How long should the break between sets last – hypertrophy vs strength?

According to the common beliefs, a strength-building workout contains long breaks lasting many minutes between the sets. Whereas, the hypertrophic training includes more repetitions and shorter breaks between sets. As it has been pointed out many times in the scientific studies, such statements don't have to be true. Why? For example, beginners react perfectly with the increase of strength during a seemingly typical “hypertrophic” bodybuilding workout (within 8-15 repetitions), there are also many representatives of the powerlifting or biathlon training, who developed their postures within 3-6 repetitions. As if it wasn't enough, beginners notice the hypertrophic effects after... interval training.

Examples:

  • Dymitry Klokov, an outstanding Russian weightlifter – performed during the weight-lifting competitions, and his silhouette is a role model for thousands of people,

  • Svend Karlsen as an anti-bodybuilding powerlifter – won the bodybuilding competitions (then he became a famous strongman, champion of the World's Strongest Man in 2001),

  • Arnold Schwarzenegger (7 times Mr Olympia) primarly started in weight-lifting, although the information about that is incomplete (the years of 1963-1965),

  • Arnold Schwarzenegger won the international powerlifting competition on 30th October 1966, achieving 170 kg in squat, 165 kg in bench press, 250 kg in deadlift [2, 3],

  • Arnold Schwarzenegger at the age of 19, in 1967, performed in the powerlifting competition in Munich, he was the runner-up, he scored the bench press with 170 kg (374 lbs), squat with 200 kg (440 lbs) and deadlift with 280 kg (616 lbs); Attention, according to the wrong information from the “Flex” magazine published in 2005, that competition was supposed to take place in 1966,

  • Arnold Schwarzenegger in his last powerlifting competition on 5th May 1968 scored squat with 215 kg, bench press with 200 kg and deadlift with 310 kg [2, 3], which made him the winner,

  • Ronnie Coleman – one of the best bodybuilders of all times (8 times Mr Olympia) – started his journey with resistance sports with the competition in deadlift, he lifted 330 kg in 1994 in Texas [4],

  • Morgan Aste – one of the strongest bodybuilders of all times, takes part in the strongman competitions (among others, he scored 6 x 250 kg on a bench, without the T-shirt and 360 kg in the Farmer's walk),

  • Robert Burneika – one of the most famous bodybuilders online – at first he did bench press and performed in the strongman competition.

What can be found in research about that?

In the study from 2014 (Schoenfeld BJ) [1] in the hypertrophy group: 3 sets with 10 repetitions with 90-second break, and strength group: 7 sets with 3 repetitions with 3-minutes break, the results were the same – in squat and bench press, as well as the arm circumference were similar (with slight advantage of the increase of strength for people doing 3 repetitions instead of 10 in one set).

Results?

  • Strength group improved bench press by 13%,

  • bodybuilding group improved bench press by 9.1%,

  • squat: the strength group improved by 25.9%, whereas, in the bodybuilding group the improvement was by 22.2%,

  • the size of the arm: the strength group at the beginning: 35.3 +/- 5.7cm, at the end: 39.6 +/- 5.1cm (increase by 12.7%),

  • the size of the arm: the bodybuilding group at the beginning: 34.5 +/- 4.2cm, at the end: 38.7 +/- 4.3 cm (increase by 12.6%).

In the Willardson JM and Burkett's study (2008) [5], there was the comparison of two- and four-minute breaks between the sets during few training mesocycles among 15 men. They were well-trained competitors (they had done squats for at least 4 years), at the age of 20-23, height: 180-182cm, weight: 82-92kg (on average). The men were checked four times concerning the squat, close to the bodybuilding one, the barbell was on the quadriceps. The limit was used, which pointed appropriate depth of the squat in each case.

The men did the same exercise program – mesocycle:

  • Week 1: test MAXIMUM, deep squats,

  • Week 2: 8 sets with the load of 70% of the maximal load, 11-15 repetitions

  • Week 3: 7 sets with the load of 80% of the maximal load, 6-10 repetitions,

  • Week 4: 6 sets with the load of 90 % of the maximal load, 3-5 repetitions,

  • Week 5: test MAXIMUM, deep squats,

  • Weeks 6-8: repetition of the mesocycle,

  • Week 9: test MAXIMUM, deep squats,

  • Weeks 10-12: repetition of the mesocycle,

  • Week 13: test MAXIMUM, deep squats.

The only difference was the break between the sets of 2 or 4 minutes. What's more interesting, the differences between the men were not important. Below, you can find the results of the maximal squat in the following tests in week 1, 5, 9 and 13 of the experiment.

In the group with 2 minutes of break between the sets:

  • Test no. 1: squats: 145.13 +/- 24.17 kg,

  • Test no. 2: squats: 156.82 +/- 22.88 kg,

  • Test no. 3: squats: 162.34 +/- 22.26 kg,

  • Test no. 4: squats: 171.43 +/- 25.34 kg.

In the group with 4 minutes of break between the sets:

  • Test no. 1: squats: 150.00 +/- 18.54 kg,

  • Test no. 2: squats: 162.78 +/- 19.28 kg,

  • Test no. 3: squats: 172.73 +/- 18.42 kg,

  • Test no. 4: squats: 182.10 +/- 21.44 kg.

The most important difference was that the group with 4-minute break between the sets of squats had higher training volume (during the “hard” sessions).

Older metanalyses of studies claim [7], that shorter breaks between sets are more advantagous for the hypertrophy because of the increase of excretion of the growth hormone. Unfortunately, the studies published on 20th November 2015 (Schoenfeld BJ) bring another picture of the situation. 21 men well-trained in strength were randomly divided into groups of “short rest” (1-minute break between the sets) or “long rest” (3 minutes). During 8 weeks the men did the same resistance training, which included 3 sets of 8-12 repetitions of 7 various strength exercises.

The following were checked:

  • results of bench press (1 repetition at most),

  • results of squat (1 repetition at most),

  • muscle endurance (bench press concerning the amount of repetitions, with 50% of maximal load),

  • the thickness of arm flexor (among others, biceps), method: ultrasound,

  • the thickness of triceps (ultrasound),

  • the thickness of quadriceps (ultrasound).

Results?

  • Maximal strength was significantly higher in the long break group (3 minutes) between the sets, comparing to the short break (1 minute),

  • there were higher build-ups in the group with long break between the sets in the front part of the thigh and in triceps,

  • both groups increased the local muscle endurance (with no difference between the groups).

In the next study [8] published on 13th August 2015 – 33 physically active men were divided into groups. In the volume group there were the following parameters of training:

  • load: 70% of the maximal load,

  • 4 sets of 10-12 repetitions,

  • 1-minute break between sets.

In the intensity group there were the following parameters of training:

  • load: 90% of the maximal load,

  • 4 sets of 3-5 repetitions,

  • 3-minute breaks between sets.

Results:

  • in bench press, the intensity group improved by 14.8 +/- 9.7%, whereas, in the volume group by 6.9 +/- 9.0%,

  • lean arms mass (muscles) – in the intensity group improved by 5.2 +/- 2.9%, in the volume group by 2.2 +/- 5.6%,

  • lean body mass (muscles) – in the volume group: before – 68.5 kg, after – 68.6 +/- 7.9 kg,

  • lean body mass (muscles) – in the intensity group: before – 68.5 kg, after – 69.9 +/- 7.5 kg.

Final conclusions:

  • it's impossible to define if shorter break between the sets will cause the increase of muscle mass, paradoxically, many studies do not confirm this thesis,

  • even for the improvement of the results in strength exercises (squat, bench press, pull-ups) the results are ambiguous,

  • it can be assumed, that the optimal break between the sets for the small muscles training, such as biceps, triceps, shoulders, forearm, it is 40-90 seconds, hypertrophy,

  • the more isolated and short movement, the shorter the rest break may be,

  • it can be assumed that the optimal break between the sets for the large muscles training (back, legs, ABS), it is 120-180 seconds, hypertrophy,

  • for sports people who lift extreme weights with the powerlifting equipment (T-shirt for bench press, bandages for squats, costumes for deadlift), the breaks between the sets of the maximal attempts may last even 5-7 minutes, it concerns people lifting e.g. 230-300% of body weight in MC, 200-300% of body weight in squats or 160-220% of body mass in bench press,

  • for the reduction of body mass in the interval training with load, the advantagous break between the sets is the shortest possible (incomplete rest),

  • sports people using AAS may, on the one hand, attempt further sets earlier, however, if they use heavier working load, this advantage is corrected.

Sources: 1. http://www.ncbi.nlm.nih.gov/pubmed/24714538 J Strength Cond Res. 2014 Oct;28(10):2909-18. doi: 10.1519/JSC.0000000000000480. Effects of different volume-equated resistance training loading strategies on muscular adaptations in well-trained men. 2. http://www.getbig.com/ 3. http://www.gmv.com.au/default.asp?pageid=home&template=content&sid=283 4. http://potreningu.pl/articles/4127/czy-trening-typu-trojbojowego-nadaje-sie-dla-kulturysty 5. J Strength Cond Res. 2008 Jan;22(1) “The effect of different rest intervals between sets on volume components and strength gains.” 6. J Strength Cond Res. 2015 Nov 20. “Longer inter-set rest periods enhance muscle strength and hypertrophy in resistance-trained men”. http://www.ncbi.nlm.nih.gov/pubmed/26605807 7. Sports Med. 2009;39(9):765-77. doi: 10.2165/11315230-000000000-00000. “Rest interval between sets in strength training.” 8. http://potreningu.pl/articles/4296/objetosc-czy-intensywnosc-dla-maksymalnych-efektow-sily-i-masy