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Determining Appropriate Set Volume for Resistance Exercise


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Determining Appropriate
Set Volume for
Resistance Exercise
James Krieger, MS
Journal of Pure Power, Redmond, Washington
The design of a resistance train-
ing program requires the ap-
propriate manipulation of a
variety of variables, all of which can
affect the adaptations to a resistance
training program. These variables in-
clude but are not limited to frequency,
intensity, and volume. A primary way
that training volume can be manipu-
lated is through the number of sets
performed per exercise and per muscle
group. Thus, the number of sets can
have a strong impact on the morpho-
logical and performance-based outcomes
of a resistance training program. The
response of the body to changes in set
volume can be viewed as a dose-
response relationship. For example, as
the dose of a drug is increased, the
body’s response to that drug increases,
until a plateau is reached. If the drug
dose continues to increase, there is
no further increase in the body’s re-
sponse to the drug, but an increase in
side effects can occur. Similarly, as the
number of sets of a resistance exercise
increases, the body’s response (the
increase in strength and muscle mass)
may increase. However, at some point,
this response will plateau, and too many
sets may increase the risk of injury.
The personal trainer should take an
evidence-based approach when it comes
to program design for a client. How-
ever, the evidence regarding the
appropriate number of sets has not
been straightforward. Review articles
on this topic have come to different
conclusions as to whether multiple sets
can produce superior strength gains
(1,3,4,23). Most studies published over
the past decade have shown multiple
sets to result in significantly greater
strength gains than single sets (2,5–9,
12–14,17,20,21). Some published meta-
analyses indicate multiple sets to be
superior (18,19,24); however, these
articles have a number of methodo-
logical limitations, which has resulted
in criticism of their conclusions (10,16).
Also, the results of these articles have
not been consistent. For example, Rhea
et al. (19) reported multiple sets to be
superior in both trained and untrained
subjects, but Wolfe et al. (24) reported
multiple sets to be superior in trained
subjects only.
Another problem is that the majority
of resistance training studies compare
1 set with 3 sets per exercise (1,4).
However, there are many other varia-
tions in set volume that can be pre-
scribed. There has been very little
research done regarding the dose-
response effects of the number of sets
on strength gains. Ostrowski et al. (15)
compared 1, 2, and 4 sets per exercise
and reported no significant differences
between groups. However, the vari-
ability of the responses and the small
number of subjects per group limit the
statistical power to detect differences
between groups. Rhea et al. (19) looked
at dose-response effects with a meta-
analysis, reporting 4 sets per muscle
group to be the optimal number for
both trained and untrained subjects.
However, as mentioned earlier, the
limitations of the study design indicate
that the results should be interpreted
with caution. Also, since Rhea et al.
reported the data as sets per muscle
group, the sets-per-exercise problem is
not adequately addressed. Given the
lack of convincing scientific data re-
garding the dose-response effects of
the number of sets, it can be difficult for
the personal trainer to decide what
number is appropriate for a client.
A recent meta-analysis was published in
the Journal of Strength and Conditioning
volume; sets; strength; meta-analysis
VOLUME 32 | NUMBER 3 | JUNE 2010 Copyright ÓNational Strength and Conditioning Association
Research to try to shed more light on
the dose-response effects of the num-
ber of sets per exercise (10). This meta-
analysis had 2 purposes: to address the
criticisms of previous meta-analyses in
this area and to establish a dose-re-
sponse relationship of set volume on
strength. The main finding was that
a single set per exercise resulted in
strength gains, but multiple sets were
superior. Specifically, 2–3 sets per
exercise was associated with 46%
greater strength gains than 1 set, and
no further benefit was observed for
more than 3 sets. These findings
applied to both trained and untrained
subjects, upper- and lower-body exer-
cises, and a variety of training frequen-
cies. These findings were also true
whether or not multiple exercises were
performed per muscle group.
The main limitation of this recent
analysis is that there were only 2 stud-
ies included that incorporated 4 or
more sets per exercise. This limits the
statistical power to detect significant
differences. It is still possible that 4 or
more sets could result in greater
strength gains than 2–3 sets, but more
research in this area will be needed to
answer this question. What is apparent
is that there is a plateau in strength gains
once you get to 4–6 sets per exercise;
2–3 sets resulted in 46% greater gains
than 1 set, whereas 4–6 sets only
resulted in 13% greater gains than
2–3 sets. The reason for this plateau
is not currently known. It is known that
mechanical loading stimulates protein
synthesis in skeletal muscle (22), and
increasing loads result in greater re-
sponses until a plateau is reached (11).
It is likely that protein synthesis responds
in a similar manner to the number of
sets (i.e., an increasing response as the
number of sets are increased, until a
plateau is reached), although there is
no research examining this.
The findings of this analysis allow for
a number of practical applications
that personal trainers can use in their
program designs:
1. If a client is only interested in
general fitness and does not need
maximal gains in strength, then 1 set
per exercise is a sufficient stimulus to
improve strength. Also, clients who
are lacking time can still experience
strength gains by doing only 1 set to
failure or near-failure per exercise.
2. If a client is interested in maximal
strength gains, then multiple sets per
exercise are necessary. Because the
majority of studies in this meta-
analysis compared 1 set with 3 sets
per exercise, than 3 sets per exercise
is an appropriate starting point for
a client. Because these numbers are
based on averages, individual client
responses may vary. Thus, set vol-
ume can be adjusted up or down
from this starting point based on
client response and tolerance.
3. The point of diminishing returns
appears to be above 3 sets per exer-
cise. In this meta-analysis, 4–6 sets
per exercise was not significantly
different from 2–3 sets. Thus, there is
little additional benefit to doing more
than 3 sets per exercise, although
individual responses may vary.
4. There is no need to differentiate
between trained and untrained sub-
jects in regards to set volume; both
are equally likely to benefit from
multiple sets. However, for clients
with little resistance training expe-
rience, it is probably prudent to keep
initial volume to 1–2 sets per exer-
cise to help prevent the delayed-
onset muscle soreness that usually
accompanies unaccustomed exercise.
Set volume can then be progressed.
5. These set volumes are considered
work sets and do not include warm-
up sets.
There are still questions that science
needs to answer regarding program
design. For example, is it beneficial to
incorporate multiple exercises target-
ing the same muscle group? The recent
meta-analysis found no benefit to
doing multiple exercises, although it
was not specifically designed to answer
this question. Also, more research is
needed looking at dose-response rela-
tionships in regards to the number of
sets; there are very few studies that use
volumes of more than 3 sets per
exercise (13,15). Another question that
needs to be answered is the
relationship between the number of
sets and intensity. The studies in the
recent meta-analysis involved an aver-
age of 7–10 repetition maximum (RM)
per set. The optimal set volume for
higher training intensities (1–5 RM)
has not been adequately investigated.
Although scientists have more to in-
vestigate regarding other topics, the
evidence in the single versus multiple
set debate overwhelmingly favors mul-
tiple sets. It is also clear that there is a
dose-response relationship in regards
to set volume and strength, with an
apparent plateau in the response be-
yond 3 sets per exercise. Clients who
want maximal strength gains are best
off doing 2–3 sets per exercise, whereas
clients who just want to stay fit or lack
time can achieve moderate strength
improvements with a single set. It
should also be noted that these con-
clusions are limited to general fitness
and maximal strength and that the
appropriate set volume may be differ-
ent for other goals such as hypertro-
phy, power, and endurance. As always,
a personal trainer should tailor a client’s
program to his/her individual needs,
goals, and limitations.
James Krieger
is the editor for
Journal of Pure
Power, an online
publication that
delivers science-
based informa-
tion in a manner
easy to under-
stand by athletes
and coaches.
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VOLUME 32 | NUMBER 3 | JUNE 2010
Determining Appropriate Set Volume for Resistance Exercise
... In a recent review entitled Determining Appropriate Set Volume for Resistance Exercise [4], Krieger stated that the primary way to manipulate the volume of training is to increase or decrease the number of sets for each exercise. In his next sentence he claimed: "Thus, the number of sets can have a strong impact on the morphological and performance-based outcomes of a resistance training program" (p. ...
... In Krieger's review [4], he summarized and cited his own meta-analysis entitled Single Versus Multiple Sets of Resistance Training: A Meta-regression [5]. Although there are subtle differences between a meta-analysis and a meta-regression, Krieger never explained these differences in his mega-regression and several times in his review [4] he referred to his hierarchical, random-effects meta-regression simply as a meta-analysis. ...
... In Krieger's review [4], he summarized and cited his own meta-analysis entitled Single Versus Multiple Sets of Resistance Training: A Meta-regression [5]. Although there are subtle differences between a meta-analysis and a meta-regression, Krieger never explained these differences in his mega-regression and several times in his review [4] he referred to his hierarchical, random-effects meta-regression simply as a meta-analysis. Therefore to maintain consistency with Krieger's own description, this Critical Review will refer to his meta-regression as a meta-analysis. ...
Full-text available
A meta-analysis is a controversial statistical procedure that combines the data from several independent studies in an attempt to produce an estimate for the effectiveness of a specific intervention. The validity of a meta-analysis, also known by its critics as numerological abracadabra, is dependent on the arbitrarily defined criteria and discrimination of the analyst, and more importantly, on the quality of the inclusive studies. The focus of this commentary is a meta-analysis by Krieger, who claimed that multiple sets of each exercise are superior to a single set of each exercise for increasing muscular strength. Some examples of the inclusive studies that he awarded the highest quality scores are shown in this Critical Review to be very poor quality studies and not acceptable for inclusion in a meta-analysis.
... Training volume can be altered in a number of ways: varying reps in a set, resistance in rep, number of sets, and frequency of training [8,[15][16][17][18]. Several investigators have examined the number of sets for resistance training to develop strength [10,14,19,20]. ...
... Although we demonstrated modest improvements in lower body power with a program of similar volume but less duration, perhaps a longer duration with either the 2-set or 4-set interventions would have resulted in greater achievement. We implemented a program in which we maintained the same number of sets but we alternated the relative resistances in a pyramid design [11,17,22]. Alternative approaches that can address dose-response relationships by utilizing intensity, repetitions and/or duration would be useful for understanding the application of resistance plyometric training [10,11]. ...
... Lower-body power development is an important factor for many athletic maneuvers [22]. The present results supports the evidence regarding the efficacy of plyometric programs composed of larger number of sets [12,17,18,22]. Of course, several training strategies can be used to enhance lower body power performance [11], but the findings of this study suggesting that 4 sets, for 8 weeks and 3 times per week are enough for modest improvements in jumping performance. ...
Full-text available
Training volume and the number of sets for developing lower body explosive power are important considerations for plyometric training. The purpose of this study was to compare training volume differing in number of sets in a 8-week program on field-based measures of lower-body explosive power. We hypothesized plyometric training would enhance lower body explosive power in a dose-dependent manner in which a 4-set program would result in greater power improvements than a 2-set program. Seventy-two recreational exercisers were randomly assigned to one of 3 groups: 2-set, 4-set or non-plyometric control. Controls exercised ad libitum with the exception of any plyometric exercise. Training by experimental groups included weighted static jumps (SJ) and countermovement jumps (CMJ) using heavy and light loads, under a supervised and periodized program for 3 d/wk over 8 wks. Heavy loads were ramped up by 10% of one-repetition maximum (1RM) each week starting from 60% of 1RM, followed by a light load of 30% of 1RM for 8 repetitions for the first 4 wks of training. During the last 4 wks, the heavy loads were ramped down by 10% of 1RM each week starting from 90% of 1RM. The executed repetitions for the heavy loads for each week and each work-out day were periodized from 4 to 50 repetitions. Lower-body power was measured before and after using a commercial-available contact mat that recorded the ground reaction forces. The dependent variables were vertical jump height (H) and power (PW) of SJ and CMJ. One-way analyses of variance with paired post-hoc analysis on mean post-pre differences were employed to determine significant effects (p < 0.05). Improvement in SJ-H (p = 0.0099), SJ-PW (p = 0.0208), CMJ-H (p = 0.0037), CMJ-PW (p = 0.0037) were all greater in 4-set group when compared to 2-set and control groups. The 2-set group did not differ from the control in any of the dependent variables. Plyometric training does not always improve explosive power. A periodized resistance plyometric program varied by exercise sets demonstrated that a greater training volume is necessary for developing lower-body explosive power. An effective way to increase plyometric training is to increase the number of sets.
... The interest in the effect training volume on strength and hypertrophy has resulted in several meta-analyses and reviews on this topic. Some reviews and metaanalyses favor multiple sets in causing increases in strength and hypertrophy compared to 1-set (14,15,22,39), while other reviews have criticized the veracity of the metaanalyses concluding there is no difference in strength and hypertrophy increases between single and multiple sets (33, 38). A meta-analysis examining the effect of the number of sets performed has on hypertrophy concluded multiple sets result in significantly greater hypertrophy than single set programs (15). ...
... The ES for all training outcomes investigated supported a dose response effect due to training volume. These findings support meta-analyses and reviews concluding training volume, in the form of multiple sets per exercise or muscle group, shows a dose response pattern with greater increases shown with greater volume (14,15,22,27,39). ...
Full-text available
The study's purpose was to compare the response of performing 1, 3 and 5-sets on measures of performance and muscle hypertrophy. Forty eight men, with no weight training experience, were randomly assigned to one of three training groups, 1-SET, 3-SETS, 5-SETS, or control group (CG). All training groups performed three resistance training sessions per week for six months. The 5RM for all training groups increased in the bench press (BP), front lat pull down (LPD), shoulder press (SP) and leg press (LP) (p≤0.05), with the 5RM increases in the BP and LPD being significantly greater for 5-SETS compared to the other training groups (p ≤ 0.05). BP 20RM in the 3- and 5-SETS groups significantly increased with the increase being significantly greater than the 1-SET group and the 5-SETS group increase being significantly greater than the 3-SETS group (p≤0.05). LP 20RM increased in all training groups (p≤0.05), with the 5-SETS group showing a significantly greater increase than the 1-SET group (p≤0.05). The 3- and 5-SETS groups significantly increased elbow flexor muscle thickness (MT) with the 5-SETS increase being significantly greater than the other two training groups (p≤0.05). The 5-SETS group significantly increased elbow extensor MT with the increase being significantly greater than the other training groups (p≤0.05). All training groups decreased percent body fat, increased fat free mass and vertical jump ability (p≤0.05), with no differences between groups. The results demonstrate a dose response for the number of sets per exercise and a superiority of multiple sets compared to a single set per exercise for strength gains, muscle endurance and upper arm muscle hypertrophy.
Full-text available
Several researchers have recently claimed that a series of meta-analyses unequivocally support the superiority of multiple sets for resistance training, and that they have ended the single versus multiple set debate. However, our critical analysis of these meta-analyses revealed numerous mathematical and statistical errors. In addition, their conclusions are illogical, inconsistent, and have no practical application to resistance training.
Full-text available
This study examined the effects of different volumes of resistance training on muscle size and function over a 10-wk period. Low volume = 3 sets per muscle group per week; moderate = 6 sets; high = 12 sets. Twenty-seven men with 1-4 yrs weight training experience were randomly assigned to the different training volumes and trained 4 days a week. A periodized routine was used; exercises, training intensity, and number of training days were the same for each group. The only variation between conditions was the number of sets per exercise. Pre and post measurements assessed muscular size via ultrasound; strength via maximum squat and bench press; and power via vertical jump and bench press throw. Urinary concentrations of test-osterone and cortisol were also analyzed to assess the responses to training conditions. All 3 training volumes significantly (p < 0.05) increased muscle size, strength, and upper body power, with no significant between-group differences. There were no significant changes in hormonal concentrations. The results support the use of low volume training for muscular development over a 10-wk period. (C) 1997 National Strength and Conditioning Association
Conference Paper
Full-text available
Research has previously been divided on whether performing resistance training with a single set per training session is as effective for increasing strength as training with multiple sets. The purpose of this study was to determine the effect of single sets versus multiple sets on strength. Forty subjects were randomly assigned into 1 of 3 groups: control (C; n = 8), single set (SS; n = 14), or multiple sets (MS; n = 18) to perform 8 maximal knee extensions at 60[degrees][middle dot]s-1 on a Biodex System 3 iso- kinetic dynamometer twice a week for 8 weeks. The SS group performed 1 set while the MS group performed 3 sets. All groups were pre-, mid- (4 weeks), and posttested at 60[degrees][middle dot]s-1. Strength was expressed as peak torque (PT). A 3 x 3 x 2 (time x group x sex) mixed factor repeated measures analysis of variance (ANOVA) revealed no interaction involving sex, but there was an interaction of group by time. The MS group exhibited a significant (p < 0.05) increase in PT (pre = 171.39 +/- 61.98 Nm; mid = 193.08 +/- 66.23 Nm) between the pretest and the midtest while the SS (pre = 163.45 +/- 56.37 Nm; mid = 172.60 +/- 61.78 Nm) and C groups (pre = 135.997 +/- 54.31 Nm; mid = 127.66 +/- 53.12 Nm) did not change. Strength did not change between the midtest and the posttest for any group. It was concluded that performing 3 sets of isokinetic knee extensions was more effective than performing a single set for increasing peak torque. These results seem to indicate that for increasing strength of the quadriceps, performing multiple sets is superior to performing a single set of resistance exercise. (C) 2007 National Strength and Conditioning Association
Purpose: Our goal was to determine the effects resistance training on circulating IGF-I and on two of its major binding proteins, IGFBP-1 and IGFBP-3. Additional goals were to compare the time course of hormonal changes with the time course of strength changes and to determine the effect of training volume on the extent of hormonal changes, Methods: Thirty-one men and women (mean age = 37 +/- 7 yr) completed a 25-wk, 3 d . wk(-1) program in which they performed single-set resistance training (I-SET, N = 11), multiple-set resistance training (3-SET, N = 11), or no exercise (Control, N = 9). Before training, and after 13 and 25 wk of training, blood hormones were analyzed and strength was assessed as the sum of one-repetition maximum (I-RM) far leg extension and chest press exercises. Results: During the first 13 wk of resistance training, circulating IGF-I increased by approximately 20% in both the I-SET and 3-SET groups (P = 0.041). No further increases occurred between 13 and 25 wk. In the 3-SET group, IGFBP-3 decreased 20% between 13 and 25 wk (P = 0.008). Training did not alter IGFBP-1. Increases in 1-RM strength occurred mainly during the first 13 wk of training and were significantly higher with 3-SET training compared to 1-SET. Conclusions: These findings indicate that increased circulating IGF-I may, at least in part, mediate increases in strength that result from resistance training.
ABSTRACT: Purpose: This systematic review of randomized controlled trials (RCTs) comparing strength gains following single-set (SS) and multiple-set (MS) resistance-training protocols was performed to formulate therapeutic exercise recommendations. Methods: Systematic search of Cumulative Nursing and Allied Health Index (CINAHL) and MEDLINE databases for RCTs published between January 1980 and January 2003. Main Outcome Measures: Methodological quality scores based on 10 predetermined criteria, with 100% (10/10) indicating highest quality. Results: Quality scores of the 12 reviewed studies ranged from 50% (moderate quality) to 100% (high quality). Seven studies suggest that MS protocols are superior (MS > SS), and 5 suggest there is no difference in strength gains between SS and MS designs (MS = SS). Mean quality scores were 80.0% (high quality) for the pooled MS > SS studies and 70.0% (high quality) for the pooled MS = SS studies. Conclusions: The higher number of MS > SS studies and slightly higher quality of these pooled studies suggests that MS protocols are more effective for healthy individuals. None of these studies involved patients undergoing rehabilitation; thus, it remains to be seen if the inherently greater time, cost, and presumed injury risk with MS protocols is justified for therapeutic exercise.
Perhaps the most controversial element of any strength training programme is the number of sets required to increase muscular strength and hypertrophy. There is a prevalent belief that at least 3 sets of each exercise are required to elicit optimal increases in strength and hypertrophy. However, most of the studies that reported the results of training with single versus multiple sets do not substantiate this tenet. In fact, the preponderance of evidence suggests that for training durations of 4 to 25 weeks there is no significant difference in the increase in strength or hypertrophy as a result of training with single versus multiple sets. Because of the design limitations of these studies, conclusions concerning the efficacy of multiple sets should be tentative. However, there is little scientific evidence, and no theoretical physiological basis, to suggest that a greater volume of exercise elicits greater increases in strength or hypertrophy. This information may represent an important practical application of time-efficient, low-volume exercise.
The purpose of this series of investigations was to gain insight on resistance training in American football and address some of the myths. Many theories about resistance training have been proposed, yet there has been little if any research on some of these training philosophies. This series of studies represents an accumulation of data that helped to formulate a training approach. Rather than having a training philosophy, it might be more productive to have a training approach based on facts and critical monitoring of test variables representative of the physical development possible through strength and conditioning programs. It was demonstrated that football players are capable of multiple maximal efforts in resistance training and that the length of the rest period was a determining factor. In general, multiple sets and various periodized training programs were superior to single-set programs in the rate and magnitude of improvements in body composition, strength, local muscular endurance, and power. Such data indicate that for building programs in previously trained football players, multiple-set programs that provide variation are more appropriate. (C) 1997 National Strength and Conditioning Association