Do more sets always result in more gains? Is there a point where those gains start to diminish, and adding more sets no longer yields benefits when it comes to optimizing muscle growth and power? Is it worth pushing yourself through those extra sets? Recently, researchers explored the impact of different training volumes, with interesting results. Let’s take a look at the research.
The study
In a study published in the Journal of Applied Physiology, researchers wanted to understand how weekly resistance training volume affects strength, muscle size, and muscular endurance in 55 experienced young adult lifters. How would increasing training volume by 30% or 60% impact muscle changes compared to when the trained lifters continued with their previous training levels?
The study methods
The lifters involved in the study had at least three years of lifting experience and could complete a barbell back squat at least 1.5 times their body weight. The participants were split into three groups:
- A control group that maintained their previous training volume (around 14 weekly sets on average.)
- The group that increased weekly training volume by 30% (approximately 19 weekly sets.)
- The group that increased weekly training volume by 60% (approximately 24 weekly sets.)
For eight weeks, the lifters took part in a lower body training program where they trained twice weekly with back squats, leg presses, and leg extensions. Exercise intensity was adjusted so that the participants were able to keep up with a high level of effort, with around zero to two reps in reserve.
The researchers took measurements prior to and following the training period, including muscle thickness, fat-free mass, back squat one rep max, and strength endurance. Researchers reported the number of reps to failure at 70% of the lifter’s one rep max.
The results
The researchers concluded the following:
- All three groups experienced notable increases in muscle strength and size, but there were no significant differences between the groups regarding muscle growth. All groups increased their fat-free mass and muscle thickness by similar amounts, with an average increase of 7% for muscle thickness and 4.6% for fat-free mass.
- All three groups improved their back squat one rep max, with the control group surprisingly showing the biggest overall increase. Lifters in the control group improved their squat by around 19% or 32 kg. The 30% group increased by around 18 kg, and the 60% group improved their back squat by around 15 kg.
- The 30% group had the most significant enhancement in muscular endurance, increasing reps to failure at 70% of the one-rep max by approximately 26% or 5.5 reps. The control group and the 60% group didn’t experience any notable changes in endurance.
The takeaway
The takeaway is that increasing your sets beyond 12 weekly sets doesn’t necessarily continue to increase your gains. A moderate increase in training volume can improve muscular endurance, as shown in this study, but a larger increase in training volume can cause fatigue that impedes muscle growth.
Increasing your maximal strength doesn’t necessarily require powering through more and more sets. The trained lifters in this study who performed around 12 weekly sets still experienced muscle growth of the quadriceps muscles similar to that of the higher-volume programs, provided that the lifters sustained a high level of effort with zero to two reps left in reserve. This aligns with previous research showing that when you’re increasing training volume, you will likely reach a point of diminishing returns.
