Training to Failure Every Set: Pathway to New Muscle or Pathway to Overtraining?
By: Robbie Durand
Seven Time Mr. Olympia Arnold Schwarzenegger said in the movie Pumping Iron, “Muscle growth does not take place until the repetitions are taken place the point of failure.” There have been many great Olympians such as Dorian Yates and Ronnie Coleman that took every set to complete muscular failure. Many people have the notion that you are not hardcore if you are not taking every set to complete muscular failure, and most trainers and athletes have advocated that repetition failure to failure is an essential characteristic of resistance training regimen. To date there is only a single exercise study reporting training to failure may lead to greater increases in strength and hypertrophy. Two studies had caused controversy in the resistance training research realm when experimental groups were matched for total work, observed isometric force production, single repetition maximum strength, local muscle endurance, and explosive power gains were similar regardless of whether the sets were taken to complete muscular failure or not. Some researchers have advocated that taking every set to total failure leads to long-term overtraining, which may be counterproductive to muscle growth.
There has not been a training to failure study for some time, so researchers decided to investigate the subject once again. To compare the increases in muscular strength, size, and neural activation between three resistance training programs in which the participants always trained to muscular failure or predominantly not to muscular failure. 28 previously untrained males, who first undertook a 4-week period of standardized resistance training to muscular failure before being designated as either high or low responders and then randomly allocated into one of 3 different groups. All groups performed a 12-week resistance training program comprising four sets with 85% of 1RM for the elbow flexors, training three times per week. The three treatment groups were differentiated in two ways:
(a) the speed in which the elbow flexion-extension movement was performed, and,
(b) the number of completed repetitions within each set. The failure group performed all sets to muscular failure (typically six repetitions in each set) and trained using a 2-second concentric and a 2- second eccentric muscle action. The fast-concentric, not to-failure group trained without going to muscular failure (4 repetitions per set) and trained using a maximal concentric and a 2-second eccentric muscle action. Finally, the fast-not-to-failure group trained without going to muscular failure (4 repetitions per set) and trained using a maximal concentric and a maximal eccentric muscle action.
Both not-to-failure groups performed 1 set per week to failure to ascertain the loading for the subsequent week. At the end of the study, the researchers reported that although all three groups increased muscular strength in the arms, there were no significant differences between groups. Similarly, they reported that although all three groups increased muscle size in the arms, there were no significant differences between groups. The researchers concluded that training to muscular failure was not necessary to achieve gains in strength and size.
Training to Failure Increases Cortisol Production Post-Exercise
The newest study has reported that training to failure can lead to elevated cortisol levels for 48 hours after exercise. Researchers examined post-exercise anabolic effects after two resistance training (bench press and squats) workouts:
-performed either close to muscular failure, 12 repetitions to failure with 70% of 1RM
-Further away from muscular failure, three sets of 6 repetitions (Not to Failure).
Recovery was assessed by reference to counter- movement jump height (measured with an infrared timing system), bar speed in the exercises (measured with a linear velocity transducer), hormonal and metabolic responses at 6, 24 and 48 hours post-workout.
At the end of the study, the researchers found that training to failure had adverse outcomes on muscle recuperation. The researchers reported that training to failure resulted in greater increases in cortisol (measured immediately post-exercise), and markers of muscle damage (creatine kinase were elevated 48 hours post-exercise). Training to failure led to a lower bar speed compared to not training to failure when measured up to 24 hours post-exercise for the bench press (65% reductions in bar speed after training to complete failure versus 26% reduction in bar speed after non-training to failure), and up to 6 hours for the squat (44% reduction after training to failure versus 20% reduction after not training to failure). Training to failure also led to a lower jump height compared to not training to failure when measured up to 48 hours post-exercise.
This study shows that the mechanical, neuroendocrine and autonomic cardiovascular response is markedly different when manipulating the number of repetitions per set. Halving the number of repetitions in relation to the maximum number that can be completed serves to minimize fatigue and speed up recovery following resistance training.
Key Points: Training to complete muscular failure results in increased cortisol productions and delayed muscle recuperation. If you do train to failure, than you may need to train less often or try keeping your reps lower as the study did. Based on the research, training to failure each workout may lead you on the pathway to overtraining.
Acute and delayed response to resistance exercise leading or not leading to muscle failure, by Pareja‐Blanco, Rodríguez‐Rosell, Sánchez‐Medina, Ribas‐Serna, López‐López, Mora‐Custodio & González‐Badillo, in Clinical Physiology and Functional Imaging)
Folland JP, Irish CS, Roberts JC, Tarr JE, Jones DA. Fatigue is not a necessary stimulus for strength gains during resistance training. Br J Sports Med 2002: 36: 370–374.