All the persons have the textiles capable of getting injured for intrinsic weakness, surcharge or biomechanical factors.

The intrinsic weakness refers to that every person has an anatomical shape that favors certain injuries and not others. For example the persons with lordosis lumbar exaggerated (sobreestiramiento of the column) have a high risk of enduring waist pain when they do sports of turning the trunk (golf, tennis, etc...), and the persons with pronación excessive of the feet (knock-kneed feet) can present pain in the knee when they cover long distances.

Without the correction adapted in every case, the risk of chronic injury it is raised because in all the sports repetitive specific movements take place.

The pain usually disappears when the activity gives in, but it reappears whenever it is resumed for the same personal reasons.

The foot dug it has a very high arch. Many people who seems to have a foot dug it has in fact a normal arch with a rigid ankle, for what the pronación is very scarce. These feet absorb badly the impacts, therefore the break risk increases for surcharge in the bones of the foot and the leg.

The most frequent cause of muscular injury or articulating is the excessive use of a muscle or muscular group. If the pain is continued by the exercise when it appears it is possible to worsen the injury. The excessive use can owe not to respect the rest of at least 48 hours after an intense exercise, independently of the preparation grade.

Whenever the muscles surrender to effort, some fibres get injured and others use the available glucógeno. Because only not disabled or those fibres that preserve a function glucolítica suitable work well, the intense exercise requests the same effort for less fibres, increasing the injury probability. The fibres are late 48 hours in recovering and moreover to restore the glucógeno. The sportsmen who work every day must submit to the effort to the different regions of the body.

Most of the methods of training gather the beginning of difficult - easy, that is to say, intense exercise one day (to run to a rhythm of approximately 2 km in 5 min) and with a slower rhythm the following day (2 km in 6 to 8 min). If a sportsman trains two times a day, every intense work must follow of three light efforts. Only the swimmers can tolerate an intense effort and lighter other every day. Possibly, the flotabilidad of the water helps to protect his muscles and joints.

The muscles, sinews and ligaments can get injured when they are weak for the exercise (they can become stronger by means of resistance exercises, with progressive weight). The bones can weaken for osteoporosis. The joints get injured with more frequency when the muscles and ligaments that stabilize them are weak.

The biomechanical factor that produces with more frequency injuries in the foot, leg or hip is the excessive pronación (draft of the foot after contacting with the soil) during the career. After the pronación, the foot turns towards the face to plant side street (supinación), later it rises on the fingers before detaching of the soil and displacing the weight towards another foot. The pronación helps to prepare the injuries distributing the force of the impact against the soil. The excessive pronación can produce injuries for an excessive medial draft of the low area of the leg, provoking pain in foot, leg, hip and knee. The ankles are so flexible that, during the deambulación or career, the arches touch the soil doing that this one seems slightly deep or stays away.