Delayed Eccentric Action

Delayed Eccentric Action (DEA) is one of Exxentric's methods for eccentric overload using flywheel training on the kBox.  


Delayed eccentric action is when you brake hard in the end of the eccentric (ECC) phase and it works with all kBox drills but it only offers overload in a limited part of the ECC range of motion and a low degree of total overload. Similar to Impulse Overload.  

How to do it

Generate rotational energy in the concentric (CON) phase using the primary muscle group you are working. In the ECC phase follow through without resisting until the end of the ECC phase and then resist hard to decelerate the flywheel and go into CON. Can be combined with Overloaded Concentric Action by using accessory muscles in CON and increase energy in ECC phase and by this you can increase peak ECC power or increase time under tension (TUT) in ECC.  

When you can use it

Can be used in all exercises.  

Good for

  • Learning eccentric overload (as tought in our courses).
  • Useful in drills when you can't get any other type of overload or don't have any spotter.
  • Useful when you want to load heavy in the ECC-CON shift or in the end of the ECC phase like the deep portion of a squat.


  • Low degree of total overload since the max total load, 1 RM CON only load the ECC portion to ≈70% of ECC 1 RM.
  • Not suitable for ECC overload in the beginning of the ECC phase.
    Proceed to learn more about our courses and equipment, or go back to the methods.

Learn More

Proceed to learn about the kBox flywheel training device. 

RDL delayedBy decelerating harder in the late ECC phase you excert a higher ECC power as shown in this kMeter reading.