Eccentric exercise explained by Professor Ken Nosaka

 

 

This video is Part 1 of 2. Watch Part 2 (Eccentric exercise workout with Professor Ken Nosaka) here.

Transcript

Hi, my name is Ken Nosaka. I’m a Professor of Exercise and Sports Science in the School of Medical and Health Sciences at Edith Cowan University. I have been studying eccentric exercises for 25 years.

What is eccentric exercise?

Eccentric exercise is an exercise mainly consisting of eccentric contractions.

Eccentric contraction is contracting, when the muscle’s lengthening. So eccentric exercises include descending stair walking, or sitting down into a chair very slowly, or using this kind of object, lowering this kind of object very slowly. In this case this contracting muscle is stretched. This is eccentric contraction, that’s why eccentric exercise is exercise consisting of a lot of eccentric contractions.

Generally speaking, eccentric exercise is less metabolically demanding, for example when you are going down stairs it is much easier than going up. So it is less fatiguing exercise. Or if you are classified as obese or overweight, maybe you have more burden on your body, so it is easier for you to go down than go up. In that case, eccentric exercise is very beneficial and easier to perform.

Health benefits of eccentric exercise

Eccentric exercise can affect the whole body. Initially resistance training with eccentric exercise can stimulate the muscle. The main thing is that muscle mass and muscle function are key for your health.

For example if you lose muscle mass, that can result in decreased insulin sensitivity, then you can become more susceptible to diabetes and also it can increase heart diseases and also it can decrease bone mineral density, then your bones get weaker. Also it can maybe affect your mental ability. Your cognitive function can decrease because of a loss of muscle function. So muscle is the key.

We need to maintain and also improve our muscles. In order to stimulate your muscles better, eccentric contractions or eccentric exercises work better.

Examples of eccentric exercise

For example, even just sitting down, like this, maybe you can move your arms, then you can use some weight to do the eccentric contractions. Or maybe whenever you stand up you can sit down slowly to do the eccentric contraction. For example, if you go to the toilet you have to sit down, you can sit down slowly to do the eccentric contraction.

Also you can do some kind of push up exercise, focusing on the eccentric phase. So maybe during watching TV, maybe during cooking as well, maybe you can stand on one leg and do some eccentric exercises.

So every opportunity you can find you can incorporate eccentric exercises in your daily activities.

How much eccentric exercise should I do?

If you could do a small amount of eccentric exercise every day, for example whenever you stand up you can sit down very slowly, which is a very good eccentric exercise. Also if you find stairs, you just need to go down the stairs and also if you have some dumb bells or bar bells you can just lower them slowly. So you can just accumulate those exercises in a day.

I think it is better to do a very small amount of eccentric exercise many times a day, instead of doing a very long eccentric contraction, or eccentric exercise only once a day. Because there are several studies showing that even when you are doing exercises, sitting time is harming your health. If you are sitting for a long time without any exercise, that can impair your body function.

So if you can do eccentric contractions every 30 minutes or every hour, that is great. But it is not necessary to do a very large amount. If you can do a very short eccentric contraction, every thirty minutes or every hour, this is very effective. Then eventually you are doing lots of eccentric contractions using the whole body. So maybe accumulation of exercises can be only ten minutes, but it is still very effective. So you just need to do eccentric contraction on a regular basis.