BACKGROUND:The isokinetic muscle strength test system can quantitatively testtheshoulder flexor and extensormusclesand objectively analyze the relationship between size and balance of flexor and extensor.Therefore,itcould be used forstrength trainingmonitoringas wel asprediction and rehabilitation of sports injuries. OBJECTIVE:To understand shoulder flexor and extensor strength characteristics of adolescent softbal players, and find out shortcomings in the shoulder flexor and extensor strength to provide guidance for adolescent athletes’ strength trainingandpoint out possible sports injury risks caused by imbalanced strength. METHODS:ISOMED2000 isokinetic testing system(D&R,Germany)was employedto test theisokinetic strengthofshoulderflexor andextensor of12adolescentfemalesoftbal playersfromShanghaiSports University, China. RESULTS AND CONCLUSION:With the increase of test speed, the bilateral shoulder flexor and extensor peak torque, the flexor and extensor average power ratio,andthe flexor and extensor powers were reduced, but the flexor and extensor average power was on the rise. Under the same test speed,flexor and extensor peak torque, the flexor and extensor peak torque ratio, the flexor and extensor average power, the flexor and extensor average power ratio and the flexor powersof the throwing shoulderwere significantly larger thanthoseofthenon-throwingshoulder(P< 0.05), whiletheextensor peak torque and the extensor average powerof thethrowingand non-throwing shouldersshowedno significant differences (P> 0.05).Under the same test speed, bilateral shoulder homonymous flexor strength ratio was larger than that of the extensor, andthe extensor powerof the throwing shoulderwas less thanthatof the non-throwingshoulder.The ratio ofhomolateralshoulder flexor and extensor ranged from 70% to 80%. These results indicate that there is a significant difference betweentheflexor strength ofthebilateral shoulders inadolescent softbal players,but the bilateralextensor strengthis similar.Flexor fast strength and extensor maximum strengthof the throwing shoulderare lower. Besides, the isokinetic muscle strength test system canbe used toevaluate the flexor and extensor strengthinadolescent softbal athletes,based on whichcoachescangivetargetedstrength traininginadolescent softbal athletes.

BACKGROUND:Generaly, higher transcutaneous oxygen pressure indicates stronger aerobic fitness. Decreased transcutaneous oxygen pressure and increased transcutaneous carbon dioxide pressure reflect severe fatigue, muscle hypoxia, and poor function state.
OBJECTIVE:To observe changes in transcutaneous oxygen pressure and transcutaneous carbon dioxide pressure in biceps brachi of excelent male rowing athletes during 6-week altitude training, and analyze relationship of the changes to training load.
METHODS:The training containsthreestages,i.e., before, during and after altitude training. Transcutaneous oxygen pressure and transcutaneous carbon dioxide pressure were determined using PeriFlux System 5000 laser Doppler flowmetryin athletesintheresting-fasting state in the morning. Lactic acid level in athletes was determined using 6-grade load test 1 week before altitude training and 2 weeks after the end of altitude training.
RESULTS AND CONCLUSION:Transcutaneous oxygen pressure and theratio of transcutaneous oxygen pressure to transcutaneous carbon dioxide pressure showed the W-shape change, and transcutaneous carbon dioxide pressure showed the V-shape change. These results suggest that the arrangement of the altitude training program is suitable, namely“reserve physical fitness at the plain stage, add amount and enhance degrees of altitude training load at the early and late stages”,andit can provide a better training load structure model for the post-altitude training. Transcutaneous oxygen pressure and transcutaneous carbon dioxide pressure, in particular the ratio of them,canbeused to evaluate the degree of exercise load that athletes receive. At the same time, capilaries oxygen can be quantified by testing transcutaneous oxygen pressure.Transcutaneous oxygen pressureis recommendedas a noninvasive index to monitor changes in aerobic capacity of athletes.

Objective To investigate the incidence of exercise-induced bronchospasm(EIB)in athletes of winter sports in China,compare the incidence among athletes of different sports,genders and sports levels,and analyze the physiological differences in pulmonary ventilation function and blood in-flammatory factors between EIB and non-EIB athletes.Methods Ninety athletes(48 males and 42 fe-males)of four Winter Olympic events of cross-country skiing,short track speed skating,snowboard-ing,and freestyle skiing were recruited(including 61 national grade-2,20 national grade-1,and 9 na-tional excellent athletes).Venous blood was collected early in the morning on the test day for inflam-matory factor analysis.Moreover,the bronchial exercise provocation test was performed on the test day and pulmonary ventilation function parameters were obtained immediately before the test and at 1st,3rd,5th,7th,10th and 15th minute after the test.Results Thirty-three athletes were detected EIB out of 90,with a mean prevalence of 36.67%.In terms of incidence,athletes of cross-country skiing ranked the first(43.18%),followed by those of short track speed skating(38.46%),snowboarding(31.25%)and freestyle skiing(23.53%).Moreover,the incidence of female and male athletes was 42.86%and 31.25%,respectively.Meanwhile,the prevalence of national excellent sportsmen was 55.56%,followed by that of the national grade-1(40%)and grade-2(32.8%).According to the pulmo-nary ventilation indexes,the 1 s expiratory force volume(FEV1)and expiratory force volume(FVC)de-creased significantly(P<0.001)at the 1st and 3rd minutes after the provocation test among EIB ath-letes,but did not change significantly among the non-EIB athletes.Moreover,the FEV1/FVC ratio showed a downward trend among EIB athletes,but an upward trend among the non-EIB ones.As to the blood parameters,the level of the white blood cell count(109/L),interleukin-6 and CC16 of EIB athletes were significantly higher(P=0.02 and P=0.003),while that of immunoglobulin E(IgE)was low-er than the latter(P=0.07).Conclusion EIB troubles athletes of winter sports in China,characterized by a higher incidence among physical sportsmen than skill ones,among women than men,and high-level athletes than common ones.Moreover,inflammation of EIB athletes is more severe than the non-EIB ones,and partly due to airway injury.