If you’re trying to develop the coveted “X-frame” look, spamming leg extensions might not be doing you any favors. At least, according to a new scientific study.
A Jul. 2024 paper examined how different lower-body exercises create “regional muscle development” in the legs — including and especially the part of the quadriceps that creates the so-called “quad sweep.”
We’ll unpack this paper’s findings, limitations, and give you some actionable advice to improve your quad sweep during your next bodybuilding leg workout.
The Best Exercise for Developing Your Quad Sweep
The paper in question was published on Jul. 12 by authors Burke et al. (1) Titled “Exercise Selection Differentially Influences Lower Body Regional Muscle Development,” their work aimed to:
- “…compare the effects of multi-joint vs. single-joint lower body exercise on regional muscular development of the quadriceps, and…”
- “…compare the effects of exercises performed at different knee-joint angles on hypertrophy of the triceps surae.”
(If you don’t wear a lab coat to work every day, your triceps surae are your calf muscles.) Burke and colleagues focused heavily on two specific parts of the quads; the largest part, the rectus femoris, and the vastus lateralis — the part that creates the quad sweep during bodybuilding poses.
Findings & Limitations
No beating around the bush: The authors alleged that the leg press created more regional hypertrophy in the outer part of the quadriceps in just two months than the leg extension. Here’s what Burke & Co. did:
- 30 subjects with strength training experience performed two different pairs of quad and calf exercises on each leg, separately, twice per week for two months.
Findings: The vastus lateralis, or the outer region of the quadriceps, responded better to compound exercises like the leg press.
Findings, Cont.: The rectus femoris muscle, which is also part of your quads, grew more during the leg extension.
Extra Credit: Participants’ calves grew more from doing straight-legged calf raises than seated calf raises. This finding has been repeated in other studies as well.
Limitations: While this study was mostly well-designed, 30 participants is still a relatively low number to draw broad conclusions from.
The authors also didn’t include other compound leg exercises like back, front, or hack squats to see if their findings were unique to the leg press — we’d wager they aren’t.
How To Build a Quad Sweep: Your Next Move
BarBend Expert and PhD bodybuilder Dr. Eric Helms discussed this paper on a recent episode of the Iron Culture podcast. Helms offered that the unique anatomy of the quadriceps partly explains why leg presses build your quad sweep, while leg extensions don’t.
- “There’s probably greater range of motion at the knee during leg presses or squats compared to leg extensions,” said Helms.
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But there’s more to it, according to Helms. Of your four quadriceps muscles (“quad”-riceps), only the rectus femoris is biarticular; it crosses both the knee and hip joints.
When your hip is flexed, like during a leg press, Helms theorized that the rectus femoris isn’t stretched to the same degree as the other parts of the quads that only affect the knee joint. Ergo, your vastus lateralis is tagged in to pick up the slack.
If you want to prioritize your quad sweep by applying the knowledge from this study, you might structure a quad-focused leg workout something like this:
- Warm-Up: 5-10 minutes on the treadmill, stair stepper, or bike
- Leg Press: 5 x 8-10
- Hack Squat: 3 x 12
- Leg Extension: 2 x 15
- Standing Calf Raise: 3 x 15
More Research Content
- Are Today’s Children Weaker Than Previous Generations?
- Strength Training Works Just as Well as Stretching for Flexibility
- Overhead Triceps Extensions Build Significantly More Muscle Than Pressdowns
References
- Burke, R., Piñero, A., Mohan, A.E. et al. Exercise Selection Differentially Influences Lower Body Regional Muscle Development. J. of SCI. IN SPORT AND EXERCISE (2024).
Featured Image: NassornSnitwong / Shutterstock
