The data comes from a new review of 67 studies published as a preprint on SportRxiv — an open-access platform where researchers share their work before peer review, Health reports. The analysis identifies which training practices most effectively support muscle mass and strength development.

The conclusion: increasing the number of sets during resistance training is beneficial, but only up to a point. “The quality and intensity of effort matter more than the quantity,” said Dr. Jeremy Swisher of UCLA’s Sports Medicine Fellowship Program in an interview with Health.

How Many Sets Per Workout Are Necessary?

Although there is plenty of research on training frequency and volume, few studies have addressed how workouts should be structured, explained lead author Jacob Remmert, a PhD candidate at Florida Atlantic University.

To answer that question, Remmert and his team analyzed data from over 2,000 participants. In the study, they defined two types of sets:

Direct sets – exercises that target a specific muscle group as the primary mover (e.g., a bench press for the chest).

Fractional sets – exercises where a muscle is involved but not as the main driver (e.g., triceps extensions, which indirectly activate the chest). These count as half a set.

The results showed that both strength and muscle mass improved with more sets — but:

Muscle growth plateaued after about 11 fractional sets per session.

Strength gains plateaued after about 2 direct sets per session.

“The first few sets in any workout yield the greatest return on investment,” summarized Remmert.

How to Build an Effective Strength Training Plan

To increase strength, it's advisable to follow a higher training frequency — about two to three times per week — with a relatively low number of sets per session. The same approach can work for muscle growth, or alternatively, fewer training days per week with more sets per session.

Even moderate but consistent strength training can significantly benefit health, added Jordan Boreman, an exercise physiologist at Cleveland Clinic.

Limitations of the Study

It’s important to note that the study is not peer-reviewed, so the results are preliminary. Furthermore, it encompassed a broad range of training protocols, which may affect the precision of its conclusions. The participants were predominantly young and healthy, and the analysis focused on short-term results.

Future research should include more diverse demographics, investigate long-term effects, and explore how recovery and injury risk factor into different training strategies.

Why Fewer Sets May Lead to More Strength

While it may seem counterintuitive, fewer sets with heavier weights have consistently been shown to improve strength. According to Dr. Swisher, intense early sets help recruit the maximum number of muscle fibers and trigger most strength-building mechanisms. Additional sets bring diminishing returns while significantly increasing fatigue and recovery time.

Boreman warns that excessive volume may cause chronic fatigue and a drop in performance, particularly when training for strength.

How to Apply the Findings in Practice

The study can serve as a guideline — especially for beginners starting to build a strength routine. Remmert recommends beginning with fewer sets and increasing volume as progress stalls.

The ideal number of repetitions per set depends on your goal:

• 1–5 reps for strength and power
• 6–12 reps for muscle growth
• 13–20 reps for endurance

Ultimately, workouts should be tailored to individual needs. Keeping a log to track sets, reps, and weight can help monitor progress and make informed adjustments to your program, Swisher concluded. |BGNES