Training to failure is not required for muscle growth. (1)
In fact, in many cases it can hinder it in the long term.
Before you starting quoting Arnold let me continue by saying that I’m not saying it doesn’t have a role to play.
It does.
Training till failure can cause increased stimulation of motor units and increase muscle fibre recruitment which indicates that it has the potential to increase muscle growth. (1)
However, it’s also demanding on your body. This is especially true during dieting periods, when energy levels are reduced and recovery capabilities are compromised. Strategically implementing training to failure during these times can help you avoid injury and negative performance effects.
Negative performance effects?
That’s right.
Despite the outlined benefits, training to failure creates high levels of fatigue both during the session and potentially long term if done frequently. This can affect your ability to train at optimal frequencies, volume and intensity.(2)
Think about it this way, training to failure results in greater fatigue and is therefor likely to reduce the total number of reps, weight used or exercises carried out during the session and therefor decrease the total training volume.
Research has indicated that total volume is likely more important in terms of making gains in strength and growth! (3)
There is also evidence to suggest that training to failure frequently can mess with your hormonal balance in a manner that is similar to what’s seen in overtraining syndrome in athletes. (4)
So no more reps till failure?
Never fear my fellow gym rats. Like I said at the beginning, training to failure does have a place in a training program and can be used to boost your gains!
It’s just about implementing it at the right time and with the right exercises rather than taking every set of every exercise to failure.
So when should I train to failure?
For starters, it may be of benefit to limit sets to failure on compound lifts which are highly taxing and require more concentration. Taking these sets to failure risks a greater chance of you ending up in snap city.
Isolation exercises on the other hand are considered less demanding on the body, recovery is quicker and therefor are more conducive to failure training.
What would this look like? Well maybe you do some lower rep heavy squats at 80-90% leaving a rep or two in the tank of each set then later in the workout feel free to go to town on some higher rep leg extensions till you fill ill in the stomach.
A 20+ rep set should do the trick. ;)
Higher rep sets to failure on isolation movements is also a great way to induce metabolic fatigue in the muscles and get the pumps we all love. Both of which play a role in maximizing hypertrophy. (5)
Wrapping up.
Training to failure should not be something that is performed for every set of every exercise each time you train. You will end up fatigued, stalling in lifts and gains, and increase the risk of overtraining or injury. Especially if you’re in a calorie deficit.
You’re better off focusing on total volume and progressive overload over time for your compound lifts and saving the failure work for high rep isolation work. Not only is this still fun (in a sickening kind way), but it also helps stimulate your muscles for hypertrophy.
If you do like to train compounds till failure, do it in a planned manner such as making your last set of a compound exercise an AMRAP (as many reps as possible) set every couple of weeks or so.
1) Willardson JM. The application of training to failure in periodized multiple-set resistance exercise programs. J. Strength Cond. Res. May 2007;21(2):628-631
2) Wernbom M, Augustsson J, Thomee R. The influence of frequency, intensity, volume and mode of strength training on whole muscle cross-sectional area in humans. Sports Med. 2007;37(3):225-264.
3) Krieger, JW. Single vs. multiple sets of resistance exercise for muscle hypertrophy: a meta-analysis. J. Strength Cond Res. 24: 1150-1159, 2010.
4) Izquierdo M, Ibanez J, Gonzalez-Badillo JJ, et al. Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength, and muscle power gains. J Appl Physiol (1985). May 2006;100(5):1647-1656.
5) Schoenfeld B. Repetitions and muscle hypertrophy. Strength Cond J. 2000;22(6):67