The common method for leg extensions involves an upright back with the seat adjusted so hips are flexed at approximately 90 degrees. However, an alternative technique uses a reclined torso with the seat further back, resulting in a hip flexion of around 40 degrees. Which method yields superior quad development? A recent study investigated this very question, comparing the effects of these two leg extension variations. Participants were assigned to either the upright seated position (90-degree hip flexion) or the reclined position (40-degree hip flexion) for a 10-week training period. Surprisingly, there was no significant difference in overall quadriceps growth between the two groups. However, one crucial distinction emerged: the rectus femoris, a prominent quadriceps muscle, exhibited significantly greater growth (170% more) in the reclined group.
While this difference appears substantial, it’s important to note the actual muscle gain was minimal, measured in millimeters. Nevertheless, accumulating these small gains over years of consistent training can potentially lead to noticeable improvements. Therefore, performing leg extensions with a reclined torso and the seat back may contribute to maximizing long-term quadriceps development, especially for the rectus femoris.
