Effect of Number of Sets on Strength Gains in Resistance Training

Key Takeaways

• Multiple Sets Outperform Single Sets: Research shows that performing more than one set per exercise leads to greater strength gains.
• Optimal Range: Around 3–5 sets per exercise per workout tends to maximize strength improvements.
• Training Status Influences Volume: Beginners may start with fewer sets, while trained individuals need higher volumes for continued progress.
• Weekly Volume is Key: Distributing a moderate total number of sets (roughly 10 sets per muscle group per week) is most effective for most.
• Recovery Matters: Spreading sets across multiple sessions helps maintain quality and prevents overtraining.
• Intensity is Crucial: High effort and proper load in each set are essential for strength adaptation.
• It is highly dependant on genetics.

Introduction

Resistance training volume (often measured by the total number of sets performed) is a key factor in strength development. For decades, experts have debated whether performing multiple sets yields greater strength gains than a single set per exercise. The optimal number of sets for maximizing strength is of practical importance for athletes, recreational lifters, older adults, and beginners alike. Recent systematic reviews and meta-analyses provide evidence-based insights into how set volume affects strength gains across different populations. This report summarizes key findings from meta-analytical research (primarily from peer-reviewed sources like PubMed-indexed journals) on set volume and strength, highlighting optimal set ranges, differences between trained vs. untrained individuals (and age groups), and any conflicting evidence.

Single vs. Multiple Sets: What Meta-Analyses Show

Early meta-analyses addressed the classic debate of single-set versus multi-set training:

• Multiple Sets vs One Set: Meta-analyses consistently find that performing multiple sets leads to significantly greater strength gains than doing only one set. For example, a 2010 meta-regression by Krieger analyzed 14 studies and found that 2–3 sets per exercise produced about 46% greater strength gains than a single set​ paulogentil.com. The difference in strength effect size between 1 set and 2–3 sets was statistically significant, whereas additional sets beyond 3 showed diminishing returns (no significant difference between 2–3 sets and 4–6 sets in that analysis)​ paulogentil.com. These results held true in both trained and untrained subjects, supporting the recommendation of multiple sets for maximizing strength.

 

• Short-Term vs Long-Term Training: The advantage of multiple sets becomes more pronounced over longer training durations and in those with training experience. Wolfe et al. (2004) conducted a meta-analysis of 16 studies (ages 15–71, varying training status) and noted that in short programs (6–15 weeks) for novice lifters, a single set can produce strength gains comparable to multiple sets. However, as training progresses beyond the beginner phase or extends in duration, multiple-set programs yield superior strength increases paulogentil.com. In Wolfe’s analysis, trained individuals showed significantly greater strength improvements with multiple sets compared to one set (p < 0.001), and programs longer than 16 weeks also favored multiple sets (p < 0.05)​ paulogentil.com. In practical terms, a newbie might gain strength nearly as well with 1 set in the first few months, but to continue improving and achieve higher strength levels, adding sets is more effective paulogentil.com.

 

• Consistency Across Populations: Notably, the basic pattern of multiple sets being more beneficial is seen across men and women and across young and older adults. An earlier meta-analysis by Rhea et al. (2003) reported similar dose-response curves for strength gain in men and women of all age ranges, with both sexes benefiting from higher training volumes​ researchgate.net. In that analysis, three-set training produced significantly larger strength increases than one-set training (e.g., 3 sets led to ~33% bench press strength gain vs 20% with 1 set)​ researchgate.net. These findings reinforce that the superiority of multiple sets is not limited to a specific gender or age – both young and older adults can generally gain more strength with multiple sets, as long as recovery is managed. (Older individuals may require slightly lower absolute volumes and intensities, as discussed later, but the trend still holds.

In summary, multiple-set training programs are generally more effective for strength development than single-set programs, especially after the initial adaptation period. Even so, performing a minimal number of sets can still induce strength gains – a point explored in research on dose-response and minimal effective doses, detailed below.

Dose-Response Relationship: Optimal Set Ranges for Strength

Research has sought to identify the “dose-response” relationship between training volume (sets) and strength gains – essentially, how strength improvements scale with more sets, and where the point of diminishing returns lies. Key meta-analyses have quantified optimal set ranges for different populations:

• General Strength Training (Mixed Populations): Rhea et al. (2003) conducted one of the first comprehensive dose-response meta-analyses, analyzing 140 studies to determine how intensity, frequency, and volume relate to strength increases. In terms of set volume, they found a clear dose-response up to a point: both untrained and trained individuals achieved maximal strength gains with around 4 sets per muscle group (on average) in a workout​ paulogentil.com. In Rhea’s data, 4 sets per muscle group produced roughly double the strength effect size of a single set, strongly supporting multiple-set training​ paulogentil.com. However, they also observed diminishing returns beyond ~4 sets. For untrained lifters, strength gains tended to drop off when doing more than 4 sets (the effect size actually decreased with 5–6 sets in novices)​ paulogentil.com. For trained lifters, 5 sets yielded about the same or slightly less gains than 4 sets, and there were insufficient data for 6+ sets to draw conclusions​ paulogentil.com. Thus, ~4 sets per muscle group per session emerged as a practical optimum in this meta-analysis, with caution that doing extremely high sets (5, 6 or more in one session) might not provide further benefit and could even be counterproductive for some. It’s worth noting that this analysis defined volume on a per-workout basis; if a muscle is trained multiple times per week, total weekly sets would be higher (e.g. 4 sets × 2 sessions = 8 weekly sets).

 

• Trained vs. Untrained Recommendations: Rhea’s 2003 meta-analysis also offered tailored guidelines by training status​ paulogentil.com. For untrained individuals, the optimal dose was around 60% 1RM intensity, 3 days per week, and 4 sets per muscle group paulogentil.com. For trained individuals, optimal results were seen at 80% 1RM intensity, 2 days per week, and 4 sets per muscle group paulogentil.com. In other words, both groups benefited from ~4 sets, but trained lifters needed higher intensity and slightly fewer frequency, whereas novices thrived on a bit more frequency at lower load. This aligns with the principle that as lifters become more experienced, they require greater intensity (and eventually higher volume spread over time) to continue gaining strength, while beginners can progress with relatively lighter loads but may tolerate a bit more frequency. It’s important to emphasize that the 4-set “sweet spot” was identified for maximizing gains; lower set volumes can still produce strength improvements (just not the absolute maximum), and more than 4 sets might only be useful in special cases or with careful programming to avoid fatigue.

 

• Athletes and High Training Status: A follow-up meta-analysis by Peterson, Rhea, and Alvar in 2004 focused specifically on resistance-trained athletes to see if the dose-response differs at higher training levels. They analyzed 37 studies on competitive athletes and found that to maximize strength, these athletes responded best to a program with ~85% 1RM load, 2 sessions per week per muscle, and about 8 sets per muscle group paulogentil.com. Notably, their trend analysis suggested that strength gains peaked at around 8 sets per muscle group, and gains actually decreased when training volume exceeded 8 sets in those athletes​ paulogentil.com. This led to a recommendation that competitive athletes may need a higher volume (~8 sets per muscle group, presumably per week) to reach peak strength gains​ researchgate.net. However, the authors cautioned that this finding was based on limited data in the very high-volume range. In fact, only a small number of effect sizes in their review represented the 8-set condition, making the evidence for “8 sets is best” less robust​ researchgate.net. As Ralston et al. (2017) later noted, Peterson’s athlete-focused meta-analysis had high variability and some inconsistent patterns at the extreme high volumes​ researchgate.net. Thus, while advanced athletes often tolerate and benefit from higher volume, the exact optimal number (e.g. 8 sets) should be interpreted with caution. It’s likely that well-trained individuals need more volume than novices to keep improving, but there is still a point where piling on additional sets yields diminishing or even negative returns (due to insufficient recovery or reduced training intensity per set).

 

• Weekly Set Volume (Recent Evidence): More recent research examines volume in terms of total weekly sets per muscle. Ralston et al. (2017, Sports Medicine) performed a systematic review and meta-analysis looking at low vs. moderate vs. high weekly set volumes and their impact on strength. They classified training volumes as low weekly sets (LWS) = roughly ≤4 sets per exercise per week, medium (MWS) = ~5–9 sets/week, and high (HWS) = ≥10 sets/week (per exercise). Their findings: moderate and high weekly volumes produced slightly greater strength gains than low volume researchgate.net. In statistical terms, strength increases were marginally but significantly better with MWS or HWS compared to LWS across the studies analyzed​ researchgate.net. For example, when combining multi-joint and isolation exercises, high weekly set training led to greater pre–post strength improvements than low weekly volume (pooled effect size ~0.18 higher)​ researchgate.net. Similarly, doing a medium number of sets (around 5–9 per week) was superior to minimal sets (≤4) for strength (effect size ~0.15 higher) researchgate.net. Importantly, there was not a large difference between moderate and high volumes – the benefit seemed to plateau, as medium vs. high weekly set comparisons were only “marginally” different. Ralston’s key point was that very low volume is suboptimal for strength, while moderate volume is sufficient for most, and very high volumes did not show a huge advantage in the evidence available​ researchgate.net. This aligns with the idea of a dose-response plateau: going from 1 set to ~3 sets clearly boosts strength outcomes, and up to ~5-9 sets per week yields further gains, but beyond ~10 sets per week the incremental gains are smaller. For well-trained males in their analysis, either moderate or high weekly sets were appropriate to maximize strength, whereas for novice/intermediate men, at least a moderate volume was needed to outperform low-volume training​ researchgate.net. In short, a training volume in the moderate-to-high range (roughly 5–10 sets per week per exercise or muscle group) appears most effective for strength, with low-volume programs (e.g. 1–4 sets a week) being less effective. Extremely high volumes (>10 weekly sets per exercise) were not conclusively better than moderate volume, suggesting an upper threshold where other factors (intensity, recovery) become limiting.

Trained vs. Untrained Individuals

Training status significantly influences how volume contributes to strength gains, and meta-analyses have explored this interaction:

• Novice Lifters: As mentioned earlier, beginners can make substantial strength gains with even low training volumes. Initial neural adaptations and learning effects mean that a novice’s first weeks of training yield strength improvements almost regardless of volume (provided intensity and effort are sufficient). Wolfe et al. (2004) found no clear advantage to multiple sets in the first ~6–15 weeks for untrained individuals – one set was nearly as effective as multiple sets in that short term​ paulogentil.com. This suggests that novices can start with minimal sets (1 per exercise) and still get strong initially. However, once this initial period passes, additional sets become important for continued gains. By ~3+ months into training, a single-set routine will plateau, and adding sets provides the progressive overload needed for further strength development​ paulogentil.com. Meta-analyses confirm that beyond the newbie stage, untrained individuals who switch to multiple-set programs outperform those who stay with single sets in strength gains​researchgate.net. In fact, Rhea’s dose-response meta-analysis noted that while beginners have a high potential for improvement, they also exhibit a dose-response to volume: the increase from 1 set to 4 sets in untrained subjects corresponded to a larger effect size gain than the same increase in trained subjects​ paulogentil.com. This finding contradicts the old notion that beginners are “less sensitive” to training volume – on the contrary, novices benefited greatly from the jump to multiple sets (though they will get stronger even on low volume)​ paulogentil.com. The practical takeaway is that a novice can start simple, but to maximize strength gains within their first year, incorporating multiple sets per exercise (at least 2–3 sets) is advisable.

 

• Trained Individuals: People with resistance training experience generally require higher volumes to continue making gains. Their bodies have adapted to the stress of training, so a single set is usually not enough stimulus to elicit further strength increases. The meta-analyses by Rhea and by Wolfe both indicate that trained lifters gain significantly more strength with multi-set training. Wolfe et al. reported that trained subjects doing multiple sets achieved far greater strength increases than any single-set protocol (p < 0.001)​ paulogentil.com. Likewise, Rhea’s analysis showed that trained lifters needed about 4 sets per muscle group to maximize strength, and that doing only one set in trained populations yielded much smaller improvements​ paulogentil.com. Another way to look at it: according to one analysis, trained individuals had to perform ~4 sets to achieve the strength gains that untrained individuals got from just 1 set paulogentil.com. This highlights the principle of diminished returns with training experience – more volume (and intensity) is required to disrupt homeostasis and drive adaptation in a well-trained athlete. Therefore, intermediate and advanced lifters are generally recommended to perform multiple sets (often several sets per exercise, and multiple exercises per muscle group weekly) to keep gaining strength. For example, instead of one all-out set, a trained lifter might use 3–5 work sets on a major lift to provide sufficient stimulus. As training status advances further (into competitive athletic levels), volume demands may increase, but as noted earlier, there is likely a cap where excessive sets don’t yield proportional benefits.

 

• Similar Gains for Trained vs. Untrained (with Volume): Interestingly, when both untrained and trained individuals use multiple-set programs, their relative strength gains can be similar. Wolfe’s meta-analysis noted that untrained individuals performing multiple sets achieved strength gains comparable to trained individuals using multiple sets​ researchgate.net. In other words, given an appropriate volume, beginners can improve at a rapid rate (often faster in absolute terms due to low starting strength), and trained lifters continue to improve albeit at a slower percentage rate. The key is that both groups benefit from higher volumes, but the trained group simply cannot progress with very low volume the way a beginner briefly can​ researchgate.net. For coaches and practitioners, this means training status should guide volume prescriptions: start novices with low-to-moderate sets and ramp up volume as they adapt, whereas experienced lifters should typically train with moderate-to-high volume to see appreciable strength gains.

Age Considerations: Younger vs. Older Trainees

Age is another factor often considered in training programming. Do older adults respond differently to training volume than younger adults? Research suggests that the fundamental response is similar, though older individuals might need to moderate total volume slightly due to recovery considerations:

• Older Adults: Meta-analyses focusing on resistance training in older populations (e.g., age 50–70+) indicate that multiple-set training is still superior for maximizing strength in older adults, much like in young adults. For instance, Peterson et al. (2010) conducted a meta-analysis on resistance training in older adults and found that higher-volume programs led to greater strength improvements than low-volume ones, up to the point that participants could recover and tolerate the training. A recent systematic review noted that low-volume training (e.g. single-set routines) can produce meaningful strength gains in older adults, but higher volumes are necessary for greater improvements in strength europepmc.org. In practice, older trainees often start with 1–2 sets per exercise and still gain strength (especially if untrained), but to maximize strength outcomes (e.g., for improving functional strength or more ambitious goals), progressing to multiple sets is beneficial europepmc.org. One caveat is that older individuals may have reduced recovery capacity and a higher risk of overuse injuries, so the optimal volume for an older adult might be on the lower end of the effective range. Consistent with this, reviews have observed that the training “dose” that works best for older adults is broadly similar to younger adults except with slightly lower volume and intensity on average strongerbyscience.com. In simpler terms, seniors benefit from the same approach of gradually increasing sets to boost strength, but the peak effective volume for an older lifter might be a bit less than that for a young lifter who can handle more sets. For example, an older adult might find ~2–3 sets per exercise (total ~6–9 sets per muscle per week) yields excellent strength gains, whereas a younger athlete might push to 4–5 sets (10+ sets/week) for maximal development, given adequate recovery.

 

• Younger Adults: Young and middle-aged adults generally recover faster and can handle higher training volumes. Meta-analyses haven’t identified any unique volume response in younger people that differs from the general population trends – they follow the same dose-response of low-to-moderate sets being good, and moderate-to-high being better up to a point. As noted earlier, Rhea’s meta-analysis found no difference in volume response across age ranges (the dose-response curves were comparable for all ages studied)​ researchgate.net. Thus, a healthy adult in their 20s or 30s should plan their training volume primarily according to training status and goals, rather than age per se. It’s only at more advanced ages (senior populations) where some volume adjustments might be warranted.

In summary, older adults can and do gain strength with multiple-set training, and their optimal set range is not fundamentally different from that of younger adults, though it may be wise to err on the lower end of volume at first and increase sets more conservatively to account for recovery limitations. The overarching principle – that doing more sets (within reason) yields more strength – applies regardless of age, as long as the individual can recover from the training.

Training Frequency and Volume Interaction

Training frequency (how many days per week a muscle or exercise is trained) can influence how volume is accumulated. It’s important to note that total volume (sets) and frequency are interrelated – e.g., 10 sets per week could be done in one mega-session or spread over 2–3 sessions. Meta-analyses have examined whether frequency itself affects strength gains when volume is accounted for:

• Frequency with Equal Volume: When total weekly set volume is matched, increasing frequency (splitting the sets into more sessions) does not seem to markedly improve strength gains. Recent evidence indicates that total sets per week is the primary driver of strength improvement, rather than how those sets are distributed across the week​ barbend.com. For example, performing 6 sets for a muscle in one session versus 3 sets in two sessions (3 sets twice a week) yields similar strength outcomes if effort and intensity are equivalent, according to several systematic reviews. A 2019 meta-analysis by Schoenfeld and colleagues on training frequency reported no significant difference in strength gains between training a muscle group 1×, 2×, or 3× per week when volume was held constant – all groups made similar 1RM improvements given the same total sets and intensity. What this means is that frequency can be viewed as a tool to distribute volume for recovery convenience, rather than an independent stimulus for strength (beyond the first day per week). In fact, one analysis found the major jump in gains was from not training to training a muscle once per week (obviously), and going from one to two sessions per week gave a smaller additional benefit, while beyond two sessions the returns were minimal if volume was equal​ barbend.com.

 

• High Frequency via Volume Increase: Many programs for strength (especially in powerlifting contexts) employ high frequencies (e.g., training a lift 3-4 times weekly). These can be effective because they allow more total sets and practice of the lift. However, the meta-analyses suggest that it’s the increase in volume that drives the extra gains, not the frequency per se. If one group trains bench press 3×/week and another 1×/week, and the 3× group gains more strength, it’s usually because they did more sets and total work, not simply because of frequency. When researchers ensure both groups do, say, 9 sets/week (either 3 sets ×3 days or 9 sets ×1 day), strength outcomes tend to be comparable – provided fatigue in the one-day protocol is managed.

 

• Practical Frequency Guidelines: While frequency alone might not boost strength, it is crucial for managing volume. Doing too many sets in one session can lead to excessive fatigue, reduced per-set quality, or recovery issues. Spreading volume across the week allows higher quality work. For instance, if someone’s optimal weekly volume is 12 sets for a muscle, it would be wise to split that into at least 2 or 3 days (e.g., 4 sets ×3 days) rather than all 12 sets in one marathon workout. Research supports this practical approach: one analysis categorized studies by “recoverable volume” per session and noted that when volume per session was extremely high, higher-frequency routines suffered (likely due to overtraining in each session)​ barbend.com. But when volumes per session were kept moderate, frequency made little difference​. The bottom line is choose a frequency that allows you to perform the target number of sets with good form and adequate recovery. For most, this means training each muscle ~2–3 times per week with moderate per-session volume, which aligns with typical strength training recommendations (e.g., an upper/lower split or full-body routine repeated 2–3× weekly). Very high frequencies (4–6×/week per muscle) can work if volume per session is very low, but that’s uncommon outside of specialized programs. In summary, training frequency should be set such that weekly volume can be achieved without excessive fatigue in any given workout; total set volume is the key factor for strength gain, and frequency is a means to distribute that volume effectively.

Summary of Optimal Set Ranges for Strength Development

Taking the evidence together, we can outline some practical ranges for set volume that have been supported by research. (These ranges assume sets are performed with a challenging load/intensity, e.g. near 6–12 repetition maximum effort, as most studies use.)

• Beginners (Untrained Individuals): Start low and progress. Even 1 set per exercise can induce strength gains in the first weeks of training for novices​paulogentil.com. However, to maximize gains over a training program, beginners should progress to 2–3 sets per exercise for major muscle groups paulogentil.com. Meta-analyses suggest 2–3 sets yield significantly better strength outcomes than single sets in both untrained and trained people​paulogentil.com. A reasonable guideline for novices is ~4–8 total sets per muscle group per week (e.g. 2 sets per session, twice a week for each muscle) as a starting volume, increasing toward the upper end as they become comfortable. This aligns with Rhea’s finding of 4 sets ×3 days/week being optimal for novices to fully tap their potential​ paulogentil.com, though that is a rather high frequency. In practice, a novice might do 2–3 sets per exercise in a full-body routine 2–3 times a week, hitting ~6–9 sets per muscle weekly.

 

• Intermediate Lifters: Once past the beginner stage (after a few months of training), lifters generally respond best to moderate volume. Research points to roughly 3–5 sets per exercise as an optimal range for intermediates, translating to around 10–15 sets per muscle group per week if that muscle is trained 2–3 times weekly. For example, an intermediate might do 3 sets of bench press and 2–3 sets of an accessory press, twice per week, totaling ~10–12 sets for chest weekly. This falls in the “medium” volume category (5–9 sets per exercise per week) which Ralston et al. (2017) found to produce superior strength gains over low volume​researchgate.net. It’s also consistent with the plateau observed around 4 sets per session in Rhea’s dose-response meta​ paulogentil.com – doing 4 hard sets in a workout for a muscle is near optimal, and doing that twice a week gives 8 sets weekly (or three times/week gives 12 sets), which is a solid volume for strength gains. Intermediates can experiment within this range; if progress stalls, a bump from, say, 8 to 12 sets per week (adding an extra set or an extra exercise) can spur new gains, as long as intensity is maintained.

 

• Advanced Lifters & Athletes: Advanced strength athletes (powerlifters, weightlifters, etc., with multiple years of training) often require higher volumes to eke out further strength gains, but they must balance this with recovery and intensity. Meta-analytic evidence (Peterson et al. 2004) indicates that experienced athletes achieved peak strength gains with around 8 sets per muscle group per week (when training each muscle 2 times weekly at high intensity)​paulogentil.com. Some advanced programs go even higher (e.g., 10–12 sets or more per muscle per week), but the returns diminish and individual tolerance varies. A recent systematic review (Ralston 2017) supports using high volume (≥10 sets/week) for advanced trainees, as it showed high volumes produced slightly greater strength effects than moderate in trained men​ researchgate.net. Practically, advanced lifters might use 4–6 sets per session for a big lift, 1–3 times per week, totaling anywhere from ~8 up to ~18 sets weekly for that movement or muscle. For example, an advanced squatter might do 5 sets of squats on Monday and 3–4 sets on Thursday, totaling ~8–9 weekly sets, and add some supplemental work (which adds a few more sets for quads) – landing around 10–12 sets for quads weekly. This is within the range many coaches recommend (often 8–15 sets/week for large muscle groups for strength/hypertrophy maintenance, and up to ~20 for specialization phases). It’s important that advanced athletes periodize their volume and have deloads, as consistently doing the upper end of volume can lead to fatigue. Additionally, extremely high volumes (e.g., 20+ sets per week) may necessitate submaximal loading and could shift focus more toward hypertrophy than maximal strength. Optimal strength gains for advanced lifters typically come from a high-but-manageable volume paired with high intensity – for instance, doing multiple heavy sets across the week rather than one marathon session.

 

• Older Adults: For older trainees (50+ years), the optimal set range tends to be slightly lower, but not drastically different from younger adults. Research suggests older adults can improve strength with low volume (1–2 sets), but for robust gains, 2–3+ sets per exercise are beneficial​ europepmc.org. A sensible target might be ~6–10 sets per muscle per week for older lifters, depending on individual recovery. For example, an older adult might do 2 sets per exercise and train each muscle twice weekly (≈8 sets/week total). This moderate volume has been shown to significantly enhance strength while minimizing risk of overuse. As always, individual differences matter – some older individuals can handle higher volumes similar to young people, especially if they’ve been training for years, whereas others progress better with minimal volume. Monitoring recovery and progress is key. In summary, older adults should not fear multiple sets – they generally should incorporate them for best results, adjusting the total number of sets to what they can recover from (often a bit less than a younger person with similar training status).

These ranges are guidelines informed by averages from studies. The optimal volume for any individual might vary. One should adjust sets based on how one feels and progresses – if strength gains stall and fatigue is low, adding a set or two might help; if one is very fatigued or not recovering, it may indicate too many sets are being done for the current capacity.

Conflicting Evidence and Considerations

While the overall evidence favors multiple sets for maximizing strength, there have been some conflicting findings and nuances to consider:

• Minimal Effective Volume: An emerging area of research looks at the minimum volume needed to make gains, which can seem to conflict with “more is better.” A 2020 systematic review by Androulakis-Korakakis et al. examined trained lifters and found that surprisingly low volumes can still yield strength increases. Specifically, as little as one hard set per exercise, performed 2–3 times per week (i.e. ~2–3 total sets per week per lift), was sufficient for intermediate lifters to continue making modest strength gains in major lifts​  strongerbyscience.com. This doesn’t contradict the fact that higher volumes produce greater gains – rather, it highlights that you don’t need enormous volumes to improve. Even at low volume, if intensity and effort are high (e.g. one set to failure at ~80% 1RM), strength can increase, just not as much as with higher volumes. These findings are encouraging for individuals who prefer shorter workouts or during periods when maximizing efficiency is more important than maximizing absolute gains. It shows a clear spectrum: to maximize strength, higher volumes help, but to achieve, say, ~70–80% of one’s potential gains, relatively low volume can suffice strongerbyscience.com. This nuance is important because it reminds us that optimal volume depends on one’s goals and constraints – not everyone needs to do 5 sets of every exercise if their goal is general strength and health.

 

• One-Set Advocates: In the past, some researchers argued that one set per exercise is “enough” for strength, citing that many studies did not show statistically significant differences between 1 vs 3 sets. This led to a debate in the early 2000s (with authors like Carpinelli and colleagues often advocating single-set training). However, the weight of evidence from meta-analyses now indicates a clear advantage (albeit sometimes a modest one) to multiple sets paulogentil.com. The lack of significance in some individual studies was likely due to small sample sizes or untrained subjects (who, as noted, can gain strength rapidly even on low volume in the short term). When data are pooled across studies, the trend leans in favor of multiple sets. That said, the magnitude of the advantage can vary. For example, Krieger’s 2010 analysis found a difference in effect size of 0.25 (which is a small-to-moderate effect) favoring 2–3 sets over 1 paulogentil.com. This means multiple sets accelerated strength gains, but not by an astronomically large degree in every case. In practical terms, a program of 3 sets might make you, say, 10% stronger after 8 weeks, whereas 1 set might have made you 7% stronger – a meaningful difference for athletes, but a casual lifter might or might not care. This context sometimes fuels debate on whether the extra time doing sets is “worth it” for everyone. Individuals focused on maximal strength will generally find it worth the effort to do multiple sets, whereas someone prioritizing time efficiency may accept slightly smaller gains for a big cut in workout duration (see “minimum effective dose” above).

 

• Inter-individual Variation: Not all lifters respond identically to volume. Some people are “high responders” to volume, gaining substantially more when training with more sets, while others are “low responders” who may see little added benefit or even regress if volume is too high. Meta-analyses report averages, but within those data are individuals who thrived on one set and others who needed five sets. Coaches often adjust volume based on an athlete’s observed response. Signs that you’ve exceeded your optimal volume include stalled strength gains, excessive fatigue, or reduced performance on later sets. Conversely, if you finish workouts feeling you could do more and you’re not progressing, it might be a sign to add a set. The principle of individualization means the optimal set number might be at the low end for some and high end for others, even among those with similar training status.

 

• Quality of Sets vs. Quantity: It’s also worth noting that the quality (effort, intensity, technique) of each set matters tremendously for strength gains. Doing more sets with sub-maximal effort or poor form may not beat fewer, high-quality sets. Many of the studies included in these meta-analyses ensured sets were taken close to muscular failure or at a high intensity (e.g., percentage of 1RM). If someone does multiple sets but stops far from failure each time, they might see less adaptation than someone who does fewer sets but pushes them harder. Therefore, volume should be considered in context with intensity. Training volume and intensity have to be balanced. Some conflicting findings about volume could be due to differences in intensity: for example, a high-volume group that used a lower intensity might not gain more strength than a lower-volume, higher-intensity group. In practice, to maximize strength, one should use both sufficient intensity (generally >70% 1RM for most sets) and sufficient volume (multiple sets). Extremely high volumes could force one to use lighter weights or insufficient recovery, which might impair strength-specific adaptations.

 

• Overtraining and Recovery: A final consideration is the risk of overtraining or overuse with very high set numbers. A few meta-analyses and reviews, such as Ralston et al. (2017), point out that more is not always better indefinitely researchgate.net. The difference between moderate and high volumes was “marginal” in Ralston’s review, hinting that doing extra sets past a certain point yields little extra benefit and could potentially hamper recovery. Indeed, some studies have documented instances where cutting back volume led to improved strength due to better recovery (particularly in overreached athletes). The key is to find the minimum effective volume that still maximizes gains for you – beyond that, additional sets just eat into recovery capacity. This will differ based on factors like nutrition, sleep, age, and genetic recovery ability. Periodization models often cycle volume, with phases of higher volume to build work capacity or hypertrophy, and phases of lower volume but higher intensity to peak strength. Using phases helps avoid chronic overtraining at high volumes.

Conclusion

Multiple lines of evidence from systematic reviews and meta-analyses converge on the conclusion that training with multiple sets per exercise is superior for strength development compared to single-set training, especially after the initial learning phase. Optimal strength gains generally follow a dose-response curve with volume: going from 1 set to ~3–5 sets markedly enhances gains, and moderate-to-high weekly set volumes (about 5–10 sets per muscle group per week or more) are associated with greater 1RM improvements than very low volumes​ researchgate.net paulogentil.com. However, this relationship plateaus and may reach a point of diminishing returns – extremely high volumes (>10–15 sets/week for a given exercise) do not always yield proportionally greater strength and can impede recovery​ paulogentil.com. The precise “optimal” number of sets depends on training status and individual differences.

For novice lifters, research (as of 2003–2004) suggests they can gain strength well with just a few sets, but to maximize gains even novices benefit from doing 2–3 sets per exercise​ paulogentil.com. For intermediate and advanced lifters, recent evidence (2010s) indicates that a more substantial volume is needed – typically 3+ sets per exercise, or on the order of 8–12 sets per muscle per week, to continue making progress​paulogentil.com. Competitive athletes may push toward the higher end (~8+ sets per muscle weekly) for maximal strength, though with careful programming​ researchgate.net. Older adults show similar trends, albeit often utilizing slightly fewer sets (moderate volume) to allow recovery​ strongerbyscience.com. Across the board, men and women respond similarly to set volume when other factors are equated​ researchgate.net.

It should be noted that quality matters: performing sets to a sufficient intensity (and not just “going through the motions” of more sets) is crucial for strength adaptation. Also, training frequency should be configured to support the volume – spreading sets across multiple sessions can help maintain intensity and reduce fatigue per workout, which is beneficial for strength gains. The consensus of recent meta-analyses is that total weekly volume is a primary driver of strength gain, with frequency being secondary (i.e. how you split that volume up)​ barbend.com.

Finally, while the research provides general guidelines, there is some conflicting evidence and ongoing refinement of what is truly “optimal.” The differences in strength gains between, say, 2 vs 3 sets or 6 vs 8 sets are not always enormous, and individual response can vary. Some lifters might progress well on lower volumes (especially if they train very hard), whereas others thrive on higher volume routines. The current body of evidence (as of 2023) suggests an optimal range rather than a single number of sets – most people will gain best somewhere in that moderate-to-high volume zone, and finding the lower end of that zone that still gives near-maximal gains is a wise approach for efficiency. As new research emerges (e.g., exploring very high-level lifters or different periodization of volume), our understanding of volume’s role continues to be refined, but the foundational principle remains: to get stronger, you need to do enough work (sets) to challenge your muscles, and doing more than one set per exercise provides a clear benefit in the long run. Balancing volume with intensity and recovery will ensure the best strength outcomes.

Sources:

• Krieger JW. J Strength Cond Res. 2010;23(6):1890-1901 – meta-analysis showing 2–3 sets produce ~46% greater strength gains than 1 set​
• Wolfe BL et al. J Strength Cond Res. 2004;18(1):35-47 – meta-analysis finding multiple sets superior in trained lifters and over longer programs, while single-set is comparable only in short-term novice training​.
• Rhea MR et al. Med Sci Sports Exerc. 2003;35(3):456-464 – dose-response meta-analysis identifying ~4 sets as optimal per session for max strength gains (both untrained and trained), with diminishing returns beyond 4​.
• Peterson MD et al. J Strength Cond Res. 2004;18(2):377-382 – meta-analysis on athletes recommending ~8 sets per muscle group (weekly) for maximal strength, though data at that volume were limited​
• Ralston GW et al. Sports Medicine. 2017;47(12):2585-2601 – systematic review/meta finding moderate (5–9 sets/week) and high (≥10 sets/week) volumes yield slightly greater strength gains than low volumes (≤4 sets/week), especially in well-trained individuals​.
  
• Androulakis-Korakakis P et al. Sports Medicine. 2021 (published online 2020) – systematic review on minimum effective training dose indicating even 1 set to failure, 2–3×/week can increase 1RM in trained men (though not maximal gains)​