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1.
为探讨临界功率(简称CP)评价人体有氧能力的可靠性,以本省9名自行车运动员为研究对象,用逐级递增负荷法测其最大吸氧量(简称VO2max),据4次力竭运动的负荷和对应的疲劳时间来推算CP的值.测定结果VO2max为4.542±0.272l/min,VO2max/kg为58.87±4.947ml/min/kg,,CP为281.380土19.882W,CP与VO2max相关显著(R＝0.7422,P<0.05),而CP与VO2max/kg的相关不显著.提示CP可以用来衡量人体的有氧能力,CP所代表的有氧能力与体重无关.  相似文献   

2.
1 研究对象从事运动训练6—8年的男性运动员20名,平均年龄为21±1.59岁,平均身高为178.5±19.2,平均体重为74.6±5.8公斤。 2 研究方法 2.1 运动负荷:采用两种负荷方式,一种是应用Wingate法进行30秒无氧功率运动(Anaerobic Power Exercise,简称APE);另一种负荷方式是在功率自行车进行递增负荷运动(Progressive Resistance exercise,简称PRE),其运动阻力为50、100、  相似文献   

3.
临界功率(CP):释义与应用   总被引：2，自引：0，他引：2  
探讨临界功率在运动训练中的生理表达、测评方法、作用机制以及与有氧耐力训练效应之间的关系等.研究发现:1)临界功率可以作为极限运动和高强度运动的有氧训练指标,可作为这一运动强度范围的下限;2)临界功率(CP)应该是高于乳酸阈(LT)这一指标,处于乳酸阈与最大耗氧量之间的一种运动强度,并且以临界功率水平运动,耗氧量将处于一种稳定状态,而在临界功率水平以上训练,其耗氧量将迅速达到最大值;3)全力运动测试作为一种对临界功率的测评方式,有较好的效度,但缺乏进一步的实验证据.而三参数模型是普遍认可的一种模型评价,如何将两者有效结合,可能成为更为有效的测评方式.  相似文献   

4.
优秀男子花剑运动员无氧代谢能力的特点   总被引：5，自引：0，他引：5  
目的:通过准确测定与评价个体优秀花剑运动员的无氧代谢能力,为其合理制定体能训练计划提供帮助。方法:以叶冲等4名优秀花剑运动员为研究对象,采用MONAK839E功率自行车,分别进行15s和30s最大用力持续运动的测试。测定最大功率(Pmax)、平均功率(AP)、功率下降速率(PD)、最大圈数(Cmax)、达到最大功率的时间(Pmax-time)、达到最大圈数的时间(Cmax-time)、心率(HR)、血乳酸(BLa)等指标。结论:男子花剑运动员需要较强的磷酸原代谢能力和迅速调动无氧糖酵解代谢供能的能力;而应用MONAK839E功率自行车,根据需要设计不同测试方式测定优秀花剑运动员的无氧代谢能力,可清楚诊断和分析花剑运动员的磷酸原代谢能力和糖酵解代谢能力,为运动员机能状态诊断和制定不同阶段的训练计划提供参考。  相似文献   

5.
Conconi等人最近指出:心率在渐增负荷中的转折点是较理想的推测有氧阈的指标。而我们认为:说它是无氧阈的推测指标则更为恰当些。为了验证我们的看法,我们对11名体质状况不同的受试者进行了测定。受试者在功率自行车上做渐增负荷运动。记录每分钟心率。每分钟采一血样以测定血乳酸含量。结果表明:当用功率(瓦)表示时,各变量间的相关系数如下:有氧阈与无氧阈r=0.92;有氧阈与心率转折点r=0.89;无氧阈与心率转折点r=0.97.有氧阈时的功率(166.4±52.6W)显著低于心率转折点时的功率(234.5±69.5W),而无氧阈时的功率(240.0±67.1W)与心率转折点无显著差异。另有16名受试者重复做两  相似文献   

6.
比较恒功率不同阻力下运动性疲劳的生理、生化特点,探寻恒功率不同阻力下运动性疲劳的发生和恢复规律.选取15名健康男生,用功率自行车进行5次300W恒功率运动测试,每次测试采用不同运动阻力,运动后即刻记录运动时间,测试心率、血压、血红蛋白(Hb)、血尿素(BU)以及血液肌酸激酶(CK),次日晨再次测试Hb、BU、CK.结果表明:在预定功率的恒功率运动中,阻力过低或过大都不利于延长运动时间,适宜的阻力才可以维持较长的运动时间;工作肌收缩频率增加易导致心率增加和血红蛋白损伤,工作肌收缩阻力增加易导致血压升高和BU、CK恢复减慢.  相似文献   

7.
对递增负荷运动中普通中学男生的心功能评价的研究   总被引：1，自引：0，他引：1  
采用超声心动图法研究普通中学男生在安静状态下和连续运动过程中的心功能变化情况。研究对象为普通中学男生 2 7名 ,平均年龄 13 7岁 ,平均身高 1 5 9± 0 0 7ｍ ,平均体重 4 5 2± 5 9ｋｇ ,平均体表面积 1 4 0± 0 16ｍ2 。应用国产ＣＴＳ - 16型超声诊断仪测定被试者在连续运动过程中的Ｍ型超声心动图。应用ＥＣＭ -Ⅲ型踏式心功量计加运动负荷。受试者平卧位 ,运动时间约 9ｍｉｎ。第一个 2ｍｉｎ功率为 12 0 0ｋｇ·ｍ/ｍｉｎ ;第二个 2ｍｉｎ功率为 4 0 0ｋｇ·ｍ/ｍｉｎ ;第三个 2ｋｇ·ｍ/ｍｉｎ功率为 90 0ｋｇ·ｍ/ｍｉｎ ;第四个 2ｍｉｎ功率为 12 0 0ｋｇ·ｍ/ｍｉｎ ,速度均为 6 0转 /ｍｉｎ ;最后 1ｍｉｎ以功率为 12 0 0ｋｇ·ｍ/ｍｉｎ做最大速度蹬车运动至力竭。运动过程中 ,探头固定于Ⅱｂ区同一点 ,连续探查 ,间隔约半分钟做一次记录。在逐级递增负荷运动中 ,被试者安静状态下和运动过程中的心功能均低于成年人 ,但高于同龄女生。在运动过程中 ,采用左室舒末内径 (Ｄｄ) ,左室缩末内径 (Ｄｓ) ,左室舒末容积 (ＥＤＶ) ,左室缩末容积 (ＥＳＶ) ,心搏量 (ＳＶ) ,心输出量 (ＣＯ) ,射血分数 (ＥＦ) ,短轴缩短率 (ＦＳ)等指标评价被试者的心功能。除ＣＯ外 ,在心率 (ＨＲ)超过180次  相似文献   

8.
方志军  李兵 《体育学刊》2012,(2):120-123
运用临界功率理论,结合龙舟项目运动员不同距离的供能特点,探索应用龙舟测功仪训练运动员体能的手段,确立了龙舟运动员P-t、D-t、D-P、P-D-1数学模型,找到不同距离临界功率训练的区间。研究表明:1)P-t模型成非线性,曲线底端接近临界功率点。2)D-t模型成线性,直线的斜率代表了临界功率值。3)D-P模型成非线性,临界功率(CP)值是这个双曲线函数的一支渐近线与功率(横轴)的交点。4)P-D-1模型成线性,截距代表了运动员的有氧工作能力,函数的斜率代表了运动员的无氧工作能力。  相似文献   

9.
检测高水平耐力运动员血浆儿茶酚胺阈、乳酸阈(T_(LA))通气阈(T_(E))之间的关系。6名自行车和6名越野跑运动员于两种测诚装置(跑台、功率自行车)执行渐增负荷运动测试。自行车运动员跑台和踏车运动时O_2max分别为64.6±1.0,63.5±0.4ml.kg。min~(-1),不存在明显差异。但跑台运动时T_(LA)和TE的运动负荷(%O_2max)较低。越野跑运动员测试结果相反,踏车运动时T_(LA)和T_(E)的运动负荷较低,踏车和跑台运动中T_(LA)和T_(E)的运动负荷分别为60.0±1.7和75.0土4.0%O_2max。测试中血浆儿茶酚胺的变化与T_(LA)变化趋势一致(r=0.974±0.0007)而与训练形式或训练状态无关。T_(E)与T_(LA)变化较高相关(r=0.86)但不如T_(LA)与血浆儿茶酚胺明显,推测在渐增负荷运动中,血浆儿茶酚胺变化与T_(LA)之间存在因果关系。  相似文献   

10.
金Yun 《体育科研》2003,24(1):68-68
研究背景 :以往的研究表明 ,在长时间运动训练 (超过 2小时 )的前、后都应该补充碳水化合物 ,而有许多研究发现 ,运动前 1小时补糖是无效的。因为研究的样本量小引起了相争的结果 ,所以要下结论是困难的。从运动前补糖的研究项目来看 ,关于自行车和跑步的研究较多。研究目标 :了解运动前葡萄糖的不同时间摄入对提高运动员长距离游泳的成绩的影响。研究设计 :实验室研究研究方法 :十名加拿大男性铁人三项运动员 (年龄 :2 9.5± 5.0岁 ;最大吸氧量 :4 8.8± 3 .2ｍｌ/ｋｇ/ｍｉｎ)分别在运动前 5分钟、运动前 3 5分钟或不摄入 10 %的葡萄糖溶…  相似文献   

11.
Time-to-exhaustion (TTE) trials are used in a laboratory setting to measure endurance performance. However, there is some concern with their ecological validity compared with time-trials (TT). Consequently, we aimed to compare cycling performance in TTE and TT where the duration of the trials was matched. Seventeen trained male cyclists completed three TTE trials at 80, 100 and 105% of maximal aerobic power (MAP). On a subsequent visit they performed three TT over the same duration as the TTE. Participants were blinded to elapsed time, power output, cadence and heart rate (HR). Average TTE was 865 ± 345 s, 165 ± 98 s and 117 ± 45 s for the 80, 100 and 105% trials respectively. Average power output was higher for TTE (294 ± 44 W) compared to TT (282 ± 43 W) at 80% MAP (P < 0.01), but not at 100 and 105% MAP (P > 0.05). There was no difference in cadence, HR, or RPE for any trial (P > 0.05). Critical power (CP) was also higher when derived from TTE compared to TT (P < 0.01). It is concluded that TTE results in a higher average power output compared to TT at 80% MAP. When determining CP, TTE rather than TT protocols appear superior.  相似文献   

12.
Abstract

It has been shown that the critical power (CP) in cycling estimated using a novel 3-min all-out protocol is reliable and closely matches the CP derived from conventional procedures. The purpose of this study was to assess the predictive validity of the all-out test CP estimate. We hypothesised that the all-out test CP would be significantly correlated with 16.1-km road time-trial (TT) performance and more strongly correlated with performance than the gas exchange threshold (GET), respiratory compensation point (RCP) and V?O2 max. Ten club-level male cyclists (mean±SD: age 33.8±8.2 y, body mass 73.8±4.3 kg, V?O2 max 60±4 ml·kg?1·min?1) performed a 10-mile road TT, a ramp incremental test to exhaustion, and two 3-min all-out tests, the first of which served as familiarisation. The 16.1-km TT performance (27.1±1.2 min) was significantly correlated with the CP (309±34 W; r=?0.83, P<0.01) and total work done during the all-out test (70.9±6.5 kJ; r=?0.86, P<0.01), the ramp incremental test peak power (433±30 W; r=?0.75, P<0.05) and the RCP (315±29 W; r=?0.68, P<0.05), but not with GET (151±32 W; r=?0.21) or the V?O2 max (4.41±0.25 L·min?1; r=?0.60). These data provide evidence for the predictive validity and practical performance relevance of the 3-min all-out test. The 3-min all-out test CP may represent a useful addition to the battery of tests employed by applied sport physiologists or coaches to track fitness and predict performance in atheletes.  相似文献   

13.
ABSTRACT

Purpose: To validate and compare a novel model based on the critical power (CP) concept that describes the entire domain of maximal mean power (MMP) data from cyclists.

Methods: An omni-domain power-duration (OmPD) model was derived whereby the rate of W? expenditure is bound by maximum sprint power and the power at prolonged durations declines from CP log-linearly. The three-parameter CP (3CP) and exponential (Exp) models were likewise extended with the log-linear decay function (Om3CP and OmExp). Each model bounds W? using a different nonconstant function, W?eff (effective W?). Models were fit to MMP data from nine cyclists who also completed four time-trials (TTs).

Results: The OmPD and Om3CP residuals (4 ± 1%) were smaller than the OmExp residuals (6 ± 2%; P < 0.001). W?eff predicted by the OmPD model was stable between 120–1,800 s, whereas it varied for the Om3CP and OmExp models. TT prediction errors were not different between models (7 ± 5%, 8 ± 5%, 7 ± 6%; P = 0.914).

Conclusion: The OmPD offers similar or superior goodness-of-fit and better theoretical properties compared to the other models, such that it best extends the CP concept to short-sprint and prolonged-endurance performance.  相似文献   

14.
Purpose: Critical power (CP) from the 3-min test was compared to the power outputs associated with thresholds determined from gas exchange parameters that have been used to demarcate the exercise-intensity domains including the respiratory compensation point (RCP), gas exchange threshold (GET), and ventilatory threshold (VT). Method: Twenty-eight participants performed an incremental-cycle ergometer test to exhaustion. The VT was determined from the relationship between the ventilatory equivalent for oxygen uptake (V˙E/V˙O2) versus V˙O2 and the GET was determined using the V-slope method (V˙CO2 vs. V˙O2). The RCP was identified from the V˙E-versus-V˙CO2 relationship. CP was the average power output during the last 30 s of the 3-min all-out test. Linear regression was used to determine the power outputs associated with the RCP, GET, and VT, as well as the V˙O2 associated with CP. Mean differences among the associated power outputs, percent V˙O2 peak, and percent peak power output for the GET, VT, RCP, and CP were analyzed using separate one-way repeated-measures analyses of variance. Results: There were no significant differences between CP (187 ± 47 W) and the power output associated with RCP (190 ± 49 W) or between the power outputs associated with GET (139 ± 37 W) and VT (145 ± 37 W). The power outputs associated with GET and VT, however, were significantly less than were those at CP and associated with RCP. Conclusions: These findings suggest CP and RCP demarcate the heavy from severe exercise-intensity domain and result from a different mechanism of fatigue than that of GET and VT, possibly hyperkalemia.  相似文献   

15.
Purpose: To determine the accuracy of critical power (CP) and W? (the curvature constant of the power-duration relationship) derived from self-paced time-trial (TT) prediction trials using mobile power meters to predict 16.1-km road cycling TT performance. This study also aimed to assess the agreement between functional threshold power (FTP) and CP.

Methods: Twelve competitive male cyclists completed an incremental test to exhaustion, a FTP test and 4–5 self-paced TT bouts on a stationary bike within the lab, and a 16.1 km road TT, using mobile power meters.

Results: CP and W? derived from the power-duration relationship closely predicted TT performance. The 16.1-km road TT completion time (26.7 ± 2.2 min) was not significantly different from and was significantly correlated with the predicted time-to-completion (27.5 ± 3.3 min, r = 0.89, P < 0.01). CP and FTP were not significantly different (275 ± 40 W vs. 278 ± 42 W, P > 0.05); however, the limits of agreement between CP and FTP were 30 to -36 W.

Discussion: The findings of this study indicate that CP and W? determined using mobile power meters during maximal, self-paced TT prediction trials can be used to accurately predict 16.1-km cycling performance, supporting the application of the CP and W? for performance prediction. However, the limits of agreement were too large to consider FTP and CP interchangeable.  相似文献   


16.
The varying results reported in response to β-alanine supplementation may be related to the duration and nature of the exercise protocol employed. We investigated the effects of β-alanine supplementation on a wide range of cycling performance tests in order to produce a clear concise set of criteria for its efficacy. Fourteen trained cyclists (Age?=?24.8?±?6.7?years; VO2max?=?65.4?±?10.2 mL·kg·min?1) participated in this placebo-controlled, double-blind study. Prior to supplementation, subjects completed two (familiarization and baseline) supramaximal cycling bouts until exhaustion (120% pre-supplementation VO2max) and two 1-, 4- and 10-km cycling time trial (TT). Subjects then supplemented orally for 4 weeks with 6.4?g/d placebo or β-alanine and repeated the battery of performance tests. Blood lactate was measured pre-exercise, post-exercise and 5 min post-exercise. β-alanine supplementation elicited significant increases in time to exhaustion (TTE) (17.6?±?11.5 s; p?=?0.013, effect compared with placebo) and was likely to be beneficial to 4-km TT performance time (?7.8?±?8.1 s; 94% likelihood), despite not being statistically different (p?=?0.060). Performance times in the 1- and 10-km TT were not affected by treatment. For the highly trained cyclists in the current study, β-alanine supplementation significantly extended supramaximal cycling TTE and may have provided a worthwhile improvement to 4-km TT performance. However, 1- and 10-km cycling TT performance appears to be unaffected by β-alanine supplementation.  相似文献   

17.
Abstract

The aim of this study was to determine the relative and absolute reliability of second lactate turnpoint using fixed and individual blood lactate method in competitive cyclists. Twenty-eight male, well-trained cyclists (30.2 ± 10.1 years, 72.0 ± 7.4 kg, 177.3 ± 4.7 cm) were recruited to participate in this study. Cyclists completed two incremental cycling tests to exhaustion over a period of 7 days to determine their peak power output, maximal oxygen uptake, maximal heart rate, maximal blood lactate concentration and two lactate turnpoint criteria. The fixed blood concentration criterion (3.5 mM) and an individual criterion were assessed by a lactate-power curve, considering power output, heart rate and oxygen uptake. The main finding of this study was that both lactate turnpoint criteria showed identical low within-subject variation for power output (2.8% coefficient of variation). High values for test–retest correlations ranging from r = 0.70 to r = 0.94 were found for all variables in both threshold criteria. In conclusion, the individual and fixed method to determine the second lactate turnpoint showed similar high absolute and relative reliability in competitive cyclists.  相似文献   

18.
The aim of this study was to compare the cycling performance of cyclists and triathletes. Each week for 3 weeks, and on different days, 25 highly trained male cyclists and 18 highly trained male triathletes performed: (1) an incremental exercise test on a cycle ergometer for the determination of peak oxygen consumption (VO2peak), peak power output and the first and second ventilatory thresholds, followed 15 min later by a sprint to volitional fatigue at 150% of peak power output; (2) a cycle to exhaustion test at the VO2peak power output; and (3) a 40-km cycle time-trial. There were no differences in VO2peak, peak power output, time to volitional fatigue at 150% of peak power output or time to exhaustion at VO2peak power output between the two groups. However, the cyclists had a significantly faster time to complete the 40-km time-trial (56:18 +/- 2:31 min:s; mean +/- s) than the triathletes (58:57 +/- 3:06 min:s; P < 0.01), which could be partially explained (r = 0.34-0.51; P < 0.05) by a significantly higher first (3.32 +/- 0.36 vs 3.08 +/- 0.36 l x min(-1)) and second ventilatory threshold (4.05 +/- 0.36 vs 3.81 +/- 0.29 l x min(-1); both P < 0.05) in the cyclists compared with the triathletes. In conclusion, cyclists may be able to perform better than triathletes in cycling time-trial events because they have higher first and second ventilatory thresholds.  相似文献   

19.
Objective: To quantify the effects of acute hypoxic exposure on exercise capacity and performance, which includes continuous and intermittent forms of exercise. Design: A systematic review was conducted with a three-level mixed effects meta-regression. The ratio of means method was used to evaluate main effects and moderators providing practical interpretations with percentage change. Data sources: A systemic search was performed using three databases (Google scholar, PubMed and SPORTDiscus). Eligibility criteria for selecting studies: Inclusion was restricted to investigations that assessed exercise performance (time trials (TTs), sprint and intermittent exercise tests) and capacity (time to exhaustion test, TTE) with acute hypoxic (<24?h) exposure and a normoxic comparator. Results: Eighty-two outcomes from 53 studies (N?=?798) were included in this review. The results show an overall reduction in exercise performance/capacity ?17.8?±?3.9% (95% CI ?22.8% to ?11.0%), which was significantly moderated by ?6.5?±?0.9% per 1000 m altitude elevation (95% CI ?8.2% to ?4.8%) and oxygen saturation (?2.0?±?0.4%; 95% CI ?2.9% to ?1.2%). TT (?16.2?±?4.3%; 95% CI ?22.9% to ?9%) and TTE (?44.5?±?6.9%; 95% CI ?51.3% to ?36.7%) elicited a negative effect, whilst indicating a quadratic relationship between hypoxic magnitude and both TTE and TT performance. Furthermore, exercise less than 2 min exhibited no ergolytic effect from acute hypoxia.

Summary/Conclusion: This review highlights the ergolytic effect of acute hypoxic exposure, which is curvilinear for TTE and TT performance with increasing hypoxic levels, but short duration intermittent and sprint exercise seem to be unaffected.  相似文献   

20.
This study tested the hypothesis that ischemic preconditioning (IPC) would increase critical power (CP) during a 3 minute all-out cycling test. Twelve males completed two 3 minute all-out cycling tests, in a crossover design, separated by 7 days. These tests were preceded by IPC (4 x 5 minute intervals at 220 mmHg bilateral leg occlusion) or SHAM treatment (4 x 5 minute intervals at 20 mmHg bilateral leg occlusion). CP was calculated as the mean power output during the final 30 s of the 3 minute test with W′ taken as the total work done above CP. Muscle oxygenation was measured throughout the exercise period. There was a 15.3 ± 0.3% decrease in muscle oxygenation (TSI; [Tissue saturation index]) during the IPC stimulus, relative to SHAM. CP was significantly increased (241 ± 65 W vs. 234 ± 67 W), whereas W′ (18.4 ± 3.8 vs 17.9 ± 3.7 kJ) and total work done (TWD) were not different (61.1 ± 12.7 vs 60.8 ± 12.7 kJ), between the IPC and SHAM trials. IPC enhanced CP during a 3 minute all-out cycling test without impacting W′ or TWD. The improved CP after IPC might contribute towards the effect of IPC on endurance performance.  相似文献   

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