Shock absorption during forefoot running and its relationship to medial longitudinal arch height.

Background: Overuse injuries to the lower extremity have often been connected with the repetitive loading of the foot and in particular its ability to absorb shock. The shock absorbing ability of the foot is thought to relate to its structure, particularly the height of the medial longitudinal arch. The purpose of this study was to investigate the shock absorption characteristics of the foot in forefoot running as measured by the dynamic load rate of the vertical ground reaction forces during the early stages of ground contact and to relate these characteristics to the height of the medial longitudinal arch.

Ischaemic preconditioning of skeletal muscle 2. Investigation of the potential mechanisms involved.

We have previously shown that prior exposure of rat hind limbs to ischaemia for five minutes and reperfusion for five minutes reduced the structural damage to skeletal muscle which followed a subsequent period of ischaemia for four hours and reperfusion for one hour. We have now examined the potential mechanisms by which this ischaemic preconditioning protocol may be effective in reducing damage to skeletal muscle induced by prolonged ischaemia and reperfusion. Prior exposure of the hindlimb to ischaemia for five minutes and reperfusion for five minutes did not prevent the fall in the ATP content of tibialis anterior which occurred after a subsequent period of ischaemia for four hours and reperfusion for one hour.

Ischaemic preconditioning of skeletal muscle. 1. Protection against the structural changes induced by ischaemia/reperfusion injury.

Ischaemic preconditioning is a process by which exposure of a tissue to a short period of non-damaging ischaemic stress leads to resistance to the deleterious effects of a subsequent prolonged ischaemic stress. It has been extensively described in the heart, but few studies have examined the possibility that it can occur in skeletal muscle. We have used a rat model of ischaemia of one limb to examine this possibility.