In the traditional gym setting, the leg curl is often considered a staple of lower body strength training. It is an isolation exercise (a single-joint movement), knee flexion, used to strengthen the hamstrings.
This exercise is useless because you never use this particular muscle action, isolated knee flexion, lying on your stomach, in everyday activities and in sports. So the leg curl is not functional; it has no purpose.
In activities like running, jumping and skating, for example, the function of the hamstrings is not to flex the knee, but to extend the hip. So to develop functional strength for these activities, you should do hip extension exercises where your foot is in contact with the ground. This is known as a closed chain exercise. An open chain is when your foot is not in contact with the ground, such as when your leg is bent.
One more point is that the hamstrings don’t work in isolation; They work together with the glutes (glutes) in almost all movements. Exercises like the stiff leg deadlift and especially the single leg stiff leg deadlift, which strengthen the glutes and hamstrings, are great functional movements because they work the muscles in a way that you really use them in your activities and sports everyday.
The key to correctly performing the stiff-leg deadlift and the single-leg stiff-leg deadlift is to focus on bending your hips while pushing your butt back and maintaining an arch in your lower back. If you remember that the movement comes from the hips and not the lower back, you will perfect your technique and perform this lift correctly.