How to Build Bigger Legs

How do you build bigger legs? Squat to a real depth, since research consistently shows quad growth responds to depth, not just weight on the bar. Add a hip hinge movement like Romanian deadlifts for the hamstrings, which squats train only lightly. Include single-leg work like Bulgarian split squats to catch strength imbalances a barbell exercise can hide, and hit enough weekly volume across quads and hamstrings both. Keep adding weight or reps over time, and the size follows.

Here's what the research says about squat depth, why hamstrings need their own movement, and how to put a leg routine together that grows both.

Does squat depth really change how much your quads grow?

The evidence points that way. A study by Bloomquist and colleagues compared a shallow squat, stopping around 60 degrees of knee flexion, to a deeper squat going to about 120 degrees, and found greater quad cross-sectional area growth in the deeper group, particularly toward the lower part of the thigh. Separate work by Kubo and colleagues compared a 90-degree squat to a 140-degree squat and found quad growth was similar between the two, though the deeper squat produced more growth in the glutes and adductors. Taken together, the research doesn't point to one exact depth as magic, but it consistently shows that stopping well short of parallel leaves quad growth on the table compared to squatting to at least around 90 degrees of knee flexion or below.

Why don't squats build the hamstrings much?

Because of what the exercise actually asks of them. Squats are a knee-dominant, quad-focused movement, the hamstrings work mostly as stabilizers rather than as the primary muscle doing the lifting. Real hamstring growth comes from hip-dominant hinge movements, like Romanian deadlifts or good mornings, that load the hamstrings through a long stretched range of motion, or from a leg curl that isolates them directly. A leg routine built only around squatting tends to develop the quads while leaving the hamstrings comparatively behind.

Why do legs look uneven even with consistent training?

Often because bilateral barbell exercises let a stronger leg compensate for a weaker one without it being obvious. In a back squat or leg press, both feet share the load, so a real strength or size difference between legs can go unnoticed for a long time. Single-leg exercises, like Bulgarian split squats, walking lunges, or single-leg leg press, force each leg to handle its own load independently, which tends to surface imbalances quickly and gives the weaker leg the direct, undivided volume it needs to catch up.

How many sets do legs need each week?

Somewhere around 10 to 20 direct sets per week for quads, and a similar range for hamstrings, works as a starting point for most lifters, in line with other major muscle groups. Because legs cover several large muscles at once, quads, hamstrings, and to some extent glutes and calves, total weekly leg volume across all of it often adds up to more than what a single smaller muscle group needs.

What rep range works best for leg growth?

Legs respond across a wide range of rep counts, similar to most other muscle groups, provided sets are taken reasonably close to failure. Heavier, lower-rep squatting in the 5 to 10 range builds strength that supports long-term size gains, while higher-rep work in the 10 to 20 range on leg press, leg extensions, and leg curls adds volume without the same joint and recovery cost as always squatting heavy.

How often should you train legs for growth?

About twice a week for most lifters. Splitting squatting and hinging volume across two sessions rather than one long leg day gives the quads and hamstrings more frequent stimulus and more time to recover between sessions, which tends to matter more here than for smaller muscle groups given how fatiguing a genuinely hard leg session is. This often fits naturally into a push-pull-legs or full-body split that already includes two leg-focused sessions a week, alongside dedicated work for bigger glutes if that's a separate priority.

Knowing whether your legs are actually getting bigger, rather than just feeling wrecked after a session, comes down to whether your squat depth, weight, and hinge numbers are trending up over weeks and months. Ori logs every set and rep automatically, so that trend is sitting in your training history instead of something easy to lose track of on the muscle groups that take the most work to train well in the first place.

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FAQ

Does squat depth actually matter for quad growth? Yes, research points that direction. A study by Bloomquist and colleagues found greater quad growth from squatting to around 120 degrees of knee flexion compared to a shallower squat limited to 60 degrees. Other work by Kubo and colleagues found quad growth was similar between a 90-degree and 140-degree squat, though the deeper squat produced more growth in the glutes and adductors. Across this research, shallow, partial squats tend to undertrain the quads compared to squatting to at least parallel.

Do squats train hamstrings too? Only a little. Squats are quad-dominant, and while the hamstrings assist as stabilizers, they don't get loaded through a long range of motion the way they do in a hip hinge. Building hamstring size specifically usually requires a dedicated hinge movement like Romanian deadlifts or a leg curl, not more squatting.

Why do my legs look uneven even though I only do barbell exercises? Because a barbell movement like a back squat lets a stronger leg quietly do more of the work while both feet share the load. Single-leg exercises, like Bulgarian split squats or walking lunges, force each leg to handle its own weight and tend to expose and correct imbalances that bilateral exercises can hide.

How many sets a week do legs need to grow? Somewhere around 10 to 20 direct sets per week for quads and a similar range for hamstrings works for most lifters, split across squatting, hinging, and some single-leg or isolation work. Legs are made up of several large muscle groups, so total weekly volume across all of it often ends up higher than for a smaller muscle group trained alone.

How often should you train legs for the best results? About twice a week for most lifters. Splitting squatting and hinging volume across two sessions instead of one gives the quads and hamstrings more frequent stimulus and more time to recover, which matters more here than for smaller muscle groups given how fatiguing a hard leg session can be.