This finding has important implications for those who are time-pressed, allowing the ability to get stronger in an efficient manner, and may help to promote greater exercise adherence in the general public. Alternatively, we show that increases in muscle hypertrophy follow a dose–response relationship, with increasingly greater gains achieved with higher training volumes. Thus, those seeking to maximize muscular growth need to allot a greater amount of weekly time to achieve this goal. Further research is warranted to determine how these findings apply to resistance individuals in other populations, such as women and the elderly.
Volume does not appear to have any differential effects on measures of upper-body muscular endurance. When evaluating the results of longitudinal research on the topic, many of the studies have failed to show statistically significant differences in hypertrophy between lower and higher RT volumes. However, low sample sizes in these studies raise the potential for type II errors, invariably confounding the ability to draw conclusive inferences regarding probability.
A recent meta-analysis showed a dose–response relationship between the total number of weekly sets and increases in muscle growth . However, the analysis was only able to determine dose–response effects up to 10 total weekly sets per muscle group due to the paucity of research on higher-volume RT programs. Thus, it remains unclear whether training with even higher volumes would continue to enhance hypertrophic adaptations and, if so, at what point these results would plateau. An added limitation to these findings is that only two of the 15 studies that met inclusion criteria were carried out in individuals with previous RT experience. There is compelling evidence that resistance-trained individuals respond differently than those who are new to RT .
A "ceiling effect" makes it progressively more difficult for trained lifters to increase muscle mass, thereby necessitating more demanding RT protocols to elicit further muscular gains. Indeed, there is emerging evidence that consistent RT can alter anabolic intracellular signaling , indicating an attenuated hypertrophic response. Thus, findings from untrained individuals cannot necessarily be generalized to a resistance-trained population. Other variables that help determine training frequency are intensity and volume.
High-intensity workouts place a significant amount of mechanical stress on muscle tissue and metabolic demands on the anaerobic energy pathways; therefore, fewer reps, sets and training sessions per week should be performed. High-intensity workouts require rest time to allow the nervous system to recover and the muscular system to repair and refuel. Too much high-intensity training in a short period of time could lead to an overuse injury or overtraining. In the original guide, I mentionedthe German Volume study that I reviewed in a past research review.
In this study on trained subjects, 24 weekly sets was not more effective than 14 weekly sets for quadriceps, and 28 weekly sets was not more effective than 18 weekly sets for biceps and triceps. However, it should be noted that many of these sets were not to failure. German Volume Training involves doing 10 sets of 10 with 1 minute rest, and you use the same weight for all sets. In many cases, people can do around 20 reps with 60% 1-RM . In fact, it's difficult to ascertain how many hard sets the subjects did.
Also, it likely varied from one person to the next since it was based on % 1-RM, rather than doing sets to a specific Reps In Reserve . In other words, one person might be able to do a lot more reps than another person with 60% 1-RM, so their initial sets will be much easier. Thus, this study is not a reliable data point for determining where an upper limit may lie.
The same holds true for another 2018 German Volume Study; the methodology was nearly identical, and it again is not reliable for determining an upper limit for volume. It should also be noted that the training frequency was twice per week for upper body, and once per week for lower body in this study. Thus, the highest volume condition was doing 24 sets per session for lower body, greatly exceeding the theoretical 10-set limit. This group was doing 14 sets per session for upper body, again exceeding the theoretical 10-set limit. Thus, the training frequency and per-session volume may also be contributors to the lack of volume effect observed in this study. Three individual studies thus far have used a comparable study design.
Radaelli et al. compared the effects of 6, 18, and 30 weekly sets per muscle group. All groups increased strength postintervention in all four tested exercises. However, for the bench press and lat-pulldown exercises, the 30 weekly set group experienced greater increases than the two other groups. Also, their intervention lasted 6 months, whereas the present study had a duration of 8 wk. It might be that higher training volumes become of greater importance for strength gains over longer time courses; future studies exploring this topic using longer duration interventions are needed to confirm this hypothesis.
Resistance training volume is the amount of total work performed during a session of lifting and is commonly expressed as the product of repetitions X number of sets X intensity load . Any one of these variables can be adjusted to increase volume in a resistance training program. For example, one can increase RTV by performing extra sets of an exercise, adding more repetitions, or increasing the weight being lifted. Exercisers commonly cite "lack of time" as a large barrier to exercise, which explains why low-volume training has gained much popularity (Figueiredo et al., 2017). However, Figueirdo et al. submit that recent publications consistently report that high RTV produces superior muscular adaptations in muscle size (i.e., hypertrophy), which will be the focus of this research column.
Ostrowski and colleagues examined the effects of 1, 2, or 4 sets per exercise on hypertrophy in trained subjects. Subjects did 7-12 reps to failure per set, with 3 minute rests between sets. Triceps were trained twice per week, as pressing movements were performed on one day, and isolation movements were performed on another day. Quadriceps training volume did not exceed 12 total weekly sets since they were only trained once per week.
However, triceps weekly volume, when counting pressing movements, was 7, 14, and 28 for the low, moderate, and high volume groups, respectively. There were no significant differences in changes in triceps thickness between the groups, although the percentage gains and effect sizes favored the groups doing 14 and 28 weekly sets. In fact, percentage gains and effect sizes for weekly sets were about twice that of 7 weekly sets. Marshall et al. examined the effects of three different doses of volume on barbell back squat strength.
Although the authors did include trained men, the main part of the training intervention lasted 6 wk with a twice-weekly frequency, which differs from the present study design. The authors used midpoint testing after 3 wk of training and found that the 8 and 16 weekly set volume groups increased strength from baseline while the two-weekly set group did not. Following the remaining 3 wk, all groups increased strength from their baseline values. However, the 16 weekly set group had greater increases than the 2, but not the eight set group.
In the study by Ostrowski and colleagueson trained subjects, the triceps were subjected to either 7, 14, or 28 weekly sets. Gains nearly doubled moving from 7 to 14 weekly sets, but there was no further increase with 28 weekly sets. Also, bench press performance dropped off with that level of volume. This suggested that perhaps weekly volumes in the high 20's may be more than necessary. However, one limitation of this study, which I did not address in the original version of the guide, is that the researchers did not assess bicep gains.
They also did not do anything beyond 12 weekly sets for quadriceps. Thus, this study is insufficient for determining where an upper limit may lie, as only one muscle group was trained for more than 20 weekly sets. It's also important to note that the training frequency for triceps in this study was two times per week.
Thus, the 28 weekly set condition involved 14 sets per session, exceeding the approximate 10-set per session threshold that we established earlier. Thus, the observed plateau in this study may be due to the frequency. Well, that about does it for the most thorough review on training volume and hypertrophy that you'll find anywhere. You can be sure that this will be updated as new research becomes available. Conclusions in science are always tentative, and based on the best available evidence at the moment. In the case of set volume and hypertrophy, more is better up to around 6-8 hard sets per training session with long rests and twice as much with short rests.
High weekly volumes (20+ weekly sets) give best results when split into frequencies of at least 3 days per week. Of course, this is based on averages, and individuals may respond very differently to changes in volume compared to the average. It's also important to point out that12-18 weekly sets probably gives you the best bang for your buck in terms of hypertrophy relative to the time investment when hitting each muscle 2-3 days per week. If you're looking to do some very high volume training, specialization is the most realistic method of achieving high weekly volumes for a particular muscle group.
Also, regardless of how you program volume,the needs of the individual must be considered. So how might you apply this information to structuring a training program for maximizing hypertrophy? Here's one example of how you might structure a program that uses the best "bang for your buck" range of weekly sets per muscle group. This particular example is a 4-day upper/lower split; most muscle groups are trained via combination of compound and isolation movements. Sets are stopped around 1-2 reps short of failure to allow for better recovery, and repetitions and exercises are varied to help reduce joint stress. In a study of which I was a coauthor, Brad Schoenfeld and colleagues replicated the design of the Radaelli study, but with trained subjects.
The subjects performed 1, 3, or 5 sets per exercise, for 8-12 reps to failure and 1.5 minute rests. Total weekly sets were 6, 18, and 30 for biceps and triceps, and 9, 27, and 45 for quadriceps. A significant dose-response effect was observed in the biceps, rectus femoris , and vastus lateralis . There was not a significant effect for triceps, although the overall pattern had similarities to the other muscles. Resistance exercise stimulates the synthesis of skeletal muscle proteins , , which is eventually expressed as muscle hypertrophy , . It is commonly recommended that high-load contractions (i.e., ≥70% of 1 repetition maximum; 1RM) be performed to provide an optimal stimulus for muscle growth .
It has recently been established, however, that myofibrillar protein synthesis is already maximally stimulated at 60% 1RM, in the post-absorptive state, with no further increase at higher load intensities (i.e., 75–90% 1RM) . Collectively, these data suggest that heavy (i.e., high intensity) external loads are not a prerequisite to elicit increases in muscle protein synthesis and ultimately muscle hypertrophy , , . By selecting 2-4 chest exercises per workout you can add 4-8 different chest exercises per training program, which is plenty of variation in a month's time. Instead, stay within those ranges and work to perform quality repetitions with a hyper-focus mindset of feeling the chest muscles stretch throughout the full range of motion.
The study had several limitations that must be taken into account when attempting to draw evidence-based inferences. First, all subjects reported performing multiset routines before the onset of the study and a majority did not regularly train to momentary failure. It is unclear how the novelty of altering these variables affected the respective groups. Second, the upper-body musculature was trained exclusively with multijoint exercises. These exercises involve extensive involvement of the elbow flexors and elbow extensors, as shown in the significant arm muscle hypertrophy achieved with their consistent use .
Indeed, research indicates similar changes both in upper arm MT and circumference when performing multijoint versus single-joint exercises in untrained and trained individuals, respectively . That said, it remains possible that single-joint exercises for the arm musculature may become more important to hypertrophy when training with low volumes; further study on the topic is warranted. Third, measurements of MT were obtained only at the mid-portion of the muscle belly. Fourth, although subjects were instructed not to perform any additional exercise training during the study, we cannot entirely rule out that they failed to follow our guidelines. Fifth, the study had a relatively small sample size and thus may have been somewhat underpowered to detect significant changes between groups in certain outcomes.
Sixth, while ultrasound is a well-established method of assessing changes in markers of muscle hypertrophy, it is not clear how the magnitude of the reported changes impact aesthetic appearance. Finally, findings of our study are specific to young resistance-trained men and, therefore, cannot necessarily be generalized to other populations, including adolescents, women, and older adults. In conclusion, we have demonstrated that low-load high volume resistance exercise has a potent stimulatory effect on anabolic signalling molecules, MyoD and myogenin mRNA expression and muscle protein synthesis.
Our results support previous findings that demonstrated after 16 weeks of isometric training at 30% maximal voluntary contraction that significant increases in fibre area can be achieved . Training for all routines consisted of three weekly sessions performed on nonconsecutive days for 8 wk. Sets consisted of 8 to 12 repetitions carried out to the point of momentary concentric failure, that is, the inability to perform another concentric repetition while maintaining proper form. The cadence of repetitions was carried out in a controlled fashion, with a concentric action of approximately 1 s and an eccentric action of approximately 2 s.
The time between exercises was prolonged to approximately 120 s given the additional time required for the setup of the equipment used in the subsequent resistance exercise. The load was adjusted for each exercise as needed on successive sets to ensure that subjects achieved momentary failure in the target repetition range. All routines were directly supervised by the research team to ensure proper performance of the respective routines. Attempts were made to progressively increase the loads lifted each week to ensure that the subjects were exercising with as much resistance as possible within the confines of maintaining the target repetition range. Before training, subjects underwent 10 repetition maximum testing to determine individual initial training loads for each exercise. Repetition maximum testing was consistent with recognized guidelines as established by the National Strength and Conditioning Association .
What Is Overfill Volume Hypertrophy occurs along a spectrum of volumes, so trainers are encouraged to undulate low, moderate, and high-volume programs to increase adherence and prevent overtraining with their clients. For instance, 1-2 set training can be used for a recovery block and 3-5 set training can be utilized for blocks of overload and/or overreaching. The research strongly suggests that RTV is the primary driver for hypertrophy, and higher-volume programs generally result in greater muscle growth. However, the relationship between RTV and hypertrophy may be described as an inverted U-shape, meaning that adaptations diminish when too few or too many sets are performed. Therefore, it follows that enthusiastic lifters may best optimize muscular hypertrophy adaptations by performing multiple sets not exceeding 5 sets per exercise . Wackerhage et al. add that for optimal hypertrophy, clients should train at 40-80% of their 1-repetition maximum, using loads greater than 60% if strength is also a target goal.
Wackerhage and colleagues also summarize research indicating to rest over 2 minutes between sets, and consume a diet that contains at least 1.6 grams of protein per kilogram of body weight. Upper- and lower-body strength was assessed by 1RM testing in the barbell parallel back squat and flat barbell bench press exercises. These exercises were chosen because they are well established as measures of maximal strength. Subjects reported to the laboratory having refrained from any exercise other than activities of daily living for at least 48 h before baseline testing and at least 48 h before testing at the conclusion of the study. RM testing was consistent with recognized guidelines established by the National Strength and Conditioning Association . In brief, subjects performed a general warm-up before testing that consisted of light cardiovascular exercise lasting approximately 5 to 10 min.
Subjects then performed sets of one repetition of increasing weight for 1RM determination. Three- to 5-min rest was provided between each successive attempt. Successful 1RMBENCH was achieved if the subject displayed a five-point body contact position and executed full-elbow extension. 1RMSQUAT testing was conducted before 1RMBENCH with a 5-min rest period separating tests. Recording of foot and hand placement was made during baseline 1RM testing and then used for poststudy performance.
All testing sessions were supervised by the research team to achieve a consensus for success on each trial. The repeatability of strength tests was assessed on two nonconsecutive days in a pilot study of six young, resistance-trained men. The ICC for the 1RMBENCH and 1RMSQUAT was 0.98 and 0.93, respectively. The SEM for these measures are 2.0 and 2.4 kg, respectively. This notion is supported by data which demonstrated that aged muscle (∼70 years) has an 'anabolic resistance' to resistance exercise and this resistance may be overcome with increased volume of exercise . However, it is important to recognize that acute scientific studies simply supply the framework on which to build future training studies upon to directly test if a cause-and-effect relationship does in fact exist.
Why does multiple-set training evoke greater hypertrophy than single-set training? Muscle hypertrophy is a multifaceted process which has not been completely explained in research. However, mechanical load, that is the weight lifted, is arguably a key and perhaps the most important mechanism activating muscle hypertrophy . A high RTV exercise stimulus produces sustained mechanical tension on the muscles, which potentially increases the post-exercise activity of intracellular molecules responsible for increasing muscle protein synthesis. Mitchell et al. discuss that a possible mechanism is with the protein p70S6K.
