There are 3 ways your brain can instruct your muscles to work;
Concentric – contracting and getting shorter
Eccentric – contracting and getting longer
Isometric – contracting and staying the same length
Learning about these and harnessing them in your workouts can help you to reap the full benefits of the effort you put into exercise.
Think, bicep curl. You shorten the bicep muscle by closing up the elbow. The muscle works hard to shorten it’s length. Your muscle overcomes the resistance of gravity, increased by holding a weight, and works against that load to shorten. These types of exercises build strength in muscles, and are the basis of a lot of static weight machines seen in gyms.
To get the muscle to contract and lengthen at the same time, a slow, smooth movement to lengthen a limb is normally required. These muscle contractions are normally seen in pilates based workouts– which focus of control and lengthening.
You can build an eccentric phase into weight lifting, by controlling the release of a weight in a slow and smooth manner – think about times you’ve been told to lift “up for 3, down for 6”
Your muscles are working super hard, but you’re not really getting anywhere! Typically this is the least favourite kind of muscle contraction. If done correctly, you’ll be activating a muscle very, very well – think of holding a squat position for a long time! This will build an endurance, and a serious burn, into your workout!
The main thing to take away is that building lean, strong muscles requires all 3 kinds of muscle activation!