Resistance training for strength and muscle gains: is less more?

Hard training is clearly a necessary component of getting better at sport. Many athletes have experienced how working harder to leads to faster improvements and larger improvements. It’s only natural to conclude therefore that this is a linear process where more is better. In recent years however, more and more research has emerged indicating there is an optimal amount of volume and intensity that leads to the largest improvements, rather than a maximal amount of volume and intensity.

Maximum performance, minimum time

Most athletes want to maximize performance, but no one wants to waste time, and no athlete wants to spend precious time and energy without a return on their investment. Over the years, strength training has become a critical component of training process, and athletes and coaches must intelligently integrate strength training into a holistic training program. If there’s an optimal amount of total work that can be done, performing more strength training typically requires a reduction in the amount of work performed in other areas, including endurance training and sport-specific work. As a result, there’s a lot of confusion as to how much strength training should be performed, and whether increases in training volume will lead to increases in muscle mass and strength. When athletes want to gain more muscle or strength, they often default to increasing the volume. But is this the best strategy? Fortunately, a group of international researchers have sought to provide clarity to this very question.

New research

The purpose of this new study was to investigate the impact of increases in training volume on improvements in muscle mass and muscular strength⁽¹⁾. Twenty nine subjects took part in the study. Importantly, these were well-trained individuals. They were all males between the ages of 18-40, and they had all been training for at least three years. Not only had they been training, but they’d also been training with at least some level of intensity as they were required to be able to squat 1.5 times bodyweight to participate.

The subjects were divided into three groups. While all three groups performed the same training program, each group performed a different number of sets. The first group simply maintained the number of sets that they had been performing for their lower body prior to beginning the study. The second group performed 30% more sets than they had previously, and the third group performed 60% more sets than they had been performing previously. It’s important to note that the subjects were performing a wide number of sets because that number was based upon their previous training. The subjects trained twice per week for eight weeks using the squat, leg press, and leg extension exercises.

The subjects were tested for changes in muscle mass and muscular strength of the legs. To measure fat free mass, DEXA scans were performed. DEXA is an x-ray technology that is the gold standard for measuring the amount of tissue in the body, whether fat mass, fat free mass, or bone. This accurate technology was used to determine whether there changes in fat free mass of the thigh over the course of the intervention. Ultrasound was also used to determine the thickness of the thigh musculature. Measurements were taken at the proximal thigh, which is closest to the hip, and the distal thigh, which is closest to the knee.  This provided another perspective on the amount of muscle that was gained during the training.

Two ‘before and after’ strength assessments were performed to determine the performance impact of changes in set volume:

• The participants each performed a one repetition squat test. The goal was to lift the heaviest weight they good during a barbell squat while achieving a knee flexion angle of 100 degrees. The lifters had to achieve this depth for the repetition to count.
• The participants also performed a squat test to exhaustion with 70% of the weight they lifted during the maximum strength test. For each repetition, the subjects were required to achieve a knee flexion angle of 100 degrees.

 What they found

Unsurprisingly, the training program was effective at improving measures of muscle mass and muscle strength regardless of the program used. All three groups increased all measures of muscle mass, and all groups improved during the strength tests. More surprising however was that the differences between the groups in terms of the magnitude of the improvements were minimal – in fact, there were no statistically significant difference between the groups in any of the measurements of muscle mass (see figure 1)! And while the numbers were almost identical, they slightly favored the control group that did not increase training volume.

From a muscle mass perspective, the extra work was simply a waste of time! In terms of performance, maximal strength gains were significantly better in the control group. This means that when the goal is to optimize strength improvements, lower strength training volumes may be beneficial. During the repetition to failure test, the group performing an additional 30% more sets demonstrated a significantly larger improvement. Based upon the limited amount of research in this area, the researchers were not able to provide a plausible explanation as to why this may be the case.

Figure 1: Changes in muscle thickness and fat-free (lean) mass