Welcome to my blog. In this blog we are going to talk about the difference between Isotonic contraction VS. Isometric contractions. What they are and how they make a difference.
There are multiple ways in which muscles produce tension. Training in these specific ways produce similar outcomes, such as increased strength, but also provide different benefits, such as improved muscle/tendon/joint health. Before we start, let us take a look at each type of contraction.
Eccentric
The muscle is lengthening as it contracts. For example, if you hold a weight in your hand with your elbow bent 90 degrees, then lower the weight until your elbow was straight, this is an eccentric contraction for your bicep muscle.
Concentric
The muscle shortens as it contracts. For example, perform the opposite as above. Start with your elbow straight and then bend it to 90 degrees. Your bicep has just performed a concentric contraction.
Isometric
Having a muscle contract, but the joint that controls it does not move. For example, same example as the eccentric contraction except the elbow does not move. There is tension on the bicep muscle and it still contracts, however, the arm doesn’t move.
Isotonic
The muscle contracts and the joint at which controls it increases or decreases while the muscle lengthens or shortens. (Eccentric/Concentric).
Muscles produce the most amount of force, or develop the most amount of tension, eccentrically. This is why most people can usually lower a heavy weight with control but struggle when pushing it up (for instance bench press). The more tension or force that is produced, the stronger the muscle becomes. Eccentric contraction (strengthening) is an effective way to rehabilitate a weak muscle following surgery. The benefits of eccentric exercises are due to increased collagen synthesis and tendon remodeling found during force variations. The drawback of heavy eccentric training is it is more likely to produce muscle soreness, both during and after exercises.
Another effective way to develop tension in a muscle is isometrically. Isometrics are typically considered safer after surgery as it is very controlled, and it can be self- monitored in the effort they are applying. There is a drawback, the strengthening effect is specific to the joint angle you are holding (typically about 15 degrees each way). Therefore, it is best performed at a variety of angles. An example is shoulder internal or external rotation. This can be achieved by standing in a doorway with the elbow bent and gently pressing into the doorway with constant pressure while not adjusting the joint angle. A lot of these examples are great after surgery or for seniors to benefit from slow tension contractions to strengthen their muscles in a controlled, slower way.
Concentric contractions develop the least amount of tension in the muscle. The upper extremities are performed using the muscle concentrically, for example lifting objects above waist or shoulder height. This is the way most people train in a gym or with a personal trainer, however, it is very functional, but you do not receive all the strength gains you may be anticipating.
There are benefits to each contraction. We use all the above depending on your goals. In your general fitness and exercise routine, you may use one contraction over another, again, depending on your fitness goals. All in all, each type of muscle contraction is important for overall function. The timing as to when you use a specific contraction can be particularly important, especially when recovering from injury or surgery.
If you would like to talk with us and learn more or if you feel you would benefit from some instruction and structured care, let us know give us a call or e-mail us and we will be glad to help.
Thanks again for reading my blog and I hope it helps you to know the difference between the contractions and how they help. Knowing the different contractions will benefit you when designing your own fitness plan.
Take care and I hope you live a happy and healthy life.
Darren
Harmony Shift 