The Core Idea: Training Volume
At its heart, strength training success hinges on a principle called 'progressive overload'—gradually asking your muscles to do more work. The most common way we measure this work is through 'training volume'. Think of it as the total workload for a muscle,
typically calculated as sets multiplied by reps multiplied by weight. While reps and weight are crucial, the number of 'hard sets' you perform per muscle group each week is widely considered a primary driver of muscle growth, or hypertrophy. For years, the simple advice was to just do more. But as anyone who has felt overtrained knows, there's a limit.
More Isn't Always Better: Diminishing Returns
The relationship between training volume and muscle growth follows the law of diminishing returns. The first few sets you do for a muscle provide a powerful growth signal. As you add more sets, the benefit you get from each additional one starts to shrink. Eventually, you reach a point where adding more sets provides almost no extra benefit but generates a lot of fatigue. This extra, non-productive work is often called 'junk volume'. It doesn’t just waste your time; it can actively hinder your progress by impairing recovery, increasing injury risk, and impacting your ability to train hard in your next session.
What the Latest Science Says
So, where is that sweet spot? Recent meta-analyses—which combine data from multiple studies to draw stronger conclusions—have refined our understanding. A growing body of evidence confirms a dose-response relationship: more volume generally leads to more growth, but only up to a point. Most research now points to a range of 10-20 hard sets per muscle group, per week, as the optimal range for most trained individuals. While beginners can see significant gains with fewer sets, and elite athletes may sometimes benefit from more, that 10-20 set window seems to be the sweet spot for maximising growth without accumulating excessive fatigue. Some studies show that going beyond 20 weekly sets results in very little, if any, additional muscle growth for most people.
Focus on Weekly Totals, Not Single Workouts
A crucial mistake is trying to cram all that volume into a single, marathon session. Evidence suggests there’s a limit to how much productive volume you can do in one workout, often estimated around 6-10 hard sets per muscle. Beyond that, fatigue compromises your form and intensity, turning effective sets into junk volume. The smarter approach is to spread your weekly volume across two or three sessions. For example, if your goal is 16 sets for your back, performing 8 sets on Monday and 8 more on Thursday is almost always more effective than grinding through 16 sets in one day. This approach allows for higher quality work in each session and better recovery.
Finding Your Personal Sweet Spot
The 10-20 set range is a guideline, not a rigid rule. Your ideal volume depends on several personal factors. Training experience is key; the longer you've been lifting, the more volume you'll likely need to keep progressing. Your genetics, age, nutrition, sleep quality, and life stress also play a huge role in your ability to recover from and adapt to training. The best strategy is to start at the lower end of the recommended range (around 10-12 sets per week) and track your progress. If you are consistently getting stronger and recovering well, you're likely in a good place. Only consider adding more sets if your progress stalls for several weeks and you feel your recovery is excellent.
