Resistance Training: To Failure or Not to Failure?

Bodyweight training vs traditional strength training:

If our training goal is to perform a skill or movement that we are aren’t able to due to an inability to overcome our own bodyweight against gravity (e.g. a rings pullup) we need to start by employing tactics to reduce our percentage bodyweight. This will let us be able to perform at least one repetition in the first place.

Common ways to bridge this gap in a pullup example would be to employ resistance band or partner assistance while hopefully not influencing how the movement is coordinated drastically for best cross-over to the unassisted task.

How much help we get will determine what repetition range we can achieve before form failure. Resistance training performed until volitional failure is best performed at high loads if the aim of training is to improve how much of something we can lift. Performing an exercise in the 1-6RM (repetition maximum; the highest amount of resistance we can overcome for a given repetition number) range or 80-100%RM is desirable if we want to maximise the amount of force we can exert. If we can’t lift our bodyweight without help then that’s the aim and performing lower intensity ranges, such as 10-12RM has been shown to be less effective (particularly in trained individuals).

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What is “form failure”?

When we can’t perform a repetition of an exercise with the desired form due to fatigue, compensations begin to kick in if we push through this.

Common compensations

·      Partial repetition ranges- performing a shorter range of the movement

·      Using momentum, often from other body segments to lighten the load and break the inertia of the movement

·      Increasing reliability on the assistance aid (e.g. partner applying more force to further lighten your % bodyweight) effectively turning the exercise into a drop set

·      Shifts in body position to get less fatigued muscle in a better position to do the work

It’s very common to push to failure and beyond in the belief that this effort will be met with reward. In this case improved motor unit activation (improving how much muscle fibre gets recruited to help the movement) and mechanical stress for muscle adaptation; the net result being we can do more with less help or achieve more repetitions with the same amount of help. But is that how it works? Is it worth trying to squeeze out that extra repetition when we know we’re already toasted?

If we’re training for strength is it better to train to failure or leave something in the fuel tank?

Cue the concept of repetitions in reserve (RIR):

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RIR refers to how many repetitions you can complete before failure on a set of exercises. 0 RIR would be an exercise performed to failure and 1 RIR would mean you’ve got one repetition left in the tank that you’ve decided not to perform. RPE (rating of perceived exertion) or high hard you perceive yourself to have worked can be linked with RIR as with the table above. E.g. an RPE of 10 (maximum effort) would be a RIR of 0 (can’t do another repetition).

Too much training on the high intensity spectrum of maximal strength training at 0 RIR/ to failure has been shown to impair adaptation compared with mixing this with more sub-maximal training e.g. 5 repetitions@1 RIR through to 3 repetitions@3 RIR. In short sustaining high intensity practice isn’t sustainable or optimal and constantly training to failure session in session out may be doing more harm than good. In other words it’s ok to take things easier at times, and actually necessary.

What RIR you use will alter depending on how you’re feeling heading into your session (overloaded or energetic) or how heavy the warm-upsets felt on the RPE scale. RIR can more flexibly reflect our current state in comparison to loads based off of repetition maximums which don’t take into account wider psychophysiological influences (poor sleep, nutrition, stress etc.) which have been shown to negatively affect strength training.

Special note:  It is absolutely worth mentioning that in the early period of training a new skill, or with complicated movements that motor learning factors will play a large role in the improvement in performance. Improvements in the coordination and timing of muscle patterns will make the movement effectively lighter. Some of this is intuitive as our body figures out the most efficient way of performing the task in trial and error fashion, or through good coaching of intrinsic(internal) and extrinsic (external) movement cues. Depending on the complexity of the skill the focus might be on learning (low fatigue, quality repetitions)or building capacity (strength, endurance, power training).

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Summary of Key Points:

·      Resistance training exercises- bodyweight or otherwise- do not need to be performed to failure for best strength adaptations all the time

·      Performing to failure (and beyond) increases recovery demands between sets and between sessions

·      Repetitions in reserve (RIR) is a good method of gaging the intensity of a set without the need to calculate weight/ resistance based on repetition maximum

·      Rather than chasing a desired repetition number and watching form fail the closer you get, it might be worth using RIR and form to decide when it’s time to stop

·      It’s still ok and right to train to failure at times- there are still benefits- but only training at high/ maximal intensities can impair training adaptations

References

Helms,E., Cronin, J.B., Storey, A.G., & Zourdos, M.C. (2016). Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training. Strength and Conditioning Journal, 38, 42 - 49.

Gonzalez-Badillo JJ, Izquierdo M, and Gorostiaga EM. Moderate volume of high relative training intensity produces greater strength gains compared with low and high volumes in competitive weightlifters. JStrength Cond Res 20: 73–81, 2006.

Peterson MD, Rhea MR, and Alvar BA. Maximizing strength development in athletes: A meta-analysis to determine the dose-response relationship. J Strength Cond Res 18: 377–382, 2004.

Bulbulian R, Heaney JH, Leake CN, Sucec AA, and Sjoholm NT. The effect of sleep deprivation and exercise load on isokinetic leg strength and endurance. Eur J Appl Physiol Occup Physiol 73: 273– 277, 1996.

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Learn More:

Rehab vs Training

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