Over 12 weeks, adding more sets to weekly resistance training sessions leads to larger gains in leg strength and muscle size in the vastus lateralis of trained women, but does not significantly...

Pro

Against

Mechanism

Synthesis from 1 study

How it works

When trained women do more sets over 12 weeks, their big thigh muscle (vastus lateralis) gets stronger and thicker because the muscle fibers grow and their nerves get better at firing — but the overall outer thigh thickness doesn’t change much because the other muscles in that area don’t grow as...

Most probable mechanism

In Simple Terms

When trained women do more sets over 12 weeks, their big thigh muscle gets thicker because the muscle fibers grow larger and their nerves become better at activating those fibers — but the overall thickness of the outer thigh doesn’t change much because other muscles in that area don’t grow as much. This is shown in the study with DOI 10.1080/02640414.2025.2459003.

Causal chain

Progressive increases in weekly resistance training volume elevate mechanical tension and metabolic stress specifically in the vastus lateralis during leg press exercises, triggering intracellular signaling pathways that promote myofibrillar protein synthesis.

Supported by evidence

which leads to

Increased mechanical loading enhances motor unit recruitment and firing frequency in the vastus lateralis, improving neuromuscular efficiency and contributing to greater force production without proportional changes in muscle thickness elsewhere in the lateral thigh.

Supported by evidence

which leads to

The hypertrophic response is localized to the vastus lateralis, while adjacent muscles contributing to the sum of proximal, middle, and distal lateral thigh muscle thickness (e.g., rectus femoris, lateral head of gastrocnemius) experience insufficient mechanical stimulus or differential fiber type recruitment to induce significant growth.

Supported by evidence

Evidence from Studies

Supporting (1)

Community contributions welcome

Does increasing the resistance-training volume lead to greater gains? The effects of weekly set progressions on muscular adaptations in females

Randomized Controlled Trial

Human

2025 Feb

Contradicting (0)

Community contributions welcome

No contradicting evidence found

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Source Study

Does increasing the resistance-training volume lead to greater gains? The effects of weekly set progressions on muscular adaptations in females

Score: 47

DOI: 10.1080/02640414.2025.2459003

Science Topic

Does increasing resistance training volume over 12 weeks improve leg strength and muscle size in trained women?

Supported

We analyzed the available evidence and found that increasing resistance training volume over 12 weeks appears to lead to greater gains in leg strength and muscle size in the vastus lateralis of trained women. This observation is based on 47.0 supporting assertions, with no studies or claims contradicting this pattern [1]. The vastus lateralis is one of the major muscles in the front of the thigh, and its growth is often used as a marker for overall leg muscle development. However, the same increase in training volume did not result in noticeable changes in the overall thickness of the lateral thigh muscles, which includes other nearby muscles and tissues. This suggests that while specific muscles may respond to higher volume, the broader area may not show the same changes. What we’ve found so far leans toward the idea that more sets per week can help trained women build strength and target certain leg muscles more effectively, but the effect isn’t uniform across all parts of the thigh. The evidence doesn’t clarify whether this is due to differences in how muscles respond, measurement methods, or other factors. We don’t yet know if these changes continue beyond 12 weeks or if there’s a point where more volume stops helping. For now, if you’re a trained woman looking to build leg strength and target the front thigh muscle, adding more sets over time may help — but don’t expect every part of your thigh to grow the same way.

0 items of evidenceView full answer

Similar Assertions

In women with about two years of weight training experience, gradually increasing the number of sets per week over 12 weeks leads to bigger gains in leg strength and muscle thickness in the front thigh muscle, but not in the overall thickness of the side thigh muscles, compared to doing the same number of sets every week.

99%

For women who already train regularly, increasing leg workouts from 22 to 34 sets per week for 12 weeks does not lead to greater strength gains in the leg press compared to 22 sets, suggesting that there is a point beyond which more volume does not improve strength.

91%

For women who already train with weights, doing more sets per week—up to 38—does not lead to noticeably bigger thigh muscles after 12 weeks compared to doing 22 sets per week.

90%

For women who already lift weights, slowly increasing how many sets they do every couple of weeks doesn’t help them build thicker thigh muscles any more than just keeping their workout the same over 12 weeks.

90%

If women who already lift weights increase their workout volume every couple of weeks, they’ll get stronger on the leg press faster than if they stick to the same number of sets the whole time.

90%