The Journal of sports medicine最新文献

The morphology and function of synovial membrane is considered for its roles in development of traumatic joint effusions. Careful diagnostic study, including analysis of synovial fluid, is needed to be certain that one is dealing with uncomplicated traumatic effusion. Conservative treatment with cold application, rest and aspiration, seems effective and in line with known, basic experimental work for this generally self-limiting problem.

In general, the literautre review provides theoretical explanations for the popular, common-sense belief that a little stress improves performance, whereas when stress becomes severe, performance declines and ultimately breaks down. In terms of psychological stress (as opposed to physiological) the single most important variable appears to be the subject's interpretation of the stress-producing stimuli. Increases in adrenaline and noradrenaline accompany a variety of emotional responses, but differential proportions are not seen as characterizing the various emotions. Noradrenaline secretion appears to be related to physiological stress, or the amount of work attempted by the organism. Adrenaline secretion seems to be more-directly related to mental stress and emotional response. As emotional involvement increases, adrenal medullary secretion of adrenaline increases. The accompanying physiological and metabolic responses faciltate performance to a point; however, extremely high levels of arousal may adversely affect the athlete's proficiency. This is expecially true of sport skills requiring steadiness, precision, and concentration. Finally, for the sake of perspective, it should be stated that any contribution or complication created by the catecholamines is minimal when the entire ability range of competitors is considered. Whereas near superhuman feats by ordinary individuals caught in life-threatening situations have been reported, variations of great magnitude are unlikely in sport. The average individual is not transformed into a world class athlete merely by "getting the adrenaline flowing." Among athletes of similar physical stature and physiological function, however, adrenaline and arousal may certainly tip the scale of performance in sport.

Pulse rate and oxygen consumption were measured for 19 boys (agen 12-13) assigned to either Distance, Interval, or No-Training regimens, during a 5 min. run at 6 m.p.h., zero % grade on a motor driven treadmill prior to a 12 week conditioning period, following conditioning, and after four months of deconditioning. Oxygen consumption was assessed by opencircuitry and heart rate monitored by direct electrocardiography. Both conditioning groups significantly improved cardiovascular fitness (Distance group: 175-152 beats/min. and Interval group: 175-159 beats/min.) at P less than .01, but no differences were noted between them. They differed significantly from the Control group (P less than .05) which showed no change (172-173 beats/min.). No significant differences occurred between any of the groups for Vo2 variables, but Within group analysis statistically favored the Distance group. Post-conditioning and -deconditioning comparisoms indicated taht deconditioning had a deleterious effect on cardiorespiratory function. Cardiorespiratory fitness improved to the extent that competitive running events of 2-6 miles are suggested for this age group, but as the data indicated, only after sufficient training. Task similarity of training and standard test and running volume apparently afforded a slightly greater improvement of cardiorespiratory fitness in the Distance group. Marked deterioration of fitness during deconditioning was attributed to complete absence of a training stimulus.

An interesting fracture of the fibula is described which occurs very close to the radiographic isthmus of the bone. This fracture is produced by a rotational maneuver but does not result in a rotational type injury. It is our conclusion that these fractures were produced by a force distributed along the long axis of the fibula and bear a direct relationship to that fibula's anatomical ability or inability to transmit the force required of it at the moment of forcible dorsiflexion of the foot.