Concentric, Isometric and Eccentric’s are all phases of movement. You may have heard these terms before but not understood what they are. We’ll explain in simple terms exactly what they mean, and how you can utilise Concentric, Isometric and Eccentric movements to increase muscle activation and get stronger faster.
The Concentric phase of an exercise is the closing or shortening of the muscle. The muscle fibres contract, bringing the muscle connection points closer together. During a Bicep Curl, the Concentric phase is lifting the weight up, starting with a straight arm and finishing at the top.
The Isometric phase of an exercise is any point where the muscle is engaged, but no movement is occurring. The joint is static and there is no movement. During a Bicep Curl, this would be any part of the Curl where the hand is static.
The Eccentric phase is the opening or lengthening of the muscle. The muscle fibres are lengthening, increasing the distance between the connection points. During a Bicep Curl, the Eccentric phase is the lowering of the weight, from bent arm to straight.
Your body is strongest in the Eccentric phase, second is the Isometric, and weakest in the Concentric
It’s for this strength reason that when someone is using a weight too heavy, for example in the Squat, they can lower down but not press back up. The same on a Bench Press, it’s possible to lower the bar slowly, but then not be able to press it back up.
Utilising Concentric, Isometric and Eccentric movements to get faster gains
Muscle fibres are just like the fibres of a rope. When we gain muscle, we don’t actually increase the number of fibres, but we increase the size of the fibres. By training we tear the fibres, and the body utilises protein to repair the fibres stronger than they were before.
You cannot snap a rope by pushing it together.
Eccentric movements are essential for muscle growth as they tear the muscle fibres
All phases are key to building muscle. The Concentric phase fatigues the fibres, making it easier to tear them. The Eccentric phase does the stretching and tearing of the fibres.
Recommendation to maximise all phases of the movements.
Fatigue your muscles with plenty of Concentric contractions ‘squeezing’ the muscle as hard as possible. This is ideally done with resistance bands, using an isolation exercise like Chest Flies. Available now as a set in The Flex. You can even utilise this to pre-exhaust the muscles before compound movements.
Then hold a variety of Isometric positions to fully fatigue the fibres.
Lastly perform Eccentric repetitions and full a muscle stretch to ensure the fibres tear.