Is Training to Muscle Failure Essential for Building Muscle?

Anyone who trains regularly for strength will eventually ask: Should I train to muscle failure? To answer that, it’s important to understand what muscle failure actually means. Here’s a breakdown:

Two Types of Muscle Failure

1. Technical Failure: This happens when you can no longer perform an exercise with proper form. For example, during squats, you may lose the ability to keep your upper body stable or reach full depth. In a barbell bench press, technical failure might show as a lack of control, uneven pressing, or even developing a hollow back. Essentially, you continue until maintaining the correct form becomes impossible.
2. Complete Failure: This usually occurs with isolated exercises, like biceps curls. A classic example: you keep curling until you literally can’t bend your arms anymore. On a muscular level, this is caused by the buildup of hydrogen ions and lactic acid, making it impossible for the muscle to function until it gets proper rest.

Comparison Between Heavy Weights and Light Weights

When training until muscle failure, another key question often arises: Do I need to lift heavy weights, or can light weights achieve the same results? A study published in the Journal of Strength and Conditioning Research explored this. Male participants trained on a leg extension machine twice a week for 12 weeks. One group lifted at 80% of their one-repetition maximum (1RM), while the other lifted at 30% of their 1RM. Both groups trained to complete muscle failure.

The results showed that both groups were able to increase their strength and muscle mass, with no significant differences between them. This suggests that you can achieve muscle-building goals with both heavy and light weights. Another study, also conducted with male participants, confirmed these findings.

The Body Reacts Differently in Women

At first glance, it may seem like a strange question, but women actually respond differently to strength training to muscle failure compared to men. A study published in the European Journal of Translational Myology examined this. Female participants were split into two groups:

• One group performed three sets at 70% of their one-repetition maximum (1RM) twice a week for 10 weeks, training until muscle failure.
• The other group performed three sets of seven repetitions at 70% of their 1RM without reaching muscle failure.

The results showed that the group training to failure did not experience any additional strength or endurance gains compared to the non-failure group. Training to failure had a slightly negative effect on strength development in women. However, in terms of muscle growth, both groups saw similar results.

How Important is Training to Muscle Failure for Hypertrophy?

Training to failure and training close to failure (1-2 reps short of failure) appear to produce similar hypertrophy results:

• A meta-analysis found no significant difference in muscle hypertrophy between training to failure and conventional training that stops short of failure.
• A study on resistance-trained males showed similar quadriceps hypertrophy when training to failure versus stopping 1-2 reps short of failure over 8 weeks.

However, there are some nuances: For untrained individuals, training to failure seems unnecessary for maximizing muscle growth. For trained individuals, some evidence suggests training to failure may have a slight edge for hypertrophy, but more research is needed.

Muscle Activation and Recruitment

Training close to failure appears sufficient to maximize muscle activation:

• Full muscle activation can be achieved 3-5 repetitions before failure, even in untrained individuals.
• Training with 1-2 reps in reserve likely provides enough stimulus for muscle growth without the added fatigue of reaching complete failure.

Practical implications