Triphasic training, made prominent by Cal Dietz, gets a lot of attention in the sports performance world – and for good reason! Below we dive into the application of three phases – eccentric, isometric, and concentric – and how they translate to performance.
Gravity is always acting against us. So the better we become at withstanding external forces, the better and faster we can act against them. This is where an individual’s eccentric strength comes into play. Sometimes we train this phase with heavy resistances and yield against them slowly. Other times, as demonstrated in the box drop video below, the goal is to stop the external forces as abruptly as possible.
Once we’ve stopped the forces there’s a momentary pause in muscle length, joint angles, and momentum. This is the isometric phase of an action which we can train by loading fixed positions. Often time we aim to strengthen the “hardest” part of a movement, like the bottom of a split squat (below) which has a direct with link to the critical moment when changing direction.
This next clip is a great example of how it all comes together in a sport-specific athletic movement. Notice how his inside leg begins to decelerate his momentum, and steadily bends at the ankle, knee and hip while doing so. This represents the Eccentric portion of the cut where he is withstanding the forces produced from momentum and gravity. Then there is the split second where he comes to a complete stop. This transition from decelerating to accelerating represents the Isometric portion of the cut. His joint angles are fixed (just for a moment!), as he begins to reapply force in the opposite direction.
Finally, we see the moment when he turns and accelerates towards the finish. This is the Concentric phase and is present in nearly every movement we execute. This is the portion of movement we most often associate with weight training. How we go about this phase is extremely important and why we preach intent in this portion of the exercise – explode out of the bottom of a lift, jump as high as you can, throw as hard as you can! Because when it gets back to the sporting movement, we want to have trained in a way that translates.
Intentionally training the three different phases helps athletes in a myriad of ways that more traditional training may lack. We also find emphasizing the different phases to be a major benefit to novice athletes as slowing them down gives them a better opportunity to learn movements correctly and for us to coach them!