The Claim
Do leg presses and leg extensions build the same thigh muscles, or do they target different ones?
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
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.
See the scientific wording
In untrained adults, 12 weeks of leg press training at 70% one-repetition maximum, performed twice weekly, is associated with similar increases in total quadriceps femoris volume (+4.9%) as knee extension training (+7.1%), but leg press produces significantly greater hypertrophy in the gluteus maximus (+15.4%) and adductor magnus (+6.2%), while knee extension produces significantly greater rectus femoris hypertrophy (+13.2% vs. +1.1%).
What the research says
1 studyThe study found that leg press and knee extension both made the front thigh muscles bigger about the same amount, but leg press also made your butt and inner thigh muscles grow more, while knee extension made one specific thigh muscle (rectus femoris) grow much more — just like the claim said.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.