There are several different types of squats. Some are done just with ones own body weight, while others may use a barbell. Both of these squat variations demonstrate the movement of a dynamic squat. During a squat an individual will begin in an upright position. Since the squat is a closed chain movement, both feet are on the ground simultaneously throughout the entire movement. In this position both the hips and knee begin in extension. As the individual begins the downward squatting motion their hip, knee and ankle will move from extension and into flexion. The lifter will then continue with this motion until they have reached their assigned or desired depth. Typically the lifter will squat until their thighs become parallel with the ground. …show more content…
This entire motion down is know as the eccentric movement of the squat. As the body is lowered the gluteus maximus and the hamstrings eccentrically flex the hip. At the same time the knee becomes eccentrically flexed, which is controlled by the quadriceps. The last joint that is moved eccentrically is the ankle, which is put into dorsiflexion by the calves. After this depth is met the lifter will use “over 200 muscles … which are activated during squat performance” (Schoenfeld et al, 2010) to return back to their starting upright position. This is the concentric movement. In this case the gluteus maximus and hamstrings work together to concentrically shorten to pull the hips forward and back into starting position. The knee is also concentrically extended to its starting straight position by the quads. The ankle also goes through the concentric movement changing from dorsiflexion to plantar flexion because of the shortening of the calf …show more content…
Females demonstrate a “more erect landing posture and utilize greater hip and ankle joint range of motions and maximum joint angular velocities compared to males”(Decker et al. 2003). There are several factors as to why female athletes moveland different than when compared with their male counterparts. Structural alignments such as an “excessive Q-angle, thigh-foot angle, genu recurvatum, femoral anteversion, smaller intercondylar notch width, decreased notch width index, and generalized joint laxity” (Hass et al 2005). A Q-angle of the knee is a measurement of the angle between the quadriceps muscles and the patella tendon and provides useful information about the alignment of the knee joint. Normal for men is 14 degrees and for women is 17 degrees. Women will usually have a higher Q angle due to their naturally wider pelvis and hips. Genu recurvatum is an alignment of the knee found in the sagittal plane. Although every person should have a little bit of hyperextension in the knee, too much can begin to cause problems within the knee. A person’s knee that bends backwards too far has an excessive extension occurring in the tibiofemoral joint. This too is more common in females than
In the frontal plane, the movement shows the depression of scapula. The joint involved in this part of the pirouette is the scapulothoracic joint. This motion can be analyzed in the frontal plane or the sagittal due to the movements of the shoulders with the trunk (Hall, 2011). In the transverse plane it is the external rotation of the hip that helps form a pirouette. The muscles used to perform the rotation are the gluteus minimus, piriformis, superior gemellus, inferior gemellus, obturator internus, obturator externus, and quadratus femoris (Hall, 2011). These muscles are used to help the leg move to the correct position for a pirouette.
J Orthop Sports Phys Ther 31; A-37. Nisell R. (1985) Mechanics of the knee: A study of joint and muscle load with clinical applications. Acta Orthop Scand 216; 1-42. Oatis C. (2009)
The incidence and prevalence rate of anterior cruciate ligament (ACL) injuries in female athletes continues to increase over time (Prodromos, Han, Rogowski, Joyce, & Shi, 2007). With the growing rate in the amount of young women participating in sports, data has shown that the rate of ACL injury increases linearly with this participation ("The Relationship Between Static Posture and ACL Injury in Female Athletes," 1996). This epidemic of ACL injuries in female athletes, young or old, continues to be problematic in the athletic world. This problem not only affects the athlete themselves, but also the coaches and the sports medicine community.
Tearing the ACL is now considered an epidemic in the United States over 100,000 recorded incidences are reported each year (Moeller). While such a finding may be good for orthopedic doctors and surgeons, this is not good for millions of athletes’ competing these days in high intensity sports. This is especially a problem for female athletes who are two to four times more likely to tear their ACL than men (Moeller). This is one of the biggest mysteries about ACL tears is the difference between the number of injuries seen in women and men. Women tend to tear there ACL far more frequently then men. While not everyone agrees that gender itself is the source of the problem, evidence is growing that females are learning too late that participating in sports can also become the first step to ruining an active lifestyle.
... activities differently. For example, females knees are more turned in towards the midline of the body. This is because they have a wider pelvic bone than males. Furthermore, females bend their knees a lot less than males when jumping and landing. When running and jumping, it is important to bend at the ankles, knees, and hips. This provides the body with a rigid support system. Females get ACL injuries because when they land, they “lock out,” that is, they straighten instead of bend their knees.
This experiment was completed in order to compare calf circumference as well as gender, weight, and jump height. If a person has larger calves, then they will likely be capable of reaching a higher vertical height. It can also be shown that if the person is a male, then they will be able to jump higher. A larger calf circumference is more likely to reflect a high vertical jump due to the fact that the fat content of the calves in the experiment was accounted for, therefore a large calf measurement in this experiment means a muscular calf. It is common knowledge that more muscle will result in stronger legs leading to a higher vertical. While it is believed that males are bigger, faster, and stronger, this leads us to believe that they can also jump higher. Males tend to have stronger muscles at nearly all points in life(Burr, 1997). That being said, the aforementioned hypotheses can be expected to be true because males are likely to have larger, and therefore stronger, calves. It can also be expected that males will display a higher vertical jump(Caruso, 2012).
The fighter is then ready to initiate the movement phase: extension at the knee with a relative angle to the thigh of about 180 degrees, lateral rotation of the grounded foot between 90 and 120 degrees, and additional lateral flexion of the spine.
“The anterior cruicate ligament is a strong band that arises from the posterior middle part of the lateral condyle of the femur, it passes anteriorly and inferiorly between the condyle, and is attached to the depression in front of the intercondylar eminence of the tibia (Mosby‘s page. 105).” The tear of the A.C.L is described as a partial or complete rupture of the anterior cruciate ligament. The A.C.L. does not repair by itself. It is so important to an athlete in most sports because an athlete has to be able to rotate the knee in specific directions. The tear happens more frequently in soccer, basketball, and volleyball. Athletes who started participating in a sport while they were young have a greater chance of sustaining a tear. Women are more susceptible to this injury than men. Theories for this include hormonal, environmental, and biomechanical factors. “Women‘s muscles react differently in landing. Doctors say that women land with straighter legs than men do; thus, they pass their shock to the A.C.L. resulting in a tear. Environmental factors are shoes and playing surfaces.” (Patrick, Dick)
Throughout literature countermovement jumps (CMJ) are seen to be higher in contrast to squat jumps (SJ) (Bobbert et al. 1996; Kubo et al. 1999; Bobbert et al. 2005). However present literature regarding the key potential mechanisms behind why greater muscle forces are seen accelerating the body upwards in CMJ in comparison to SJ is somewhat unclear. A CMJ can be defined as a positioning starting upright, beginning the descending motion in advance of the upward motion in contrast to a SJ where the start position is squatted with no preparatory countermovement (Akl 2013). The higher jump heights seen in CMJ in comparison to SJ are apparent even if at the start of propulsion phase the body configuration is identical (Bobbert et al. 1996). In past literature three main mechanisms have looked to provide an explanation for the greater muscle forces seen in CMJ than the SJ. The first plausible theory is that the muscle stretch in CMJ increases the production of force capability of the contractile machinery (Edman et al. 1978; Ettema et al. 1992; Herzog et al. 2003). Secondly the assumption that the muscle fibres are on the descending limb of their force–length relationship at the start of propulsion in the CMJ and SJ, however in CMJ the stretching of a chain of elastic components, they are not as far past optimum length therefore allowing a greater force over the initial phase of their shortening range, with the stretching of sequences of elastic components, this then causes the storage of elastic energy that is then reutilized in the propulsion phase (Ettema et al. 1992). The final explan...
The majority of ACL injuries suffered during athletic participation are of the noncontact variety. Three main noncontact mechanisms have been identified planting and cutting, straight-knee landing and one-step stop landing with the knee hyperextended. Pivoting and sudden deceleration are also common mechanisms of noncontact ACL injury. Basketball, soccer, and volleyball consistently produce some of the highest ACL injury rates across various age groups. Other activities with a high rate of injury are gymnastics, martial arts, and running. In most sports, injuries occur more often in games than in practice. Many injuries have occurred during the first 30 minutes of play. One-reason physicians are seeing more ACL injuries in female patients that more women play sports, and they play more intensely. But as they continued to do more studies, they are finding that women's higher rate of ACL is probably due ...
The focus of this paper is mechanically and automatically break down the deadlift. It focuses on the four phases of the deadlift (The lift off, pull through, the lockout, and the lowering phase) as well as the muscles involved in lifting and lowering the load. The sole purpose of the deadlift is for health and fitness. It is a core lift that works nearly every muscle in the body. Muscles from the lower and upper extremities will go through a period of flexion and extension when moving through the phases. The deadlift should be performed safely, and with proper form to avoid injury. This paper shows and demonstrates the proper form of the deadlift. There are also a number of forces acting on the load and the athlete. Gravity and external forces will be an active part of lifting the load. Images and tables are provided in the paper to better understand the movements and muscles used when performing the deadlift.
According to the “Physical Therapy Corner” (2007), “women suffered anterior cruciate ligament injuries more often than men, nearly 4 times as often in basketball, 3 times as often in gymnastics, and nearly 2 and a half times as often in soccer” (Knee Injuries section, para.1). There are various risk factors that contribute to the high rate of acquiring injuries to the ACL for female athletes. External factors such as improper shoe wear, skill of the player, and unstable playing surface may play a significant role in developing ACL injuries, but those factors are just hypothetical.... ... middle of paper ...
This skill involves jumping in the sagittal plane about the transverse axis. It consists of hip, knee, ankle, and shoulder joints. In the preparation phase in propulsion, the subject has flexed knees and hips which will need to be straightened by the strength of their corresponding joints such as the hinge joint at the knee joint. The hip joint is a ball and socket joint that bears the body weight and allows for jumping motion. During th...
Anterior knee pain plagues the athletic community, the most common being runner’s knee or patellofemoral pain syndrome (PFPS). One point or another in an athlete’s career they have experienced this kind of pain. When comparing between male and female athletes and who has the higher chance of knee pain, female athletes have a higher prevalence than male athletes (Dolak KL). There are several different mechanisms of patellofemoral pain a few being: pes planus,an increased Q angle, weak, tight or an imbalance in the quadriceps or hip muscles. Recently in my clinic site as the spring sports such as, baseball, soccer and track and field the athlete’s perform a lot of squatting, running, and kneeling which load the patellofemoral joint. We are now starting to see several and treat several athletes with patellofemoral knee pain. Each of them experiencing the pain from a different mechanism. As an athletic trainer we want to treat not only the symptoms, but the mechanism of injury to prevent further injuries down the road. If patellofemoral pain syndrome is not properly treated it can develop into chronic diseases such as chondromalacia or arthritis, maybe eventually leading to a total knee plan. (Lee SE) Treatment while the athletes are young and symptoms aren’t severe is key to preventing further injury.
The purpose of the squat is to train the muscles around the knees and hip joints, as well as to develop strength in the lower back, for execution of basic skills required in many sporting events and activities of daily living. Because a strong and stable knee is extremely important to an athlete or patient’s success, an understanding of knee biomechanics while performing the squat is helpful to therapists, trainers, and athletes alike (11). Because most activities of daily living require the coordinated contraction of several muscle groups at once, and squatting (a multi-joint movement) is one of the few strength training exercises that is able to effectively recruit multiple muscle groups in a single movement, squats are considered one of the most functional and efficient weight-bearing exercises whether an individual’s goals are sport specific or are for an increased quality of life