If your ability to bend forward were to be tested casually or even objecl ely with devices that measure how far forward you can reach in a sitting for ¡rd bend, little or no distinction would be made between how much of iat flexibility is in the hips and how much is in the lower back.
[Technical note: Under these circumstances, no consideration would be given I the possihle role of sacroiliac movements. That's just as well, because whether nul ion or counternutation is more significant will depend on the person: nutation u be more prominent in those who have good hip flexibility, and counternutation « be more characteristic of those who have to bend mostly from the waist. Saci 'iac movements take care of themselves naturally and will therefore be ignored 1 the following discussion.|
If you are unusually flexible and can lay your chest down against >ur thighs while keeping the knees straight, we can estimate that the rst stage of the bend will be about 120° of flexion at the hip joints and tha he second stage will be about 6o° of flexion in the back. The fact that som >ne who is this flexible can bend twice as much in the hips as in the lui spine gives some idea of how important hip flexibility is to forward bei inf?
in general, and it also accounts for why yoga teachers place so n ich
emphasis on it: they know how useful hip flexibility is to them personally. Here we'll focus on its main impediments—hamstrings and adductors—for those who are not so flexible.
the hamstring muscles
The hamstring muscles include the biceps femoris, the semimembranosus, and the semitendinosus muscles, and except for the short head of the biceps femoris, which takes origin from the femur, they all take origin from the ischial tuberosities and run from there along the rear of the thighs all the way to the bones of the leg—the tibia and fibula (figs. 3.10b. 8.9-10, and 8.12).
Because the hamstring muscles bypass the distal end of the femur, flexing the knee joint brings their insertions closer to their origins and releases tension throughout the backs of the thighs during any forward bend. Extending the knees in a forward bend, on the other hand, stretches the hamstrings and generates tension that pulls on the underside of the pelvis. This in turn makes it difficult to rotate the top of the pelvis forward (in an anterior pelvic tilt) and remove tension from the flexed-forward lumbar region.
A simulation of these effects in a flexible young man will clarify the role of the hamstrings in forward bending. First he should lie supine with one knee straight and the other knee flexed, and then he should draw the bent knee toward the chest without pulling it so far that the pelvis is lifted away from the floor. Keeping the knee flexed relieves hamstring tension so effectively that the hip can now be flexed through a range of about 150° from its supine starting position, creating a 30° angle with the floor 1 fig 6.3). Then as he extends the knee, the hamstring muscles will first be pulled taut and then force a partial extension of the thigh to a less acute angle, perhaps to a nearly straight up 8o° (fig. 6.4). This means that when his knees are extended the hamstrings limit hip flexion by 50°.
Some of the adductor muscles of the thigh (figs. 2.8,3.8-9, and 8.13-14) have a hamstring character. That is, in addition to drawing the thighs together they pull them posteriorly. And since some segments of the adductors 'chapter 4) take origin on the inferior pubic rami near the ischial tuberosities 'chapter 3), it is obvious that they will limit forward bending exactly as the hamstrings do—by exerting tension on the underside of the pelvis and Ceating a posterior pelvic tilt. It is also plain that the adductors will be Wretched the least when the thighs are together and the most when the feet are wide apart. Therefore, with the thighs adducted, the limitations to "ip flexibility are mostly from the hamstrings (figs. 3.10b, 8.9-10, and 8.12).
3.W ANATOMY OF HATHA \OCA
Abducted, any additional restriction to forward bending can only be fi TO the adductors. How this operates depends on the person. As shown hi e, the adductors limit hip flexion the most in those who start with less ,p flexibility (figs. 6.5-6).
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Yoga is extensively know as a form of exercise that stretches and strengthens the body through various poses know as ASANA. For other people yoga is the realization of inner self satisfaction. For other it is a religion that the believe and must follow. Learn more within this guide by downloading today.