Supine lift VS reverse crunch!
In abdominal muscle training, supine leg raising is a common action, and the action is also very simple:
Lie your body on your back on the floor, with your upper body slightly fixed and vertical. Lift your legs up to 90 degrees to the ground, and then lower them straight down. ”
Many articles state that this action is used to train the lower abdomen.
But in fact, the abdominal muscles are not dominant when lying on your back!
But in fact Above, this 90-degree leg raising movement really trains the "hip flexor muscles"!
Hip flexor muscles: iliopsoas, rectus femoris, sartorius
Animation: iliopsoas dominates hip flexion (Lift legs)
When muscles like the iliopsoas, rectus femoris, and sartorius contract, they can It is hip flexion. To put it simply, hip flexion means lifting the thigh upward
That is to say, most of the movements such as lying on the back and raising the leg are dominated by the hip flexor muscles! The abdominal muscles are not dominant!
Reverse crunches instead of lying on your back
The rectus abdominis is mainly responsible for The flexion of the spine and the posterior tilt of the pelvis allow the spine to bend when the lower body is fixed, and the pelvis tilts backward when the upper body is fixed!
So we need to add a backward tilt of the pelvis during the leg lift! The movement of abdominal curling can allow our abdominal muscles to participate more
At the same time, it is recommended to connect the hip joint and knee joint The joints are folded so that the lower back is flat on the ground. This posture will reduce the tension of your hip flexor muscles, passively shortening the hip flexor muscles, and let your abdominal muscles become the protagonist.
Gif. Demonstration:
Strength technique: Use the power of the rectus abdominis to drive the pelvis upward (posterior pelvic Lean), try to lift your knees to your chest!
Just let your pelvis return to the normal position! Then continue the movement