In resistance training, reaching true momentary muscular failure significantly increases both perceived and physiological fatigue without providing additional muscle hypertrophy benefits compared to terminating sets a few repetitions before failure, resulting in a less favorable stimulus-to-fatigue ratio.

When muscles are pushed to complete failure, nerve signals to the muscle weaken and metabolic byproducts build up, making it harder to perform the next set. This fatigue reduces the total number of repetitions you can do across all sets, so the muscle doesn't get more total work than if you stopped a few reps short. Since muscle growth depends on total work done, not how close you get to failure, both approaches build the same amount of muscle — but failure leaves you more exhausted.