09/03/2026
These two exercises complement each other perfectly for complete upper leg development.
The leg extension loads the quads through knee extension with virtually no hamstring involvement. It is the most direct quad isolation exercise available and the only one that meaningfully trains the re**us femoris.
The leg curl loads the hamstrings through knee flexion with virtually no quad involvement. It is the most direct hamstring isolation exercise available and the only way to train the biceps femoris short head which no hip hinge movement can reach.
Together they cover both sides of the upper leg completely. If your leg session only includes compound movements like squats and deadlifts both the re**us femoris and the biceps femoris short head are likely being undertrained. Adding both of these to your program covers the gaps that compound movements leave behind.
