By Training to Failure are you Failing to Train Effectively?

There are many in the fitness and bodybuilding world who believe that training instinctively and training to failure on a regular basis, even so much as to train to failure on multiple exercises within a single training session, is the most rapid and effective method of gaining muscle. However, within powerlifting circles it is often recommended that failure should be avoided as much as possible, and that the number of sets and repetitions within a training session should be accurately calculated and periodised in order to avoid excessive fatigue. In the following article we will review the available scientific literature to obtain the evidence both for and against training to failure.

It is commonly believed that training to muscular failure is necessary to maximise the hypertrophic response¹. Failure has been defined as “the point during a set when muscles can no longer produce the necessary force to concentrically lift a given load”². A number of studies have demonstrated the benefit of training to failure compared to stopping short of failure in each set. Rooney and colleagues³ identified that strength gains were significantly greater when a 6 Repetition Max (RM) load was lifted for 6 repetitions without rest compared to when the same load was lifted and equal number of times, but with 30 seconds rest between each lift in order to avoid fatigue. With regards muscular hypertrophy, Folland et al⁴ discovered that stopping short of failure yielded modest hypertrophy compared to training to failure, even when training volume was equated. Finally, it has been identified that training to failure may increase local muscular endurance to a greater extent than avoiding failure during training⁵.

The primary mechanism for which training to failure has been hypothesised to stimulate increased strength and hypertrophy involves the activation of a greater number of motor units^1,6,7. Muscular fatigue activates a progressively greater number of motor units in order to continue the performance of exercise, and therefore training to failure and maximum fatigue may provide additional stimulus for hypertrophy. Additionally, it has been proposed that failure may therefore increase the stimulation of high threshold motor units, which are activated when training at maximal effort². However, sufficient data to support these theories of increased motor unit activation as a result of fatigue is lacking. Alternatively, training to failure has been suggested to enhance hypertrophic response to training by increasing exercise-induced metabolic stress The continuation of training despite fatigue involves the continuation of anaerobic glycolysis which results in the accumulation of metabolites and in turn may increase the anabolic hormone response^1,8. However, as with the previous hypotheses, there is little data available to support this. Despite the lack of sufficient data supporting the benefits, and underlying mechanisms, of training to failure, it may help advanced athletes to break through plateaus and should only be incorporated in short microcycles to avoid overtraining¹.

Although there is limited evidence supporting training to failure, there is a greater volume of evidence suggesting that avoiding failure may in fact be more effective in inducing strength and muscle gain. Izquierdo and colleagues⁵ performed a study in which 42 male participants trained to failure, non-failure or did not train at all (control). As a result of this investigation, the authors noted that failure and non-failure training resulted in similar increases in 1RM bench press; squat, bicep and leg extension power output; and the maximal number of squat repetitions performed. After over 11 weeks of training, although training to failure increased the maximal number of repetitions performed on the bench press, non-failure training resulted in larger gains in power output of the lower extremities. Additionally, this study also indicated that non-failure training reduced resting cortisol and increased serum testosterone. Sanborn et al⁹ also found that multiple sets of squats not to failure induced greater increases in squat 1RM and vertical jump than a single set of squats of failure. A more recent study in rowers¹⁰, demonstrated that greater increases in maximal strength and power were observed when four sets of rowing was performed not to failure compared to two sets to failure. Further, both two sets and four sets not to failure resulted in significantly greater increases in rowing power compared to multiple sets to failure. Finally, an experiment in women alone¹¹, in which participants performed multiple sets of leg extensions and machine seated bench press to failure or not to failure, identified that training not to failure induced greater increases in leg extension and seated bench press 1RM strength compared to failure training, which in fact did not produce any significant increase in seated bench press 1RM.

A number of negative consequences have been associated with regularly training to failure, including an increased risk of overuse injuries, overtraining and psychological burnout^1,6,12. It has been specified that training to failure for over 7 weeks will significantly increase an individual’s risk of overuse injury and overtraining⁶. Additionally, multiple sets to failure with short rest periods between sets has been found to induce significant Delayed Onset Muscle Soreness (DOMS) which may be detrimental to performance in the short term¹³.

Stone and colleagues⁷ aptly describe the pitfalls of the argument in favour of training to failure. They highlight that if fatigue and exercise to failure were in fact a critical strength training stimulus, simply training to failure with a light weight would produce significant strength gains. However, this does not appear to be the case. Instead, increased resistance and the recruitment of additional motor units have been strongly correlated with both hypertrophy and strength gains. Therefore, training intensity (average weight lifted) and relative intensity (%1RM) may be more important training factors than training to failure, particularly in advanced lifers.

In conclusion, the body of research would suggest that utilising multiple sets whilst avoiding failure is superior to training to failure for increasing maximal strength and power, and that failure may not be essential for in strength and muscle gain. Although the long term benefits of training to failure are still equivocal, it should be noted that training to failure may be effective in increasing local muscular endurance⁵ and may assist advanced athletes in breaking through plateaus. However, it must be recognised that the duration, frequency and volume of sessions in which failure is utilised should be limited and periodised, and that failure is not an effective training stimulus without sufficient training intensity (%1RM).

References

1. WILLARDSON, J.M., 2007. The application of training to failure in periodized multiple-set resistance exercise programs. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, May, vol. 21, no. 2, pp. 628-631 ISSN 1064-8011; 1064-8011. DOI R-20426 [pii].

2. SCHOENFELD, B.J., 2010. The mechanisms of muscle hypertrophy and their application to resistance training. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, Oct, vol. 24, no. 10, pp. 2857-2872 ISSN 1533-4287; 1064-8011. DOI 10.1519/JSC.0b013e3181e840f3 [doi].

3. ROONEY, K.J., HERBERT, R.D. and BALNAVE, R.J., 1994. Fatigue contributes to the strength training stimulus. Medicine and Science in Sports and Exercise, Sep, vol. 26, no. 9, pp. 1160-1164 ISSN 0195-9131; 0195-9131.

4. FOLLAND, J.P., IRISH, C.S., ROBERTS, J.C., TARR, J.E. and JONES, D.A., 2002. Fatigue is not a necessary stimulus for strength gains during resistance training. British Journal of Sports Medicine, Oct, vol. 36, no. 5, pp. 370-3; discussion 374 ISSN 0306-3674; 0306-3674.

5. IZQUIERDO, M., IBANEZ, J., GONZALEZ-BADILLO, J.J., HAKKINEN, K., RATAMESS, N.A., KRAEMER, W.J., FRENCH, D.N., ESLAVA, J., ALTADILL, A., ASIAIN, X. and GOROSTIAGA, E.M., 2006. Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength, and muscle power gains. Journal of Applied Physiology (Bethesda, Md.: 1985), 20060112, May, vol. 100, no. 5, pp. 1647-1656 ISSN 8750-7587; 0161-7567. DOI 01400.2005 [pii].

6. TAN, B., 1999. Manipulating resistance training program variables to optimize maximum strength in men: a review. The Journal of Strength & Conditioning Research, vol. 13, no. 3, pp. 289-304.

7. STONE, M.H., CHANDLER, T.J., CONLEY, M.S., KRAMER, J.B. and STONE, M.E., 1996. Training to muscular failure: is it necessary?. Strength & Conditioning Journal, vol. 18, no. 3, pp. 44-48.

8. LINNAMO, V., PAKARINEN, A., KOMI, P.V., KRAEMER, W.J. and HAKKINEN, K., 2005. Acute hormonal responses to submaximal and maximal heavy resistance and explosive exercises in men and women. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, Aug, vol. 19, no. 3, pp. 566-571 ISSN 1064-8011; 1064-8011. DOI R-15404 [pii].

9. SANBORN, K., BOROS, R., HRUBY, J., SCHILLING, B., O'BRYANT, H.S., JOHNSON, R.L., HOKE, T., STONE, M.E. and STONE, M.H., 2000. Short-term performance effects of weight training with multiple sets not to failure vs. a single set to failure in women. The Journal of Strength & Conditioning Research, vol. 14, no. 3, pp. 328-331.

10. IZQUIERDO-GABARREN, M., de Txabarri Expósito, Rafael González, de Villarreal, Eduardo Sáez Sáez and IZQUIERDO, M., 2010. Physiological factors to predict on traditional rowing performance. European Journal of Applied Physiology, vol. 108, no. 1, pp. 83-92.

11. SCHLUMBERGER, A., STEC, J. and SCHMIDTBLEICHER, D., 2001. Single-vs. multiple-set strength training in women. The Journal of Strength & Conditioning Research, vol. 15, no. 3, pp. 284-289.

12. FRY, A.C. and KRAEMER, W.J., 1997. Resistance exercise overtraining and overreaching. Sports Medicine, vol. 23, no. 2, pp. 106-129.

13. GOTO, K., NAGASAWA, M., YANAGISAWA, O., KIZUKA, T., ISHII, N. and TAKAMATSU, K., 2004. Muscular adaptations to combinations of high- and low-intensity resistance exercises. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, Nov, vol. 18, no. 4, pp. 730-737 ISSN 1064-8011; 1064-8011. DOI R-13603 [pii].