When a muscle contraction take place the tiny myofilaments which are actin and myosin make over each other to basically create tension in the muscle and there is different ways that this contraction happen switch on the muscle and often relaxed it on and contracted and that’s things you need to know about from the simplistic point of view.
When we look at the different types of muscle contraction, the primary thing that is different is about the lengthening, shortening and the overall length of the muscle during the contraction.
Basically, there are two types of muscle contraction. The Isotonic muscle contraction and Isometric muscle contraction.
Isotonic Contraction:-
Iso means same and tonic means tone. In isotonic muscle contraction the tension of muscle remain the same and movement of joint take place. The Isometric contraction give us a real little hind that it has a word tonic or tone. When we talk about contraction, it’s all about muscle moving.
There is actively two kinds of contraction underneath that is Eccentric contraction and Concentric contraction.
Concentric Contraction:-
Concentric contraction is the shortening of the muscle fibres. It is a type of contraction which we use all the time when we’re at the gym. So let’s take Biceps brachii as our example. A lot of time you do the biceps curl and it’s origin is on the supraglenoid tubercle and the coracoid process of scapula. It’s insertion is the radial tuberosity on the radius. When we feel that muscle belly, we get those muscle fibres to shorten and that’s it’s job. It’s action is flexion of elbow. When we get it to shorten and you feel a bunch up underneath there, that’s concentric contraction.
Eccentric Contraction:-
Eccentric contraction is the lengthening of the muscle fibres. Now, let’s go in the opposite direction of elbow flexion to extension. It’s working while those muscle fibres are getting longer and lengthening.
So when we look at isotonic contraction, we have Concentric and Eccentric Contraction.
Isometric Contraction:-
Iso means same and metric means length. In isometric muscle contraction the length of the muscle remain the same and there is no any movement at joint level . When we talk about isometric contraction, then take a empty glass of water in your hand. Make sure the joint angle of elbow remain the same, biceps still engaged and if we start to fill up that glass with water then at that time my muscles still working. The muscle is contracting but joint angle is not change. We see this all the time in yoga, when we hold a pose and then the muscle fatigue because of its working for a long period of time. Example of Isometric contraction is the position of plank and pushing the wall. While pushing the wall, the muscles of body got contracted but the length of muscle remain the same because we are not moving the joint and the joint angle does not change.
So, Isometric contraction is more muscle work applied more load but no joint angle change. Under Isotonic contraction, Eccentric muscle contraction and Concentric muscle contraction under Isometric maintaing joint angle but increase the workload.