Recent studies have shown some controversial findings that high-rep training is as effective as the traditional medium rep training for muscle growth. If you missed it, check out my two previous articles:
In this article I will show some examples of how high-rep sets can be implemented in a serious weight lifting program, and look at the results of some studies that have investigated this.
Periodized weight training and training variety – a necessary strategy for continued progress
I will save an in-depth discussion on periodized weight training for a separate article. The take home from studies on periodized weight training is that training periodization, or variation, is key for breaking through training plateaus and for making continued progress in both strength, power and muscle growth 1. Benefits with periodized weight training have been seen in both beginners 1-4 and experienced athletes 1, 2, 5-9, but it is especially critical for advanced weight lifters, bodybuilders and other athletes.
Training periodization can be accomplished in many ways; the training variables that are most commonly manipulated are intensity (weight lifted and number of repetitions), number of sets, rest between sets, and lifting speed. In this article I will cover training intensity and lifting speed, since these training variables are directly related; the slower you lift the lighter the weights you can move, and vice versa.
High-rep finishing sets after heavy, high intensity workouts in a periodized training program – how does it affect gains in muscle mass and strength?
An interesting study investigated muscular adaptations to a combination of high- and low-intensity resistance exercise in a periodized training program 4.
The following 3 different types of workouts were tested:
- Hypertrophy type
9 sets of medium intensity (10 repetition maximum [RM]) short inter-set rest period (30 s) with progressively decreasing load.
- Strength type
5 sets of a high-intensity (90% of 1RM) and low-repetition exercise.
1 set of low-intensity and high-repetition exercise added immediately after the last (5th) set in the strength-type regimen.
The hypertrophy type phase consisted of nine sets at 80–40% of 1RM. The each workout was divided into three parts with three sets each, and the rest periods between sets and parts were 30 seconds and 3 minutes, respectively. In each part, the intensity was gradually lowered set-by-set (multi-poundage or descending set system).
The diagrams below outline the training periodization, and the workout protocol in each phase.
The subjects were young men (20-23 years) with a couple of months of recreational resistance training experience, but they had not taken part in any regular training program for at least 6 months prior to the study.
Before the start of the 10 week training program, acute changes in blood levels of growth hormone (GH) were measured after one bout single of each workout type, using leg extension. As illustrated in figure 2, there were significant differences in post-exercise increases in GH levels: hypertrophy-type > combi-type > strength-type.
Next, the long-term effects of a periodized training protocols with these different types of workouts was conducted. The subjects were assigned to either a hypertrophy/combi (HC) or hypertrophy/strength (HS) group and performed leg press and extension exercises twice a week for 10 weeks.
During the first 6 weeks, both groups used the hypertrophy-type training to gain muscular size.
During the subsequent 4 weeks, the HC group performed combi-type training, and the HS group performed strength-type training.
Muscular strength, endurance, and cross sectional area (muscle size) were examined.
After the initial 6 weeks, no significant between group differences was seen in the percentage changes in any of these outcomes.
However, after the subsequent 4 weeks, 1RM of leg press and muscular endurance of leg extension showed significantly larger increases in the HC group than in the HS group. In addition, increases in muscle growth (cross sectional area) after this period also tended to be larger in the HC group than in the HS group. It was also found that adding low-intensity high-repetition set didn’t interfere with neuromuscular adaptations 4.
Lifting speed and time under tension – another variable to consider in high-rep sets
High-rep sets differ from low-rep sets in that they allow more control of lifting (repetition) speed, due to the lower weight lifted. And lifting speed deserves way more attention than it has been getting…
Lifting speed is important because it determines time under muscle tension, which is the amount of time muscles must contract to complete a set. According to the most successful strength coach in the world, Charles Poliquin, to develop maximum muscle mass, the muscles should contract 20-70 seconds during a set 10.
Am interesting recent study compared the effects of difference lifting speeds on synthesis of different muscle protein fractions 11. The subjects (recreationally resistance-trained young men) did an exercise bout consisting of 3 sets of unilateral leg extension (one leg lifting slow, the other fast), at 30% 1RM, with 2 min rest between sets:
Slow lifting speed: 6 seconds up and 6 seconds down, no pauses until failure
Fast lifting speed: 1 second up and 1 second down, no pauses
The fast lifting speed condition was matched to the slow condition for contraction volume (meaning that the leg performed an identical number of reps at the same load), but not to failure.
Participants ingested 20 g whey protein immediately after the exercise bout. The number of repetitions performed was 12, 7 and 6 for set 1, 2 and 3. As planned, the muscle time under tension (measured in seconds) was greater for each set in the slow condition compared to the fast:
Slow lifting speed time under tension: set 1 – 144 s (12×12); set 2 -84 s (12×7) and set 3 – 72 s (12×6)
Fast lifting speed time under tension: set 1 – 24 s (2×12); set 2 -14 s (2×7) and set 3 – 12 s (2×6)
The interesting finding in this study was that myofibrillar protein synthetic rate was about 30% higher in after the slow lifting speed bout versus the fast lifting speed bout after 24-30 h recovery, and correlated to p70S6K phosphorylation (which is a marker for anabolism and hypertrophy 12). The slow lifting speed bout also significantly increased both sarcoplasmic and mitochondrial protein synthesis rate 6 hours post-exercise, compared to the fast lifting speed bout.
A slightly faster lifting speed than used in this study, 3 s up and 3 s down (this is still slower than the usual 1 s up – 1 s down), with a slightly heavier load (around 40-50% of max strength) would be more anabolic towards the myofibrillar fraction (which is the muscle protein fraction that is responsible for muscle growth) 13. This agrees nicely with Poliquin’s suggestion that muscles should contract 20-70 seconds during a set to develop maximum muscle mass.
Another study compared a slow lifting speed of 3 seconds up and 3 seconds down at an intensity of 40% 1RM to failure, with a fast lifting speed of 1 second up and 1 second down at an intensity of 80% 1RM to failure, in 5 sets of leg extension 14. The subjects were heavy-resistance exercise trained young men. A striking finding in this study was that the slow lifting speed bout resulted in almost a 3 fold higher elevation in free testosterone than the fast lifting speed bout 14.
It has also been shown that low-intensity exercises with different slow lifting speeds on the up (concentric) and down (eccentric) phases of contractions (3 s up – 3 s down, 5 s up – 1 s down, 1 s up – 5 s down) all significantly result in greater GH elevation compared to fast lifting speeds (1 s up – 1 s down), regardless of the time to complete up and down actions 15.
Finally, there are indications that going faster on the lowering (eccentric) part of contractions than the lifting (concentric) part, leads to greater hypertrophy and strength gains than slow lengthening contractions 16.
Bottom line, lighter high rep sets with slow lifting speeds, when taken to failure, are not a waste of time in the gym, like many bodybuilders and strength athletes think. To the contrary, lighter high rep sets with slow lifting speeds add two new training variables to your workout, which can help you to break through training plateaus and boredom that arise from constantly doing the same thing in the gym. Thereby, high reppers and sets with slower lifting speeds will help ensure continuous training progress and propel you towards your weight lifting goals.
Monica has a Bachelor’s and Master’s degree in Nutrition from the University of Stockholm, Sweden, and is an ISSA Certified Personal Trainer. She works a nutrition/diet consultant and health journalist, and is also a fitness model and web designer.
As a young athlete, Monica realized the importance of nutrition for maximal performance at an early, and went for a major in Nutrition at the University of Stockholm.
During her years at the University she was a regular contributor to the Swedish bodybuilding magazine BODY, and she has written the book (in Swedish) “Functional Foods for Health and Energy Balance”, and authored several book chapters in Swedish publications. During her University studies she also worked as an ISSA certified personal trainer.
After having earned her Bachelor’s and Master’s degree in Nutrition, she completed one semester at the PhD-program “Exercise, Nutrition and Preventive Health” at Baylor University Texas, at the department of Health Human Performance and Recreation.
Having lost her father in an heart attack at an age of 49, she is specializing in cardiovascular health, and primordial and primary prevention. She is a strong advocate of early intervention in adolescence and young adulthood, and the importance of lifestyle habits for health promotion at all ages.
Today, Monica is sharing her solid academic and real-life experience by offering nutrition/diet and exercise consultation services and writing about topics related to fitness, health and anti-aging.
15. Goto K, Ishii N, Kizuka T, et al. Hormonal and metabolic responses to slow movement resistance exercise with different durations of concentric and eccentric actions. European journal of applied physiology. 2009;106(5):731-739.
16. Shepstone TN, Tang JE, Dallaire S, et al. Short-term high- vs. low-velocity isokinetic lengthening training results in greater hypertrophy of the elbow flexors in young men. J Appl Physiol. 2005;98(5):1768-1776.
17. Rhea MR, Ball SD, Phillips WT, et al. A comparison of linear and daily undulating periodized programs with equated volume and intensity for strength. Journal of strength and conditioning research / National Strength & Conditioning Association. 2002;16(2):250-255.
18. Bak JF, Moller N, Schmitz O. Effects of growth hormone on fuel utilization and muscle glycogen synthase activity in normal humans. The American journal of physiology. 1991;260(5 Pt 1):E736-742.
19. Moller J, Jorgensen JO, Moller N, et al. Effects of growth hormone administration on fuel oxidation and thyroid function in normal man. Metabolism: clinical and experimental. 1992;41(7):728-731.
20. Moller N, Jorgensen JO, Alberti KG, et al. Short-term effects of growth hormone on fuel oxidation and regional substrate metabolism in normal man. The Journal of clinical endocrinology and metabolism. 1990;70(4):1179-1186.
21. Moller N, Jorgensen JO, Schmitz O, et al. Effects of a growth hormone pulse on total and forearm substrate fluxes in humans. The American journal of physiology. 1990;258(1 Pt 1):E86-91.
22. Moller N, Schmitz O, Porksen N, et al. Dose-response studies on the metabolic effects of a growth hormone pulse in humans. Metabolism: clinical and experimental. 1992;41(2):172-175.