The rectus femorisbiarticular muscle acting over the hip has a smaller hip moment arm than the hamstrings. However, the rectus femoris moment arm is greater over the knee than the hamstring knee moment. This means that contraction from both rectus femoris and hamstrings will result in hip and knee extension. Hip extension also adds a passive stretch component to rectus femoris, which results in a knee extension force. This paradox allows for efficient movement, especially during gait.
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In human anatomy, a hamstring is any one of the three posterior thigh muscles in between the hip and the knee. The hamstrings are quite susceptible to injury.
In human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the lower limb.
The quadriceps femoris muscle is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the great extensor muscle of the knee, forming a large fleshy mass which covers the front and sides of the femur. The name derives from Latin four-headed muscle of the femur.
Biarticular muscles are muscles that cross two joints rather than just one, such as the hamstrings which cross both the hip and the knee. The function of these muscles is complex and often depends upon both their anatomy and the activity of other muscles at the joints in question. Their role in movement is currently poorly understood.
The patellar reflex or knee-jerk is a stretch reflex which tests the L2, L3, and L4 segments of the spinal cord.
Hamstringing is a method of crippling a person or animal so that they cannot walk properly by severing the hamstring tendons in the thigh of the individual. It is used as a method of torture, or to incapacitate the victim.
Osgood–Schlatter disease (OSD) is inflammation of the patellar ligament at the tibial tuberosity (apophysitis). It is characterized by a painful bump just below the knee that is worse with activity and better with rest. Episodes of pain can last a few weeks to months. One or both knees may be affected and flares may recur.
The biceps femoris is a muscle of the thigh located to the posterior, or back. As its name implies, it has two parts, one of which forms part of the hamstrings muscle group.
The vastus medialis is an extensor muscle located medially in the thigh that extends the knee. The vastus medialis is part of the quadriceps muscle group.
The vastus intermedius (Cruraeus) arises from the front and lateral surfaces of the body of the femur in its upper two-thirds, sitting under the rectus femoris muscle and from the lower part of the lateral intermuscular septum. Its fibers end in a superficial aponeurosis, which forms the deep part of the quadriceps femoris tendon.
The semitendinosus is a long superficial muscle in the back of the thigh. It is so named because it has a very long tendon of insertion. It lies posteromedially in the thigh, superficial to the semimembranosus.
The rectus femoris muscle is one of the four quadriceps muscles of the human body. The others are the vastus medialis, the vastus intermedius, and the vastus lateralis. All four parts of the quadriceps muscle attach to the patella by the quadriceps tendon.
An anterior cruciate ligament injury occurs when the anterior cruciate ligament (ACL) is either stretched, partially torn, or completely torn. The most common injury is a complete tear. Symptoms include pain, a popping sound during injury, instability of the knee, and joint swelling. Swelling generally appears within a couple of hours. In approximately 50% of cases, other structures of the knee such as surrounding ligaments, cartilage, or meniscus are damaged.
The tuberosity of the tibia or tibial tuberosity or tibial tubercle is an elevation on the proximal, anterior aspect of the tibia, just below where the anterior surfaces of the lateral and medial tibial condyles end.
Biceps femoris tendon rupture can occur when the biceps femoris is injured in sports that require explosive bending of the knee as seen in sprinting. If the athlete is fatigued or has not warmed up properly he/she may suffer a hamstring strain/rupture, which is the tearing of the hamstring muscle. Avulsion of the biceps femoris tendon is the complete pulling away of the tendon from the bone. This most commonly occurs where the long head attaches to the ischial tuberosity. Injuries to biceps femoris are more common than to other hamstring muscles.
Straining of the hamstring, also known as a pulled hamstring, is defined as an excessive stretch or tear of muscle fibers and related tissues. Hamstring injuries are common in athletes participating in many sports. Track and field athletes are particularly at risk, as hamstring injuries have been estimated to make up 29% of all injuries in sprinters.
Terrestrial locomotion by means of a running gait can be accomplished on level surfaces. However, in most outdoor environments an individual will experience terrain undulations requiring uphill running. Similar conditions can be mimicked in a controlled environment on a treadmill also. Additionally, running on inclines is used by runners, both distance and sprinter, to improve cardiovascular conditioning and lower limb strength.
A kick is a skill in association football in which a player strikes the ball with his or her foot. Association football, more commonly referred to as football and also known as soccer, is a sport played world-wide, with up to 265 million people around the world participating on a yearly basis. Kicking is one of the most difficult skills to acquire in football. This skill is also vitally important, as kicking is the way in which passes are made and the primary means by which goals are scored.
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