When most people in the gym lift weights, they tend to pick a number of reps and just aim to ‘get the weight up. However, that’s not the only phase of a repetition. Each lift can have three distinctive phases: the concentric, the eccentric, and the isometric phases. Knowing the difference between them can help us rehab, strengthen, and break through plateaus.

The Concentric Phase

This is the phase of the lift that most people focus on. This is the part of the lift that we ‘lift up the weight’, fighting against either gravity, or the resistance of a cable/band. What occurs in this phase of the lift is that the muscle shortens, where it is usually at its strongest. For a bicep curl for example, this is where the dumbbell is up and the elbow is bent. That’s the concentric portion of the lift.

The Eccentric Phase

Then there's the other part of the exercise, the eccentric phase. That's when you’re lowering the weight back to the floor in a set of deadlifts, the descent of a squat, or lowering the weight towards your chest on the bench. In this phase, the muscle is lengthening. To get the most out of this phase, the weight is slowly lowered with control, rather than dropping it down. So instead of just letting the weight drop to your chest in a bench press, the your muscles are resisting gravity, providing some force against the weight so its speed is controlled.

The Isometric Phase

But there's actually one more phase that you shouldn't ignore. The isometric portion of the exercise happens between these other two phases. If you’ve heard of isometric exercises before, it’s probably for stuff like planks or squat holds—moves where you hold a contraction in one spot and engage your muscles against an outside force, like gravity or a fixed bar. This can be an ideal opportunity to ratchet up time under tension, which in turn can spur strength and size gains. But moving lifts (called isotonic exercises) also have an isometric portion, when the weight isn’t moving between reps, even if it’s just for a split second.

If you have any questions on whether physio is the best option for you, or you have any questions about MVMNT in general, feel free to contact via email.

- Jay Towolawi, Specialist Sports Physiotherapist and MVMNT Founder.