3 Various Stages of Muscle Contractions
In most movements that we perform, the muscle goes through three general stages of contraction.
Eccentric (Lowering)
This is when the muscle lengthens and we lower the weight to the ground. In a back squat, this is our descent. In a pull-up, this is going from our chin at the bar to our elbows fully extended at bottom. You get the idea. We’ve written a lot about the benefits of eccentric contractions and as you think about your movement in the context of this article, we want you to think about it as the most “important.” This is where the majority of our progress occurs in the form of muscle growth and strength adaptations, and it is also where the majority of our bad habits can get formed. Most modern strength and muscle research points to the eccentric phase as the most impactful when it comes to developing muscle.
How to take advantage: Control your eccentrics as much as possible, never let the weight crash down using momentum.
Concentric (Lifting)
This is the opposite, when the muscle shortens and when we “lift” the weight. Driving back up in the back squat and pulling our chin up towards that bar in a pull-up. While eccentrics drive the bus when it comes to our results, we can’t have complete movement without a proper concentric phase. If all that we ever did was lengthen the muscle and not shorten it, we wouldn’t receive the complete benefits of growing muscle. We’re actively contracting against the direct pull of gravity in the concentric phase, which is why this phase is what tends to create the “pump.”
How to take advantage: Focus on a momentary peak contraction at the end range of motion when possible.
Isometric (Holding)
This is the part of the movement where the joints don’t move and the muscle doesn’t actively lengthen or shorten at all, but instead hold its position at whatever joint angle you’ve created. It could be holding bells for a farmer walk, a half rack position, even something as simple as holding dumbbells while you lunge. We think of that as a lower body movement, but what about those arms actually holding the weight?
Isometrics are very effective. OG strength scientist Mell Siff says this is where our muscles are most active and where lots of progress can occur, and it’s also a great way to build muscle endurance. The reason why we love carries in all shapes and sizes is we’re training our muscles to grow and get stronger, but we’re also training the endurance of some very important spinal stabilizers, making your less susceptible to back injuries.
How to take advantage: Be as rigid and activated as you can when in state of holding a position.
Three phases of movement, each one with its unique benefits. Enjoy them all.