What is training to failure and should you train to failure?

This is a highly debated topic in bodybuilding, and I think it deserves some clarification.

Because a lot of people talk about training to failure, always trained to failure,

train to absolute failure.

I train until I can get every possible rep, but failure is actually defined a little bit differently than most people think.

So this is coming from a meta-analysis from 2022 called Intensity of Effort and Momentary Failure and Resistance Training.

Are we asking a binary question for a continuous variable

by James Fisher, James Steele, and Dave Smith? And the key quote I want to pull out of this is

for this piece, momentary failure is defined as the point trainees reach where, quote,

despite attempting to do so, they cannot complete the concentric

portion of their current repetition without deviation from the prescribed form of exercise.

Furthermore, we have termed this momentary failure rather than muscular failure herein because

there is no current consensus on where the lack of continued

ability to carry on with the task despite attempts to do so arises, e.g. centrally at the neural

level or peripherally at a motor neuron end plate or muscular level. So I'll explain that last

bit in a minute. But the important piece here is where you cannot

complete the concentric portion of the current repetition.

So what does that mean?

Let's say you're doing a leg press and you can do 10 full reps without assistance, without pausing, whatever.

Within the current form guidelines you have of depth, how you're controlling the eccentric,

how much you're moving and using other parts of your body, like your hips or your back.

And you can do 10 full,

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