You may see in your instructions that an exercise is “OK to fail.” In this post, I want to discuss what that means and how we utilize it in our training.

Failing, for our purposes, refers to a concept I call "honest failing" or an "honest fail."

An honest fail occurs when there is a degradation in performance while maintaining good technique with a specific exercise.

A degradation in performance is usually marked by a reduction in speed or cadence when performing an exercise.

Exercises that lend themselves well to “honest fails” are machine-based and isolated exercises, although this concept is not limited to these.

These types of exercises mitigate the possibility of technique degrading due to fatigue, thereby reducing the risk of injury from loading muscles that may not be prepared to handle certain intensities.

Machine-based and isolated exercises are more prone to elicit local fatigue, which is fatigue that accumulates in the muscle itself. This allows for more motor unit recruitment within the targeted muscle.

This differs from central fatigue, which is fatigue of the entire system and decreases overall motor unit recruitment.

When an exercise is listed as “OK to fail,” it means you are free to take yourself to the limit of absolute failure with this specific exercise, as long as you feel motivated and your readiness score is 3 or higher.

That being said, there are a few caveats to consider:

• Stop if the target muscle is no longer the limiting factor, meaning you feel another muscle taking over to complete the exercise.
• Stop if you can no longer maintain the same range of motion without compensating.
• Stop if you experience the onset of or an increase in pain.

If none of these occur, feel free to challenge yourself. If you have any questions, let me know. Until then, happy training!