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1.
Abstract

The purpose of this study was to investigate the effect of melatonin administration on muscle glycogen concentration during recovery after exhaustive swimming exercise in sedentary and trained rats. Male Wistar rats were assigned to one of four groups: sedentary control (C), sedentary melatonin-injected (M), exercise-trained (T), and trained and melatonin-injected (MT) groups. Exercise-trained groups were subjected to six weeks of swimming exercise. All rats completed an exhaustive swimming exercise. Two daily subcutaneous injections of melatonin at a dose of 3 mg·kg?1 were given to the rats in the M and MT groups immediately after the exhaustive exercise. Plasma melatonin, glucose and lactate concentrations, and glycogen concentrations of the soleus and epitrochlearis muscle tissues were measured after exhaustive exercise. Plasma lactate concentration was significantly lower in the T and MT groups than in the C group. Plasma melatonin concentration was higher in the supplemented groups than in the C group. Plasma glucose concentration was significantly higher in the T and MT groups than in the C group. Both epitrochlearis and soleus muscle glycogen concentrations were higher in the trained groups than in the C group. In conclusion, although exercise training results in improvement in muscle glycogen, exogenous melatonin administration after exhaustive exercise did not restore the glycogen concentrations in fast- or slow-twitch muscle tissues.  相似文献   

2.
目的:探讨过度训练对大鼠胃肠吸收、糖贮备的影响,以及四君子汤结合补糖对改善胃肠功能和提高机体糖贮备的效果。方法:95只健康的Wistar雄性大鼠,随机分为五组。所有运动组进行6周的递增负荷游泳运动。测定D-木糖水平、胃泌素、胃动素、肌糖原、肝糖原、血糖、睾酮、皮质酮等指标。结果:经过6周递增负荷游泳训练,综合评定运动对照组大鼠达到过度训练状态。健脾补糖运动组与运动对照组相比,D-木糖和肌糖原差异具高度显著性。结论:四君子汤结合补糖能够在增强胃肠功能的基础上,提高机体的糖贮备,防止递增负荷游泳大鼠过度训练和脾虚的发生。  相似文献   

3.
目的:以去卵巢大鼠为研究对象,通过动物实验观察不同负重强度游泳运动对去势大鼠骨密度、骨矿物质含量及骨生物力学指标的变化,以探讨运动对骨质疏松症的治疗机制。方法:取10月龄雌性SD大鼠50只,随机分为A假手术安静组(正常对照组)、B模型安静组(实验对照组)、C低强度运动组、D中强度运动组、E高强度运动组,每组10只。除假手术组外,其余各组大鼠均行双侧卵巢切除术,假手术组按相同手术方法操作,但不切除卵巢。术后第10周分别给予游泳训练共12周。观察12周后不同负荷强度运动对各组大鼠右侧股骨骨密度及骨矿物质含量的变化,并取左侧股骨,进行骨生物力学指标检测。结果:游泳运动组大鼠股骨骨密度显著高于模型组(P<0.05),与假手术组比较,差异无统计学意义(P>0.05)。中强度运动组最大应力、断裂应力均明显优于模型组;各组最大伸长无显著差异。结论:适宜强度的游泳运动能明显抑制去势大鼠股骨骨密度及骨钙矿物质含量的降低及对大鼠的骨生物力学指标有良性调整作用。  相似文献   

4.
目的探索机体运动后糖原合成激素环境的变化以及补糖和补刺五加的干预效应,为补糖和刺五加促进运动后肌糖原恢复提供理论依据。方法 128只SD大鼠进行1周游泳训练,同时分别补充刺五加皂甙[500 mg/(kg.d)]、葡萄糖[6 g/(kg.d)]或生理盐水。随后进行糖原消耗运动,并于运动前后的不同时间点(运动前、运动后即刻、后4 h、后12 h)提取样本,测定血清胰岛素(insulin,INS)、胰高血糖素(glucagon,GL)水平和胰岛素受体-1(insu-lin receptor-1,IR-1)蛋白量。结果①补糖可以明显升高运动后大鼠的INS(U/mL)水平(24.50±2.46 vs19.15±1.56),同时补充刺五加有协同效应(24.59±3.88 vs19.15±1.56),而且这种效应一直持续至运动后12 h(29.67±3.26 vs 22.86±2.32)。②大鼠运动后GL(ng/L)水平明显升高(367.86±18.54 vs 221.76±22.28),运动后补充刺五加明显降低GL水平(328.62±20.10vs367.86±18.54)。③补糖对IR-1的蛋白量没有明显影响,而补充刺五加明显上调各时间点IR-1的蛋白量。结论补糖可以升高运动后INS水平,但是对IR-1蛋白含量的影响较小;补药对INS的影响较小,但升高了IR的蛋白含量。补药和补糖都降低了运动后血清GL的水平,两者同时补充的效果更好。  相似文献   

5.
[目的]：研究运动预适应对过度训练大鼠心肌缺血缺氧形态影响及血清MDA.[方法]：将鼠随机分为安静对照组、一般训练组、过度训练组、运动预适应组.安静对照组常规饲氧,不加干预;一般训练组第1-2w常规饲养,第3-4w进行无负重游泳运动,每次游泳1h/d,每周游泳6天.过度训练组第1-2w常规饲养,第3-4w每天进行一次尾部负重3％体重的负荷进行力竭性游泳,每周游泳6天.运动预适应组第1-2W大鼠每天尾部负重3％体重负荷进行间歇性游泳运动一次,每天游泳15 min,休息5 min,重复3次,6 d/周,周日休息,第3-4周运动与过度训练组的第3-4周训练一致.训练结束后取材,进行常规HE染色和HBEP染色并摄片,测血清MDA.[结果]：HE染色,过度训练组肌纤维排列紊乱,部分肌纤维界限模糊.运动预适应组肌纤维轮廓较清楚.HBEP染色过度训练组有若干片状的红色缺血缺氧部位;运动预适应组心肌缺血缺氧改变程度比过度训练组明显减轻.运动各组大鼠血清MDA均高于安静对照组;过度训练组高于一般训练组和运动预适应组.[结论]：运动预适应可以降低过度训练大鼠血清MDA的含量,对心肌缺血缺氧性损伤产生保护作用.  相似文献   

6.
Abstract

The purpose of this study was to determine the recovery rate of football skill performance following resistance exercise of moderate or high intensity. Ten elite football players participated in three different trials: control, low-intensity resistance exercise (4 sets, 8–10 repetitions/set, 65–70% 1 repetition maximum [1RM]) and high-intensity resistance exercise (4 sets, 4–6 repetitions/set, 85–90% 1RM) in a counterbalanced manner. In each experimental condition, participants were evaluated pre, post, and at 24, 48, 72 h post exercise time points. Football skill performance was assessed through the Loughborough Soccer Passing Test, long passing, dribbling, shooting and heading. Delayed onset muscle soreness, knee joint range of motion, and muscle strength (1RM) in squat were considered as muscle damage markers. Blood samples analysed for creatine kinase activity, C-reactive protein, and leukocyte count. Passing and shooting performance declined (P < 0.05) post-exercise following resistance exercise. Strength declined post-exercise following high-intensity resistance exercise. Both trials induced only a mild muscle damage and inflammatory response in an intensity-dependent manner. These results indicate that football skill performance is minimally affected by acute resistance exercise independent of intensity suggesting that elite players may be able to participate in a football practice or match after only 24 h following a strength training session.  相似文献   

7.
人参皂甙Rgl对大鼠运动过程中血糖及相关调节激素的影响   总被引：3，自引：1，他引：2  
研究人参皂甙Rgl对大鼠游泳过程中血糖和相关的血糖调节激素的血浓度变化的影响,为阐明其抗疲劳机制提供实验依据。连续两天给大鼠腹腔注射人参皂甙Rgl后,测定其力竭游泳时间、不同游泳时间后血糖、血胰岛素和血胰高血糖素浓度。人参皂甙Rgl给药组力竭游泳时间长于对照组;游泳过程中,给药组大鼠血糖浓度下降较慢,血胰岛素和血胰高血糖素浓度变化幅度较小。人参皂甙Rgl对游泳大鼠具有减缓血糖下降,预防运动性低血糖发生的作用,这种作用可能是由于相关血糖调节激素的分泌或活性变化引起。  相似文献   

8.
Abstract

The aim of the present study was to describe the frequency, duration, and nature of repeated high-intensity exercise in Super 14 rugby union. Time–motion analysis was used during seven competition matches over the 2008 and 2009 Super 14 seasons; five players from each of four positional groups (front row forwards, back row forwards, inside backs, and outside backs) were assessed (20 players in total). A repeated high-intensity exercise bout was considered to involve three or more sprints, and/or tackles and/or scrum/ruck/maul activities within 21 s during the same passage of play. The range of repeated high-intensity exercise bouts for each group in a match was as follows: 11–18 for front row forwards, 11–21 for back row forwards, 13–18 for inside backs, and 2–11 for outside backs. The durations of the most intense repeated high-intensity exercise bouts for each position ranged from 53 s to 165 s and the minimum recovery periods between repeated high-intensity exercise bouts ranged from 25 s for the back row forwards to 64 s for the front row forwards. The present results show that repeated high-intensity exercise bouts vary in duration and activities relative to position but all players in a game will average at least 10 changes in activity in the most demanding bouts and complete at least one tackle and two sprints. The most intense periods of activity are likely to last as long as 120 s and as little as 25 s recovery may separate consecutive repeated high-intensity exercise bouts. The present findings can be used by coaches to prepare their players for the most demanding passages of play likely to be experienced in elite rugby union.  相似文献   

9.
不同训练强度对间歇性缺氧大鼠骨骼肌NO和NOS的影响   总被引：6，自引：0，他引：6  
利用低氧舱技术模拟“高住低练”环境,观察间歇性缺氧条件和两种不同运动训练强度对骨骼肌NO和NOS的共同作用效应。SD雄性大鼠50只,随机分为6组:(1)常氧对照组(NC),(2)常氧低强度运动组(NEL),(3)常氧高强度运动组(NEH),(4)低氧对照组(HC),(5)低氧低强度运动组(HEL),(6)低氧高强度运动组(HEH)。低氧组每日20时至次日8时置于低氧舱中,其余时间置于常氧环境下。低氧舱氧浓度控制在14.7%,相当于海拔高度大约2800米。运动组每天在常氧环境中进行30分钟跑台训练,速度定为26.8米/分钟,低强度运动组坡度0度,高强度运动组坡度15度。9周后各组大鼠于安静状态进行宰杀,取股四头肌,匀浆进行NO含量和NOS活性检测。结果显示:常氧高强度运动组股四头肌NO水平与常氧对照组相比呈升高趋势并接近显著性水平(p=0.052)。低氧低运动强度组NO显著高于其他组,NOS变化组间比较均未达显著性水平。说明常氧条件下,高强度运动强度才能使NO释放增加。而在间歇性缺氧条件下,较低强度运动即可使NO释放明显增加。提示间歇性缺氧条件可使引起NO释放的运动强度阈值下降。  相似文献   

10.
Repeated high-intensity exercise in professional rugby union   总被引：1，自引：1，他引：0  
The aim of the present study was to describe the frequency, duration, and nature of repeated high-intensity exercise in Super 14 rugby union. Time-motion analysis was used during seven competition matches over the 2008 and 2009 Super 14 seasons; five players from each of four positional groups (front row forwards, back row forwards, inside backs, and outside backs) were assessed (20 players in total). A repeated high-intensity exercise bout was considered to involve three or more sprints, and/or tackles and/or scrum/ruck/maul activities within 21 s during the same passage of play. The range of repeated high-intensity exercise bouts for each group in a match was as follows: 11-18 for front row forwards, 11-21 for back row forwards, 13-18 for inside backs, and 2-11 for outside backs. The durations of the most intense repeated high-intensity exercise bouts for each position ranged from 53 s to 165 s and the minimum recovery periods between repeated high-intensity exercise bouts ranged from 25 s for the back row forwards to 64 s for the front row forwards. The present results show that repeated high-intensity exercise bouts vary in duration and activities relative to position but all players in a game will average at least 10 changes in activity in the most demanding bouts and complete at least one tackle and two sprints. The most intense periods of activity are likely to last as long as 120 s and as little as 25 s recovery may separate consecutive repeated high-intensity exercise bouts. The present findings can be used by coaches to prepare their players for the most demanding passages of play likely to be experienced in elite rugby union.  相似文献   

11.
唐晖  谢敏豪  姚绩伟  宋刚 《体育科学》2007,27(10):69-74
目的:验证骨骼肌白细胞介素6(interleukin6,IL-6)基因转录的增加可能与c-Jun氨基末端激酶(c-Jun NH2-terminal kinases,JNK)信号通道的激活有关,并且探讨运动前肌糖原含量是否影响收缩骨骼肌JNK信号通道的激活。方法:大鼠先进行糖原消耗运动,在恢复期24h内采取不同的膳食干预手段,使大鼠在下一次定量运动前骨骼肌肌糖原含量不同。结果:运动时,血浆IL-6浓度、骨骼肌IL-6mRNA及核磷酸化JNK含量均显著上升,运动后恢复期降低;在相同时间点,低糖原组血浆IL-6浓度及骨骼肌IL-6 mRNA均显著高于正常糖原组;在相同时间点,核磷酸化JNK含量在低糖原组与高糖原组之间没有显著性差异。结论:收缩骨骼肌中,IL-6基因转录可能与低糖原含量及JNK信号通道的激活有关,然而,低糖原促进的IL-6基因转录可能不是通过激活JNK信号通道。  相似文献   

12.
The aim of the current study was to establish which indicators of mobility are associated with successful wheelchair rugby performance and determine whether these indicators differed across classification. Data were collected from 11 international teams during 30 matches (353 match observations) using a radio-frequency-based, indoor tracking system across two tournaments. Players (n = 111) were first grouped by team rank as determined by their International Wheelchair Rugby Federation (IWRF) world ranking (LOW, MID, HIGH) and then into one of four groups based on their IWRF classification: Group I (0.5), Group II (1.0–1.5), Group III (2.0–2.5) and Group IV (3.0–3.5). The volume of activity (relative distance and mean speed), peak speed and time spent within classification-specific arbitrary speed zones were calculated for each individual. Although no differences were identified in the volume of activity, playing time was significantly reduced in LOW (34:51 ± 8:35) compared to MID (48:54 ± 0:51) and HIGH (45:38 ± 9:53), which was further supported by the greater number of substitutions performed by LOW. HIGH achieved greater peak speeds (3.55 ± 0.40 m · sˉ1) than LOW (3.27 ± 0.42 m · sˉ1) and MID (3.45 ± 0.41 m · sˉ1). Peak speed was further shown to be classification-dependent (P ≤ 0.005), whereby HIGH Groups III and IV players achieved greater peak speeds than LOW and MID. The time spent performing high-intensity activities was also greater in HIGH compared to LOW and MID, whilst further influenced by classification (P ≤ 0.0005). To conclude, peak speed and the ability to perform a greater number of high-intensity activities were associated with successful performance in wheelchair rugby.  相似文献   

13.
The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test-retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h(-1) was increased by 1.2 km · h(-1) every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO(2max) (v-VO(2max)). Peak running velocity in Carminatti's test was strongly correlated with v-VO(2max) (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = -0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.  相似文献   

14.
Abstract

Throughout adolescence, swimmers begin to carry out demanding endurance and high-intensity training sets, the effect of which on redox status is largely unknown. The aim of the present study was to investigate the effects of 2000-m continuous swimming and 6 × 50-m maximal swimming on the redox status of adolescent swimmers. Fifteen male and 15 female swimmers, aged 14–18 years, provided blood samples before, immediately after, 1 h after, and 24 h after each exercise for the determination of redox status parameters. Oxidative damage was short-lived and manifest as increases in 8-hydroxy-2?-deoxyguanosine (8-OHdG) 1 h after high-intensity exercise (39%, P < 0.001) and in malondialdehyde immediately after both exercises (65%, P < 0.001). Alterations in antioxidant parameters were sustained during recovery: reduced glutathione decreased 24 h post-exercise (11%, P = 0.001), uric acid increased gradually after high-intensity exercise (29%, P < 0.001) and bilirubin peaked 24 h post-exercise (29%, P < 0.001). Males had higher 8-OHdG (49%, P = 0.001) and uric acid (29%, P < 0.001) concentrations than females. However, females showed higher values of malondialdehyde than males immediately post-exercise (30%, P = 0.039), despite lower pre-exercise values. In conclusion, both endurance and high-intensity exercise perturbed the redox balance without inducing prolonged oxidative damage in trained adolescent male and female swimmers. These swimming training trials were not found to be detrimental to the redox homeostasis of adolescents.  相似文献   

15.
Present study examined the effects of conjugated linoleic acid (CLA) supplementation on glycogen resynthesis in exercised human skeletal muscle. Twelve male participants completed a cross-over trial with CLA (3.8 g/day for 8 week) or placebo supplements by separation of 8 weeks. CLA is a mixture of trans-10 cis-12 and cis-9 trans-11 isomers (50:50). On experiment day, all participants performed 60-min cycling exercise at 75% VO2 max, then consumed a carbohydrate meal immediately after exercise and recovered for 3 h. Biopsied muscle samples from vastus lateralis were obtained immediately (0 h) and 3 h following exercise. Simultaneously, blood and gaseous samples were collected for every 30 min during 3-h recovery. Results showed significantly increased muscle glycogen content with CLA after a single bout of exercise (P < 0.05). Muscle glucose transporter type 4 expression was significantly elevated immediately after exercise, and this elevation was continued until 3 h after exercise in CLA trial. However, P-Akt/Akt ratio was not significantly altered, while glucose tolerance was impaired with CLA. Gaseous exchange data showed no beneficial effect of CLA on fat oxidation, instead lower non-esterified fatty acid and glycerol levels were found at 0 h. Our findings conclude that CLA supplementation can enhance the glycogen resynthesis rate in exercised human skeletal muscle.  相似文献   

16.
Abstract

An investigation was conducted to determine the effects of fatiguing exercise upon the Achilles tendon reflex. Eleven subjects performed one of four exercise tasks on each of four separate days. The exercise conditions involved low-intensity isometric, high-intensity isometric, low-intensity isotonic or high-intensity isotonic exercise. The low-intensity tasks required a 25% MVC load, while the high-intensity conditions required a 50% MVC load. Results showed that low-intensity isometric exercise reduced reflex force, as well as the time needed to reach peak force, while high-intensity exercise produced an enhancement of reflex force. Half-relaxation time was faster after subjects executed low-intensity isometric exercise, but generally somewhat prolonged following high-intensity isometric exercise. Thus, the Achilles tendon reflex may be either enhanced or depressed depending upon the type and intensity of exercise performed.  相似文献   

17.
The aim of this study was to compare the effect of low-load resistance exercise (LLRE) with continuous and intermittent blood flow restriction (BFR) on the creatine kinase (CK), lactate dehydrogenase (LDH), protein carbonyl (PC), thiobarbituric acid-reactive substance (TBARS) and uric acid (UA) levels in military men. The study included 10 recreationally trained men aged 19 ± 0.82 years who underwent the following experimental protocols in random order on separate days (72–96 h): 4 LLRE sessions at a 20% 1RM (one-repetition maximum [1RM]) with continuous BFR (LLRE + CBFR); 4 LLRE sessions at 20% 1RM with intermittent BFR (LLRE + IBFR) and 4 high-intensity resistance exercise (HIRE) sessions at 80% 1RM. The CK and LDH (markers of muscle damage) levels were measured before exercise (BE), 24 h post-exercise and 48 h post-exercise, and the PC, TBARS and UA (markers of oxidative stress) levels were measured BE and immediately after each exercise session. There was a significant increase in CK in the HIRE 24 post-exercise samples compared with the LLRE + CBFR and LLRE + IBFR (P = 0.035, P = 0.036, respectively), as well as between HIRE 48 post-exercise and LLRE + CBFR (P = 0.049). Additionally, there was a significant increase in CK in the LLRE + CBFR samples BE and immediately after each exercise (Δ = 21.9%) and in the HIRE samples BE and immediately after each exercise, BE and 24 post-exercise, and BE and 48 post-exercise (Δ values of 35%, 177.6%, and 177.6%, respectively). However, there were no significant changes in LDH, PC, TBARS, and UA between the protocols (P > 0.05). Therefore, a physical exercise session with continuous or intermittent BFR did not promote muscle damage; moreover, neither protocol seemed to affect the oxidative stress markers.  相似文献   

18.
目的：采用大鼠下坡跑运动损伤模型,研究离心力竭运动后不同时刻大鼠骨骼肌肌浆网Ca^2＋-ATP酶活性的变化,探讨离心力竭运动所致骨骼肌超微结构损伤机制,为科学运动训练及运动恢复提供实验和理论依据。方法：雄性SD大鼠60只随机分为6组（每组10只）：安静对照组、运动后即刻组、12h组、24h组、48h组和72h组,以速度16m/min,坡度-16°进行跑台运动,运动100min,休息5min,再运动100min,在不同时刻观察大鼠肱三头肌肌浆网Ca^2＋-ATP酶活性的变化。结果：运动后即刻肌浆网Ca^2＋-ATP酶活性与对照组相比显著下降（P〈0.01）,随后开始恢复,运动后24h接近对照组水平（P〉0.05）,运动后48h已完全恢复到对照组水平。结论：离心力竭运动后即刻大鼠肱三头肌肌浆网Ca^2＋-ATP酶活性显著下降,随后逐渐恢复,运动后24h明显恢复,至48h已完全恢复,肌浆网Ca^2＋-ATP酶活性的变化可以间接评定运动后骨骼肌的损伤。  相似文献   

19.
恢复能力的可训练性初探   总被引：1，自引：1，他引：0  
实践运动中恢复作为训练课的从属部分，成为进一步冲击新的体能极限的瓶颈。能否另辟蹊径？将恢复作为训练课的主导内容!方法：大鼠147只，游泳训练2周。按36h超量恢复区间连续在训练后即刻、休息36h取样。结果：①血乳酸、血糖、血尿酸纵向比较；恢复幅度在前5区间呈增加趋势；②肝醣元：训练即刻组前6区间逐步上升，6×36h达峰值。恢复组前5区间维持在较高水平；③肌糖元：训练即刻组前4区间逐步上升，4×36h达峰值。恢复组前5区间维持在较高水平。结论：在小周期训练中，机体的恢复能力具有可训练性。  相似文献   

20.
旱莲草提取物抗疲劳作用研究   总被引：8，自引：0，他引：8  
目的:研究旱莲草提取物的抗疲劳作用;方法:给药组以8 g·kg-1·d-1旱莲草煎液灌胃给药,1次/d.测定小鼠血清SOD、LA、LDH,血红蛋白,血糖和肝、肌糖原等指标.结果:旱莲草提取物使小鼠血清SOD和LDH的活性和Hb和肝、肌糖原含量升高,LA含量降低;结论:旱莲草提取物具有抗疲劳作用而提高机体的运动能力,可作为抗疲劳功能食品进行开发和研究.  相似文献   

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