Doing leg presses and leg extensions for 12 weeks both make your main thigh muscles bigger in about the same way, but only leg extensions make the front part of your thigh (rectus femoris) grow significantly.

31

Pro

0

Against

Evidence from Studies

Supporting (1)

31

Community contributions welcome

31

Hypertrophic Effects of Single- versus Multi-Joint Exercise: A Direct Comparison Between Knee Extension and Leg Press.

Randomized Controlled Trial

Human

2026 Feb 5

The study found that both leg press and knee extension make the main thigh muscles bigger in similar ways, but only knee extension makes the front part of the thigh (rectus femoris) grow — just like the claim said.

Contradicting (0)

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

Hypertrophic Effects of Single- versus Multi-Joint Exercise: A Direct Comparison Between Knee Extension and Leg Press.

Score: 31

DOI: 10.1249/MSS.0000000000003957

Similar Assertions

Doing leg presses and leg extensions for 12 weeks both make your main thigh muscles bigger about the same amount, but leg presses also make your butt and inner thigh muscles grow more, while leg extensions make the front part of your thigh (rectus femoris) grow much more.

31

0

90%

If you want to make the front part of your thigh (rectus femoris) bigger, leg extensions work better than leg presses — after 12 weeks, leg extensions made it grow 12% more than leg presses did.

31

0

86%

Leg presses make your butt and inner thigh muscles bigger, but leg extensions don’t affect those muscles at all.

31

0

81%

Doing leg extensions makes the front thigh muscle bigger along its whole length more than doing squats, especially near the knee.

48

0

81%

Leg presses make your butt and inner thigh muscles bigger, but leg extensions don’t affect those muscles at all.

31

0

80%