Strength vs. Hypertrophy Training: Selecting The Right Tool For The Job.

It has long been preached by gym goers and personal trainers alike that low repetition training (<6 repetitions) is optimal for strength gains rather than gains in muscle, and that high rep training (>8 repetitions) will lead to gains in muscle or hypertrophy, and will not significantly increase strength.

This dichotomy in opinion is a common theme in the fitness industry, with ‘black and white’ thinking increasingly prevalent. However, for many of the frequently debated topics there is often no right or wrong answer, and often, particularly in biology and physiology, the two situations may overlap depending upon circumstance. It can often be more logical to think of both situations as tools, either of which may be more preferable in certain circumstances. This article will explore whether a continuum between bodybuilding-style and powerlifting-style training exists or whether ‘black and white’ thinking does in fact prevail.

Anyone who has ever encountered an elite powerlifter in the flesh will appreciate that their training methods do in fact bring about significant muscle gains, and that many of them are a contest prep diet away from having a respectable bodybuilding stage physique. Just look up Jon Anderson, the author of Deep water training, for one example of many powerlifters who have taken the transition all the way and have stepped on a bodybuilding stage.

The size of the bodybuilding mass monsters of recent decades, many of whom utilise a high repetition training style, including the current Mr O, speaks for itself. However, it is also well known that many of the greatest bodybuilders in history have dabbled in powerlifting in their off season, including the Austrian Oak! The great Ronnie Coleman even incorporated maximal lifts deep into his preparations for the Mr Olympia- we’ve all seen the 800lb squat footage (Lightweight baby!). A number of bodybuilders have gone as far as to make the powerlifting pro ranks without straying far away from a respectable off season physique, for example Stan ‘The Rhino’ Efferding.

However, although there is plenty of anecdotal evidence supporting both high and low repetition training methods, there is currently little consensus in academic circles as to which method induces the greatest hypertrophy, with recent studies increasing the debate.

Much of the results from the early body of research conform to the widespread opinion that training with higher loads and lower repetitions equates to greater increases in power, lower loads and higher repetitions result in greater increases in hypertrophy, and lighter loads and ultra-high repetitions improves muscular endurance^{1, 2, 3}. The literature also confirms that no one training method is optimal in all situations and that each has its benefits and limitations.

 A number of studies have supported the hypertrophic benefits of high repetition training, and it has been proposed that the link between bodybuilding-style training and increases in muscle mass may be explained by the greater amount of total work performed, in comparison to traditional power training with lower amounts of total work performed⁴. High repetition, lower load training also been linked to an increase in maximum repetition velocity and, although the relative load (% 1RM) may vary between exercises, the optimal load for increased repetition velocity has been consistently found to be under 70% 1RM¹. These high volume regimes have also been found to elevate acute Testosterone and Growth Hormone levels to a greater extent than lower volume routines, and are therefore linked to greater anabolism⁵. More recent data presented by Burd and colleagues⁶, has also indicated that training with low loads may stimulate increased muscle protein synthesis (MPS) and, although it can be presumed that this would lead to greater hypertrophy, this was not measured in this particular study.

Research has also supported the generally accepted hypothesis that high load, low repetition training is most effective for increasing maximal strength^{1, 7, 8, 3}. De Vos and colleagues⁹ discovered a dose-response relationship between the training load and the improvements in muscle strength and endurance in older participants. Heavy strength training (80-85% 1RM) has also been found to be required to produce further neural adaptations in advanced lifters¹⁰. These improvements in nerve firing are commonly associated with strength gains in novice lifters who are yet to perfect the movement patterns for a particular lift.

However, it has been proposed that training with heavy loads may be essential to recruit high-threshold motor units that may not be activated during training with light or moderate loads¹. This may suggest that heavy load training is necessary in order to stimulate the hypertrophy of the muscle fibres which are activated by these high-threshold motor units.

Although, as described above, the majority of studies over the years have supported the commonly held opinions regarding strength and hypertrophy training, more recent investigations have challenged these hypotheses. In 2012, Mitchell and colleagues¹¹ discovered that, in novice lifters, training to failure induced similar hypertrophy regardless of whether the load was heavy or light. More significantly however, Schoenfeld et al⁷ identified similar hypertrophy in experienced lifters who undertook either bodybuilding-style or powerlifting-style training, and that powerlifting-style training was superior for gains in strength. The findings in this study call into question the commonly held beliefs regarding strength and hypertrophy training and are particularly relevant given the previous lifting experience of the subjects.

Tan³ identified a significant flaw in the majority of studies that have been performed regarding optimal loading within training regimes, namely that participants in high load training groups are exposed to such low volumes of work that little appreciable stimulus is put upon the muscle, and this may mask any efficacy of the training load. However, this is not the case in the most recent Schoenfeld et al⁷ experiment in which the number of sets was adjusted, depending upon the number of repetitions, in order to equalise the volume performed by each training group.

Although significant evidence now exists suggesting that low repetition training may induce similar gains in muscle mass, but greater increases in strength, compared to high repetition training, there may be some situations in which bodybuilder-style training may still represent a useful tool. For example, for those preparing for a bodybuilding show, high repetition training could be utilised to stimulate muscle protein synthesis, muscle gain, or at least muscle maintenance, with a reduced risk of injury from training with heavy loads. High repetition training could also be beneficial in contest preparation as a method of increasing calorie expenditure in comparison to low repetition, low volume, high load training.

High repetition, bodybuilder-style training may also be a useful mechanism for adding additional volume, during accessory exercises, when training weaker or lagging muscle groups that may not be significantly stimulated during compound movements. Improvements in neural function^{12, 13}, commonly known as the ‘Mind-muscle connection’, and resultant increases in muscle fibre recruitment and rate of force development, may also be an advantageous outcome of high repetition training, particularly during isolation exercises and in novice lifters. Incorporated correctly, high repetition training can also produce improvements in work capacity⁸, increasing the number of repetitions you are capable of performing at a given load, and therefore resulting in strength and muscle gains. Finally, to paraphrase Arnold in Pumping Iron, who doesn’t love the pump?

An alternative avenue of investigation in the quest for the ‘optimal’ training method has previously been proposed, namely a prescription of repetition ranges for each muscle or muscle group depending upon its muscle fibre composition (Type I, Type IIa, Type IIx)¹⁴. This method would involve increasing the load and reducing the repetitions for muscle groups with a greater percentage of Type IIa or Type IIx fibres and vice versa for muscle groups with greater percentage of Type I fibres. However, little research has yet been undertaken to investigate the feasibility of this training method.

In summary, despite the majority of research findings supporting the classical paradigms of strength and hypertrophy training, more recent studies have proposed that powerlifting-style training may induce equal hypertrophy with greater strength gains compared to bodybuilding-style training. However, there may be instances in which bodybuilding-style training could prove beneficial, particularly in isolation exercises and in novice lifters. Therefore, in order for most lifters to adequately incorporate both methods into their training I would recommend training with heavier loads for fewer repetitions for your primary, compound lifts followed by accessory exercises where lighter loads and more repetitions are performed. However, to conclude, these methods are tools which you can choose to wield and manipulate depending upon your circumstance! And there is no such thing as the ‘optimal’ training method!

by Pete Archibald

PhD Researcher in Regenerative Medicine, Loughborough University

References

1. KRAEMER, W.J. and RATAMESS, N.A., 2004. Fundamentals of resistance training: progression and exercise prescription. Medicine and Science in Sports and Exercise, vol. 36, no. 4, pp. 674-688.

2. BIRD, S.P., TARPENNING, K.M. and MARINO, F.E., 2005. Designing resistance training programmes to enhance muscular fitness. Sports Medicine, vol. 35, no. 10, pp. 841-851.

3. 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.

4. FLECK, SJ., & KRAEMER, WJ., 1997. Designing resistance training programs, 2^nd Ed. Human Kinetics Books, pp. 1-115

5. KRAEMER, W.J., GORDON, S., FLECK, S., MARCHITELLI, L., MELLO, R., DZIADOS, J., FRIEDL, K., HARMAN, E., MARESH, C. and FRY, A., 1991. Endogenous anabolic hormonal and growth factor responses to heavy resistance exercise in males and females. International Journal of Sports Medicine, vol. 12, no. 02, pp. 228-235.

6. BURD, N.A., WEST, D.W., STAPLES, A.W., ATHERTON, P.J., BAKER, J.M., MOORE, D.R., HOLWERDA, A.M., PARISE, G., RENNIE, M.J. and BAKER, S.K., 2010. Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. PloS One, vol. 5, no. 8, pp. e12033.

7. SCHOENFELD, B.J., RATAMESS, N.A., PETERSON, M.D., CONTRERAS, B., TIRYAKI-SONMEZ, G. and ALVAR, B.A., 2014. Effects of different volume-equated resistance training loading strategies on muscular adaptations in well-trained men. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, 20140407, Apr 7 ISSN 1533-4287; 1064-8011. DOI 10.1519/JSC.0000000000000480 [doi].

8. CAMPOS, G.E., LUECKE, T.J., WENDELN, H.K., TOMA, K., HAGERMAN, F.C., MURRAY, T.F., RAGG, K.E., RATAMESS, N.A., KRAEMER, W.J. and STARON, R.S., 2002. Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. European Journal of Applied Physiology, vol. 88, no. 1-2, pp. 50-60.

9. DE VOS, N.J., SINGH, N.A., ROSS, D.A., STAVRINOS, T.M., ORR, R. and FIATARONE SINGH, M.A., 2005. Optimal load for increasing muscle power during explosive resistance training in older adults. The Journals of Gerontology.Series A, Biological Sciences and Medical Sciences, May, vol. 60, no. 5, pp. 638-647 ISSN 1079-5006; 1079-5006. DOI 60/5/638 [pii].

10. HÄKKINEN, K., ALEN, M. and KOMI, P., 1985. Changes in isometric force‐and relaxation‐time, electromyographic and muscle fibre characteristics of human skeletal muscle during strength training and detraining. Acta Physiologica Scandinavica, vol. 125, no. 4, pp. 573-585.

11. MITCHELL, C.J., CHURCHWARD-VENNE, T.A., WEST, D.W., BURD, N.A., BREEN, L., BAKER, S.K. and PHILLIPS, S.M., 2012. Resistance exercise load does not determine training-mediated hypertrophic gains in young men. Journal of Applied Physiology (Bethesda, Md.: 1985), 20120419, Jul, vol. 113, no. 1, pp. 71-77 ISSN 1522-1601; 0161-7567. DOI 10.1152/japplphysiol.00307.2012 [doi].

12. AAGAARD, P., 2003. Training-induced changes in neural function. Exercise and Sport Sciences Reviews, vol. 31, no. 2, pp. 61-67.

13. AAGAARD, P., SIMONSEN, E.B., ANDERSEN, J.L., MAGNUSSON, P. and DYHRE-POULSEN, P., 2002. Increased rate of force development and neural drive of human skeletal muscle following resistance training. Journal of Applied Physiology (Bethesda, Md.: 1985), Oct, vol. 93, no. 4, pp. 1318-1326 ISSN 8750-7587; 0161-7567. DOI 10.1152/japplphysiol.00283.2002 [doi].

14. 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].