3. These exercises are named Isometric, Isotonic, and Isokinetic.
Isotonic
The most common and the type most people will do day to day. Isotonic means “same tension or tone” or weight. So going through an exercise for 10 reps your weight does not change. For example: Bicep Curls.
To improve strength of muscles, isotonic exercises are performed. This type of exercise also improves bone density reducing osteoporosis.
Other Examples:
- squats
- bench press
- calf raises
There are no shortage of these exercises and I am not able to list them all. Check out my posts of my favorite upper and lower body exercises for more examples.
Isometric
Commonly used following surgery. Isometric means “same length”. The muscle is contracting but not going through a Range of Motion or the joint is not moving. For example: quad sets.
Isometrics are usually the first strengthening activities you can do following some surgeries. I will use them after knee or shoulder surgeries. These can also be used on all muscles.
The strengthening occurs without damage to the joint or muscles if they are healing.
Other Examples:
- Wall sit
- Planks
- 6 way shoulder
People can perform these activities with little or no equipment.
Isokinetic
Isokinetic is the least common in fitness and rehabilitation. These exercises are most commonly performed in rehab settings and for research purposes.
Isokinetic means “same speed”. The muscle is going through the motion but the speed at which the muscle performs does not change. For example: using a metronome to keep the same pace with any activity.
There are special machines are used to help maintain a specific speed during an exercise. Check out this video here of someone using an isokinetic machine.
These are the 3 I’s of exercise: Isotonic, Isometric, Isokinetic.