闭经运动员与月经期运动员相关生殖激素水平比较

目的:比较闭经运动员与有周期月经的运动员月经期中雌二醇(Estradiol,E2)、卵泡刺激素(Follicle-stimulating hormone,FSH)、黄体生成素(Luteinizing hormone,LH)、催乳素(Prolactin,PRL)、性激素结合球蛋白(Sex hormone-binding globulin,SHBG)及生长激素(Growth hormone,GH)水平的差异,探讨上述激素与运动性闭经的关系。方法:夏训开始2周后,对广东省体育运动技术学院专项训练2年以上、年龄14～21岁的女子运动员的月经史进行问卷调查。闭经运动员9人(原发性闭经3人,继发性闭经6人)为闭经组,在有周期月经的运动员中选与闭经组同一专项、年龄相似的运动员10人作为对照组(即周期月经组)。两组对象均身体健康,无生殖系统器质性病变,且近3个月未使用激素类药物。空腹肘静脉取血,时间为周期月经组月经期第2～4天,闭经组任选一日,且两组运动员取血前至少24～48小时内均无大负荷训练。放射免疫法测血清E2值,双抗夹心免疫放射法测血清FSH、LH、GH、PRL及SHBG水平。结果:两组运动员血LH、FSH及E2水平差异不明显,闭经运动员血液生殖激素水平相当于周期月经组运动员月经期即生殖激素生理性波动低值期水平。闭经组血PRL水平显著低于周期月经组,GH、SHBG水平显著高于周期月经组。结论:血PRL水平降低及SHBG水平升高可能与运动性闭经有关。     

青少年运动员21公里跑后血清心肌肌钙蛋白T亚基水平及心电图T波正常化观察

目的:观察青少年运动员21公里跑后心电图T波正常化(TWN),并结合特异性心肌损伤血清标志物——心肌肌钙蛋白T亚基(cTnT)探讨运动性TWN的意义。方法:24名青少年男子中长跑运动员(16.1±1.3岁)进行一次全力21公里跑。测定运动前后心电图及血清cTnT水平。识别TWN并比较TWN阳性与阴性者运动后血清cTnT水平。结果:运动后血清cTnT水平显著升高。11名运动员心电图出现TWN,其运动后cTnT水平与未出现TWN运动员无显著差异。结论:青少年运动员长距离耐力运动后TWN可能并不反映心肌损伤。     

优秀散打运动员专项训练课前后血清肌酸激酶活性变化

目的:观察优秀散打运动员专项训练课后血清肌酸激酶(CK)活性的变化,对运动员机能状况、训练效果进行科学监测和评估。方法:对22名男子散打运动员进行专项训练课当日晨起空腹安静时、专项训练课准备活动后、专项训练课后5min、次日晨及训练课后36h血清CK值的测定。用N-乙酰半胱氨酸激活法测定血清CK活性。结果:受试运动员准备活动后血清CK水平明显升高,这种升高趋势一直持续到次日晨,专项训练课后5min血清CK水平达到最高值,与当日晨比较差异非常显著(P<0.01)。结论:散打运动专项训练课后,血清CK活性具有升高时间早、幅度大的特点。     

间歇性低氧暴露对足球运动员自由基代谢的影响

16名北京体育大学体育系男子足球运动员随机分为对照组和实验组,对照组为常氧环境,实验组实施高住低训,观察间歇性低氧暴露及运动对机体自由基代谢的影响。结果:(1)对照组4周实验前后自由基代谢各指标无明显变化。(2)实验组运动前、10小时急性低氧暴露后与常氧运动前比较,血清CK明显升高,血清MDA及红细胞SOD活性有升高趋势,红细胞GSH明显下降,GSH-PX有下降趋势。(3)实验组4周低氧暴露运动前与常氧相比,血清CK进一步升高,红细胞SOD、GSH-PX有升高趋势,血清MDA无明显变化。(4)运动对自由基代谢的影响在常氧与低氧环境下无明显差异。     

运动员血清中黄体生成素生物活性与免疫活性的研究

对２８名普通男大学生，１４名男竞走运动员和２０名男短跑运动员安静状态的血清免疫活性黄体生成素（ＲＩＡ－ＬＨ）、生物活性黄体生成素（Ｂｉｏ－ＬＨ）及睾酮水平进行了测试，并分析了１４名男子足球运动员急性运动前、后Ｂｉｏ－ＬＨ，ＲＩＡ－ＬＨ和睾酮的变化。结果表明：（１）三组受试者Ｂｉｏ－ＬＨ与ＲＩＡ－ＬＨ呈正相关，三组之间的Ｂ／Ｉ比值和睾酮水平均无显著性差异，表明他们的垂体－性腺轴的分泌功能状况基本一致。（２）竞走运动员的ＲＩＡ－ＬＨ明显高于其他两组，而Ｂｉｏ－ＬＨ无显著性差异。提示：把Ｂｉｏ－ＬＨ和ＲＩＡ－ＬＨ结合起来。能更客观地评价ＬＨ的水平。（３）急性运动后，Ｂｉｏ－ＬＨ明显升高，而ＲＩＡ－ＬＨ变化不明显，表明运动使ＬＨ的成分发生改变。（４）急性运动后血清睾酮的升高，可能与ＬＨ生物活性升高有关。     

补充大蒜素对一次性大强度运动后青年女子足球运动员血清cTnI和CK-MBmass的影响

目的:观察大蒜素对青年女子足球运动员一次性大强度运动前后不同时相血清cTnI和CK-MBmass的影响。方法:青年女子足球运动员12名,随机分为对照组(n=6)和实验组(n=6)。对照组每天口服安慰剂80 mg,实验组每天口服大蒜素肠溶胶丸80 mg,2周后两组进行一次性大强度跑台运动,记录运动时间、跑动距离和运动中的最大心率。分别测定2周服药前和运动后4小时受试者血cTnI和CK-MBmass水平。结果:(1)两组运动员运动时间、运动距离和运动时最大心率的结果符合大强度运动的负荷特点,但两组间相比较差异无统计学意义。(2)运动后4小时两组血清cTnI较实验前均显著增加(P<0.05),实验组运动后4小时血清cTnI浓度显著低于对照组(P<0.05)。(3)运动后4小时两组血清CK-MBmass较实验前均降低,但无统计学意义,组间亦无显著性差异。结论:一次性大强度运动后青年女子足球运动员血清cTnI均显著增加,提示大强度运动导致心肌微损伤。实验组运动员血清cTnI低于对照组,提示大蒜素对减轻运动性心肌微损伤具有积极作用。     

男子田径运动员负重运动后外周血淋巴细胞凋亡的变化及其机制分析

目的:观察一次急性负重运动对外周血淋巴细胞凋亡的影响并探讨其可能机制。方法:16名青少年田径运动员负重(30%体重)进行一次急性离心运动,包括5 min台阶试验和15次蹲起。分别于运动前,运动后即刻,运动后2 h、4 h、8 h、12 h、24 h和48 h测定淋巴细胞凋亡率(流式细胞仪)、血清肌酸激酶(半自动生化仪)、血清皮质醇(γ放射免疫分析仪)、淋巴细胞Fas/FasL和Bax/Bcl-2(Western blot)。结果:淋巴细胞凋亡率在运动后呈先上升后下降的变化趋势,运动后24 h达峰值,其中运动后即刻,运动后2 h、4 h、8 h、12 h、24 h和48 h均较运动前显著性升高(均为P<0.01),运动后48 h较运动后24 h显著性下降(P<0.01);血清CK和Bax/Bcl-2亦呈先升高后下降的并行性变化趋势,其中运动后12 h、24 h和48 h均较运动前显著性升高(均为P<0.01),运动后24 h达峰值,运动后48 h较运动后24 h显著性下降(P<0.01,P<0.05);Fas/FasL在各时间点均无显著性变化(P>0.05);血清皮质醇在运动后即刻和运动后2h、4 h、8 h、12 h均较运动前显著性升高(均为P<0.01),运动后12 h达峰值,运动后24 h恢复至运动前水平(P>0.05)。结论:负重运动可诱导外周血淋巴细胞凋亡,其机制与运动性肌肉损伤、应激激素升高和线粒体氧化应激有关。     

牛初乳对优秀赛艇运动员强化耐力训练期免疫功能的影响

目的:探讨牛初乳对长时间强化耐力训练后运动员免疫功能抑制的调节作用。方法:将15名国家健将级赛艇男运动员随机分为运动对照组和牛初乳组。两组运动员同时进行30天内容相同的运动训练,训练期间牛初乳组以15g/d的剂量补充牛初乳。训练期前及训练期后分别测定各组运动员的各项免疫指标。结果:强化耐力训练期后,牛初乳组淋巴细胞数量明显增加,并显著高于运动对照组(P<0.001);CD3+T细胞和CD4+/CD8+比值维持在训练前正常水平,但均显著高于对照组(P<0.01);训练期后,牛初乳组血清球蛋白水平显著高于运动对照组(P<0.01),血清白蛋白及A/G比值却明显低于对照组(P<0.05)。强化耐力训练期后,牛初乳组与运动对照组中性粒细胞、巨噬细胞、IgA和IgG均无显著性差异。结论:强化耐力训练期补充牛初乳能有效防止强化耐力训练期后CD4+/CD8+比值的下降、淋巴细胞数量的减少及血清球蛋白含量的降低。提示牛初乳具有良好的维持机体免疫功能自稳态的作用,有助于防止长时间大强度耐力训练后运动员机体免疫功能的下降。     

优秀跆拳道运动员比赛前后及恢复期血清CK、LDH、SOD的变化

对 2 3名优秀跆拳道运动员比赛前后及恢复期血清肌酸激酶 (CK)、乳酸脱氢酶 (LDH)、超氧化物歧化酶 (SOD)进行研究。结果显示 :赛后 5min ,血清CK、LDH、SOD活性最大 ,均显著高于赛前 ;赛后 1小时CK、SOD较赛后 5min显著下降 ,恢复 2 4小时后继续下降 ,但仍显著高于赛前 ,表现出升高出现早 ,恢复速度慢的特点 ;赛后 1小时LDH较赛后 5min显著下降。结果表明 ,跆拳道比赛后及恢复期血清酶活性变化与比赛时间、运动强度、运动形式和赛后运动员身体机能状态、疲劳消除情况以及运动损伤等关系密切     

补充复合抗氧化剂对中长跑运动员身体机能的影响

目的 :观察运用复合抗氧化剂对耐力项目运动员促进体能恢复的作用。方法 :15名男性省级中长跑运动员随机分为对照组和实验组 ,进行为期 3周的大强度训练 ,实验组每天早晚各补充 10ml复合抗氧化剂“升态口服液” ,对照组服用安慰剂。分别测试受试对象实验前、后的乳酸无氧阈功率、心率恢复和血液生化指标。结果 :服用“升态口服液”后实验组的乳酸无氧阈功率明显提高 (P <0 0 1) ,而对照组则无显著变化。服用口服液 2周和 3周后实验组血清BUN水平明显低于对照组 (P <0 0 5 ) ;两组间及其组内不同时间的血清T水平无显著变化。对照组的CK活性实验后比实验前明显升高 (P <0 0 5 ) ;而实验组则无明显差异。实验组的LDH活性实验后明显低于实验前 (P <0 0 5 ) ,血清MDA浓度实验后明显低于实验前 (P <0 0 5 ) ,同时显著低于对照组 (P <0 0 5 )。对照组的血清SOD水平 ,实验后明显低于实验前 (P <0 0 5 ) ,而实验组无明显变化。提示服用“升态口服液”可降低运动后血清CK水平 ,促进中长跑运动员有氧能力提高 ,有效清除运动中产生的自由基 ,具有一定的抗疲劳作用。     

Nontraumatic femur fracture in an oligomenorrheic athlete.

Exercise-associated amenorrhea is the cessation of menses in a woman following onset of training or an increase in training intensity. Its physiologic basis is characterized by consistently low levels of gonadotropin and ovarian hormones, but the underlying cause of this phenomenon is unknown. Although osteopenia has been described in amenorrheic women athletes, it has been primarily a laboratory diagnosis. Several recent studies have described a significantly lower bone mineral density (BMD) in the lumbar spine of amenorrheic athletes. Marcus et al. also reported an increased number of metatarsal and tibial stress fractures in a group of amenorrheic women. We report here the first case of a nontraumatic femur fracture in an amenorrheic athlete. A 32-yr-old white female, with four prior fibular stress fractures, suffered a left femoral shaft fracture during the 13th mile of a half-marathon. The fracture was successfully internally fixed. Biochemical studies showed no metabolic abnormality. Bone mineral density of the lumbar spine, femoral neck, tibia, and fibula were below the mean for both eumenorrheic and amenorrheic female athletes. Exercise-associated amenorrhea is a medical problem that may have serious implications for both competitive and high-intensity recreational female athletes.     

The effect of amenorrhea on calcaneal bone density and total bone turnover in runners.

To examine in athletes the effect of long-term amenorrhea on the skeleton, measurements of calcaneal density and whole body retention of 99mTc-imidodiphosphate were made in 42 women who could be allocated to one of 3 groups defined by their level of physical activity and by menstrual status. There was no difference in bone density between eumenorrheic normoactive females and either eumenorrheic or amenorrheic athletes. However, calcaneal density was significantly greater for each group than for previously measured sedentary controls. Total body bone turnover was greater in both eumenorrheic and amenorrheic athletes than in eumenorrheic normoactive women. Sustained, intense physical activity does not significantly increase calcaneal bone density over and above the increase associated with normal levels of activity. This is despite a significant increase in the rate of total body bone mineral turnover.     

Bone mineral content and menstrual regularity in female runners

The relationship between bone mineral content and menstrual regularity in 10 amenorrheic runners (0-3 menses during the past year), 12 runners with regular menstrual cycles (10-12 menses during the past year), and 15 non-athletic women with regular menstrual cycles was investigated. Comparisons of the two groups of runners indicated no significant differences in body fatness, average weekly running distance, or average daily intake of calcium (Ca), phosphorus (P), and Ca/P ratios. Mean bone mineral content for the three groups, measured by photon absorptiometry, was 0.508, 0.529, and 0.544 g X cm-2, respectively, at 3 cm distal radius, and 0.707, 0.700, and 0.707 g X cm-2, respectively, at one-third distal radius, indicating no significant differences among the groups (P less than 0.05). However, a significant relationship (r = 0.77) was noted between bone mineral content and body fatness only in the amenorrheic runners. Within the amenorrheic population, the five thinnest runners had significantly lower mean bone mineral content values at 3 cm distal radius (0.457 g X cm-2) than the five runners with higher relative body fatness (0.559 g X cm-2). We conclude, therefore, that amenorrhea, independent of body composition, was not related to reduced bone mineral content in female runners. However, the combination of excessive thinness and amenorrhea may, in fact, predispose female athletes to reduced bone mass.     

Cortisol levels during prolonged exercise: the influence of menstrual phase and menstrual status.

The purpose of this study was to determine the influence of menstrual phase and menstrual status on the cortisol response during 90 minutes of treadmill running at 60% VO2max. Eight eumenhorrheic athletes were tested in the early follicular (EF) (day 3-5), late follicular (LF) (day 13-15) and mid-luteal (ML) (day 22-24) phases. Six amenorrheic athletes were tested on two separate occasions. The resting cortisol levels were similar in each menstrual phase and overall a decreasing pattern of cortisol response to exercise was observed in all menstrual phases (P greater than .05). The amenorrheic athletes had a significantly greater (P less than .01) pattern of cortisol response than was observed in eumenorrheic athletes. The net increment in cortisol levels during exercise were distinctly greater (P less than .01) in amenorrheic than eumenorrheic athletes (amenorrheic: 413.8 +/- 113.1, eumenorrheic: EF: -482.8 +/- 88.3, LF: -311.8 +/- 102.1, ML: -386.3 +/- 146.2 nmol.l-1). In conclusion the cortisol levels are independent of menstrual phase. Also a larger cortisol increment is observed in amenorrheic athletes in response to prolonged submaximal exercise. The elevated cortisol levels in amenorrheics at rest and throughout exercise provides further evidence that disturbances in the hypothalamic-pituitary-adrenal function are associated with exercise-induced amenorrhea, although the site(s) of physiological disturbance have not been identified.     

Factors affecting bone loss in female endurance athletes: a two-year follow-up study

BACKGROUND: Low bone mass leading to stress fractures is a well-known and yet unsolved problem among female athletes. PURPOSE: To quantify the rate of bone loss in healthy female athletes and investigate the effects of estrogen and vitamin K supplementation on bone loss. STUDY DESIGN: Prospective cohort study. METHODS: We classified 115 female endurance athletes into amenorrheic, eumenorrheic, or estrogen-supplemented groups and randomized them to receive either placebo or vitamin K(1). The bone mineral densities of the subjects' femoral neck and lumbar spine were measured at baseline and after 2 years. RESULTS: Bone mineral density in the lumbar spine remained constant, but bone density in the femoral neck had decreased significantly after 2 years in all three subgroups. The decrease was higher in amenorrheic (-6.5% +/- 4.0%) than in eumenorrheic (-3.2% +/- 4.1%) and estrogen-supplemented athletes (-3.9% +/- 3.1%). Supplementation with vitamin K did not affect the rate of bone loss. CONCLUSIONS: The rate of bone loss in all three subgroups of female athletes was unexpectedly high; neither estrogen nor vitamin K supplementation prevented bone loss. Clinical Relevance: High-intensity training maintained over several years must be regarded in women as a risk factor for osteoporosis, and protocols for optimal treatment should be developed.     

The strength of weight‐bearing bones is similar in amenorrheic and eumenorrheic elite long‐distance runners

Regular intense endurance exercise can lead to amenorrhea with possible adverse consequences for bone health. We compared whole body and regional bone strength and skeletal muscle characteristics between amenorrheic (AA : n = 14) and eumenorrheic (EA : n = 15) elite adult female long‐distance runners and nonathletic controls (C: n = 15). Participants completed 3‐day food diaries, dual‐energy X‐ray absorptiometry (DXA ), magnetic resonance imaging (MRI ), peripheral quantitative computed tomography (pQCT ), and isometric maximal voluntary knee extension contraction (MVC ). Both athlete groups had a higher caloric intake than controls, with no significant difference between athlete groups. DXA revealed lower bone mineral density (BMD ) at the trunk, rib, pelvis, and lumbar spine in the AA than EA and C. pQCT showed greater bone size in the radius and tibia in EA and AA than C. The radius and tibia of AA had a larger endocortical circumference than C. Tibia bone mass and moments of inertia (Ix and Iy) were greater in AA and EA than C, whereas in the radius, only the proximal Iy was larger in EA than C. Knee extensor MVC did not differ significantly between groups. Amenorrheic adult female elite long‐distance runners had lower BMD in the trunk, lumbar spine, ribs, and pelvis than eumenorrheic athletes and controls. The radius and tibia bone size and strength indicators were similar in amenorrheic and eumenorrheic athletes, suggesting that long bones of the limbs differ in their response to amenorrhea from bones in the trunk.     

The effect of oral contraceptives on bone mass and stress fractures in female runners

PURPOSE: To determine the effect of oral contraceptives (OC) on bone mass and stress fracture incidence in young female distance runners. METHODS: One hundred fifty competitive female runners ages 18-26 yr were randomly assigned to OC (30 microg of ethinyl estradiol and 0.3 mg of norgestrel) or control (no intervention) for 2 yr. Bone mineral density (BMD) and content (BMC) were measured yearly by dual x-ray absorptiometry. Stress fractures were confirmed by x-ray, magnetic resonance imaging, or bone scan. RESULTS: Randomization to OC was unrelated to changes in BMD or BMC in oligo/amenorrheic (N=50) or eumenorrheic runners (N=100). However, treatment-received analyses (which considered actual OC use) showed that oligo/amenorrheic runners who used OC gained about 1% per year in spine BMD (P<0.005) and whole-body BMC (P<0.005), amounts similar to those for runners who regained periods spontaneously and significantly greater than those for runners who remained oligo/amenorrheic (P<0.05). Dietary calcium intake and weight gain independently predicted bone mass gains in oligo/amenorrheic runners. Randomization to OC was not significantly related to stress fracture incidence, but the direction of the effect was protective in both menstrual groups (hazard ratio [95% CI]: 0.57 [0.18, 1.83]), and the effect became stronger in treatment-received analyses. The trial's statistical power was reduced by higher-than-anticipated noncompliance. CONCLUSION: OC may reduce the risk for stress fractures in female runners, but our data are inconclusive. Oligo/amenorrheic athletes with low bone mass should be advised to increase dietary calcium and take steps to resume normal menses, including weight gain; they may benefit from OC, but the evidence is inconclusive.     

Trabecular bone density and menstrual function in women runners

Osteoporosis results in decreased bone mineral mass and reduced trabecular bone density. Although its etiology remains unknown, studies have revealed differential changes in the bone mineral densities of postmenopausal women, anorexic women, and amenorrheic female athletes. Correlations have also been made between estrogen deficiency and osteoporosis in both premenopausal and postmenopausal women. In order to examine the possibility of osteopenia, a group of 36 female runners between the ages of 15 and 44 years were evaluated for bone mineral density, menstrual function, and dietary habits. Serum calcium, phosphorus, and parathyroid hormone (PTH) levels were also determined for each participant, as were complete blood counts. Using dual photon absorptiometry, all participants underwent a 20 minute scan of the lumbar spine with specificity to the L1-14 vertebrae. The 36 subjects included 19 oligomenorrheic and 17 eumenorrheic women. Results of bone density analyses revealed that the oligomenorrheic runners had significantly lower calibrated bone mineral density (CBMD) than their eumenorrheic counterparts (P less than or equal to 0.01). Likewise, the PTH levels of the oligomenorrheic runners were also significantly lower (P less than or equal to 0.01). Analysis of dietary logs revealed no significant differences between the dietary habits, the calcium intake, or the caloric intake of the two groups. The data from this study indicate that there is a relationship between reduced serum PTH levels and the oligomenorrheic state. The loss of the protective effect of estrogen in the oligomenorrheic runners possibly contributed to their reduced bone mineral densities and could be a contributing factor in osteopenia.     

Diet, hormonal, and metabolic factors affecting bone mineral density in adolescent amenorrheic and eumenorrheic female runners.

Seven adolescent female runners with secondary amenorrhea and six adolescent eumenorrheic female runners received dietary supplements of 1200 mg calcium carbonate and 400 IU vitamin D/d for 12 months. Bone mineral density (BMD) of the axial skeleton was measured by dual photon densitometry at the beginning and end of the 12 month period. Plasma estradiol and ionized calcium concentration were also determined. Bone mineral density decreased in two of the amenorrheic subjects, with the lowest estradiol values concurrent with the severest training regimen and highest calcium intake. There was a significant decrease in plasma estradiol concentration in the amenorrheic runners (p less than 0.05). Plasma ionized calcium and estradiol explained 99% of the variation in BMD (r2 = 0.999). A significant inverse relationship between plasma estradiol and miles run/week was observed (r2 = -0.748). Adolescent female runners who train extensively and have low plasma estradiol levels may be adversely affecting BMD despite supplemental calcium and vitamin D intake.