Resistance applied during seated leg extensions isolates and strengthens the quadriceps muscle group. This resistance can be provided through various mechanisms, including stacked weight plates, air pressure, or hydraulic systems. A typical setup involves adjusting a pin or lever to select the desired load.
Developing strong quadriceps is essential for functional movements like walking, running, and jumping. Targeted exercises like leg extensions contribute to improved lower body strength and stability, potentially reducing the risk of knee injuries and enhancing athletic performance. Historically, strength training machines like the leg extension machine have evolved significantly in design and functionality since their inception, offering safer and more effective methods for isolating muscle groups.