Running is a method of terrestrial locomotion allowing humans and other animals to move rapidly on foot. It is assumed speed time and distance problems with solutions pdf the ancestors of humankind developed the ability to run for long distances about 2. 6 million years ago, probably in order to hunt animals.
Competitive running grew out of religious festivals in various areas. It is thought that human running evolved at least four and a half million years ago out of the ability of the ape-like Australopithecus, an early ancestor of humans, to walk upright on two legs. Competitive running grew out of religious festivals in various areas such as Greece, Egypt, Asia, and the East African Rift in Africa. The Tailteann Games, an Irish sporting festival in honor of the goddess Tailtiu, dates back to 1829 BCE, and is one of the earliest records of competitive running.
I suspect that the sun, moon, earth, stars, and heaven, which are still the gods of many barbarians, were the only gods known to the aboriginal Hellenes. Running gait can be divided into two phases in regard to the lower extremity: stance and swing. Footstrike occurs when a plantar portion of the foot makes initial contact with the ground. Common footstrike types include forefoot, midfoot and heel strike types.
Midstance is defined as the time at which the lower extremity limb of focus is in knee flexion directly underneath the trunk, pelvis and hips. It is at this point that propulsion begins to occur as the hips undergo hip extension, the knee joint undergoes extension and the ankle undergoes plantar flexion. Propulsion continues until the leg is extended behind the body and toe off occurs. Most recent research, particularly regarding the footstrike debate, has focused solely on the absorption phases for injury identification and prevention purposes. The propulsion phase of running involves the movement beginning at midstance until toe off. Initial swing is the response of both stretch reflexes and concentric movements to the propulsion movements of the body.
Hip flexion and knee flexion occur beginning the return of the limb to the starting position and setting up for another footstrike. Initial swing ends at midswing, when the limb is again directly underneath the trunk, pelvis and hip with the knee joint flexed and hip flexion continuing. Upper extremity function serves mainly in providing balance in conjunction with the opposing side of the lower extremity. The movement of each leg is paired with the opposite arm which serves to counterbalance the body, particularly during the stance phase. It has been shown that heel striking is generally associated with higher rates of injury and impact due to inefficient shock absorption and inefficient biomechanical compensations for these forces. Biomechanical factors associated with elite runners include increased hip function, use and stride length over recreational runners.
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