One set works, three sets works better — 19.8% on bench in eight weeks
In short
In a study where 34 untrained men trained twice weekly for eight weeks across seven exercises of up to ten repetitions, both the single-set and multiple-set groups improved in strength, power and morphology. The multiple-set group gained more: leg cross-sectional area rose 11.3% against roughly 6–8% for single sets, bench press one-rep max rose 19.8% and squat 14.8%, with larger improvements in vertical jump (+6.4%) and Yo-Yo test performance (+3.2%). A volume-dependent dose–response exists even in the earliest phase of training.
"One set is enough when you start" and "do three sets from day one" circulate side by side. This study tested the question directly, randomly assigning 34 untrained men to a single-set group (12), a multiple-set group (11) and a control group (11).
The programme ran eight weeks, twice per week, across seven exercises of up to ten repetitions each. The only difference between the two training groups was sets per exercise — one or three. Assessments covered body composition and limb circumferences, handgrip strength, vertical jump, 20-metre sprint, the Yo-Yo intermittent recovery test, medicine-ball throws, and bench press and squat one-rep maxes.
How large was the difference?
On hypertrophy, the multiple-set group led. Leg muscle cross-sectional area rose 11.3% on both sides, against roughly 6–8% in the single-set group.
Strength followed the same pattern: bench press +19.8% and squat +14.8% favoured multiple sets. Performance measures did too, with vertical jump up 6.4% and Yo-Yo test performance up 3.2%.
So is one set pointless?
No — and this is the part worth holding onto. The single-set group produced moderate but significant gains across most performance outcomes, with leg cross-sectional area rising 6–8%. That came from twice a week, one set per exercise, for eight weeks.
Read together, the conclusion is clear: a volume-dependent dose–response relationship exists in the initial phases of training. More sets buy more, and fewer sets still buy something.
The participants were 34 untrained young men. The results do not transfer directly to trained lifters or other populations — trained individuals generally require more volume than this.
How to use it
- On a genuinely rushed day — one set per exercise clearly beats skipping. Six to eight percent cross-sectional area over eight weeks is not zero.
- As the default — three sets per exercise, which produced larger strength and hypertrophy gains over the same eight weeks.
- Frequency — twice a week, as used here, is a sufficient starting point. Seven exercises at three sets, twice weekly, is a realistic workload.
How this relates to your strength score
This study is unusually useful because it measured two of the three lifts a relative strength score is built on. Gaining 19.8% on bench and 14.8% on squat in eight weeks means a beginner can move their score substantially inside the first two months.
Which is exactly why logging the starting point matters. Beginner-phase gains are steeper than anything that follows, and passing through that phase without a record leaves you with no baseline to compare against later. The calculator needs no account — put your numbers in before the first session. Whether to keep adding volume continues in volume versus intensity.
Frequently asked questions
How many sets should a beginner do?
In an eight-week study of 34 untrained men, three sets per exercise beat one set on cross-sectional area (+11.3% versus 6–8%), bench press (+19.8%) and squat (+14.8%). Single sets still produced significant improvements on most measures.
Does one set per exercise build muscle?
Yes. The single-set group increased leg cross-sectional area by roughly 6–8% and showed moderate but significant gains across most performance outcomes, from twice-weekly training with one set per exercise over eight weeks.
What was the programme in this study?
Eight weeks, twice per week, seven exercises of up to ten repetitions each. The only difference between the training groups was sets per exercise — one versus three.
Do these results apply to trained lifters?
Not directly. The participants were 34 untrained young men, and trained individuals generally require considerably more volume than this to keep progressing.
How fast do numbers rise for a beginner?
In this study bench press one-rep max rose 19.8% and squat 14.8% in eight weeks. Because beginner-phase gains are steeper than any later period, it is worth recording your starting numbers.
Source: PubMed