两种无氧阈测试法在赛艇运动中应用的比较研究

采用两种不同的无氧阈测试方法(乳酸法和Conconi法)对赛艇运动员进行测试,并比较其结果的相关性。结果表明:其无氧阈血乳酸值无显著性差异,无氧阈心率存在显著性差异,心率之间的差异有可能是由最大乳酸稳定状态下的个体乳酸阈最大速度引起的,在赛艇训练中以Conconi测试的心率拐点作为无氧阈训练的评定指标更有利于运动员有氧耐力水平的提高。     

采用血乳酸个体无氧阈评价速滑运动员非冰期专项身体训练

本文运用联邦德国Kindermann教授的“个体无氧阈”概念的理论,采用递增负荷的方法,在我省优秀速滑运动员的非冰期身体训练中,用美国产YSI—23L血乳酸快速分析仪,进行血乳酸测试。同时,使用芬兰产POLARELECTRO心率遥测系统测定心率值,并绘制心率曲线图。从而得出非冰期专项身体训练中运动员的血乳酸“个体无氧阈”值,为速滑运动员陆地专项身体训练提供了重要的生理指标。     

最大乳酸稳定状态下足球运动员康科尼测试中个体无氧阈最大速度的选取及可靠性研究

研究目的 :1)应用场地康科尼测试方法寻找足球运动员个体无氧阈最大速度的可行性 ;2 )分析康氏测试心率拐点与乳酸阈拐点对应的个体无氧阈最大速度之间的关系 ;3)测定最大乳酸稳定状态 ( ML SS) ,验证康氏测试个体无氧阈最大速度的可靠性。结果证明 ,在康氏测试中 85 %受试者都出现心率拐点 ,完成距离最短者心率拐点偏左、中长者居中、最长者偏右 ,相对应的乳酸阈速度正好低于心率拐点速度一个等级 ,但该两种速度之间并未出现不规则变化差异 ,且高度相关。选取康氏测试心率拐点速度进行 2 4 min匀速运动受试者平均乳酸值显示最大乳酸稳定状态 ( ML SS) ,表明可用于个体无氧阈最大速度 ,但大于 180次 / m in的心率拐点速度即已超过本人的个体无氧阈最大速度     

对中国优秀女子赛艇运动员动态心率无氧阈的探讨

本文对18名中国优秀女子赛艇运动员在赛艇测功仪上用逐级间歇递增负荷法,进行了动态遥测心率与血乳酸无氧阈之间关系的测试研究。发现其负荷心率拐点的输出功率与血乳酸无氧阈的输出功率呈线性关系。     

青少年足球运动员在递增负荷运动中各生理指标的变化研究及应用

研究目的:分析青少年足球运动员在逐级递增负荷运动中各生理指标的变化,并探讨心率拐点在青少年运动员有氧能力评定中的应用的可能性,为优秀青少年运动员的科学选拔和科学训练提供可能的理论依据。研究对象与方法:U-15队的20名男子青少年足球运动员,测定最大摄氧量、心率、氧脉搏、通气量、呼吸商值;确定通气无氧阈、乳酸无氧阈、心率拐点。研究结果:本研究测得U-15男子足球运动员心肺功能各指标之间均具有显著相关性。受试者乳酸无氧阈、心率拐点的出现在时间上有高度的一致性。不同受试者个体乳酸阈、心率拐点、通气无氧阈出现的时间和所对应的运动强度有明显差异,随着最大有氧能力的增大向右漂移。Conconi心率拐点可以用来评定青少年运动员有氧能力。     

利用最大乳酸稳态测试判定赛艇运动员4 mmol/L乳酸阈与个体乳酸阈有效性的研究

目的:结合赛艇专项运动特点,利用Concept II赛艇测功仪对最大乳酸稳态(MLSS)测试进行改进,并根据MLSS测试判定赛艇运动员以4 mmol/L乳酸阈(AT4)和个体乳酸阈(IAT)指代无氧阈的有效性.方法:10名男子公开级赛艇运动员在Concept II赛艇测功仪上进行1次递增负荷测试和2～4次30 min恒定负荷测试,在相应的负荷间歇测定血乳酸.通过递增负荷测试获取AT4和IAT,并在恒定负荷测试中分别以AT4和IAT作为初试负荷,以2.5%IAT作为最小调整负荷,以运动中第10～30 min乳酸浓度上升<1 mmol/L作为判定标准获取MLSS.结果:1)AT4和MLSS发生时功率分别为342.4±18.8 W vs 312.5±16.0 W,二者差异非常显著(P<0.01)且相关较弱(r=0.607,P>0.05);AT4高估MLSS功率达9.7%,二功率相对差异范围为0%～15.4%;仅2人以AT4强度完成30 min恒定负荷测试,其中1人达到MLSS.2)IAT功率为314.4±19.9 W,略高于MLSS功率(P>0.05),二者相关非常显著(r=0.885,P<0.01);IAT比MLSS功率高0.6%,相对差异范围为-4.8%～5.3%;所有受试者均能以IAT强度完成30 min恒定负荷测试,其中7人以稳态乳酸完成,且有5人在IAT强度达到MLSS.结论:结合赛艇运动员专项特征的MLSS测试方案能提高测试的简便性和准确性;AT4显著地高估了赛艇运动员的无氧阈水平,而IAT可作为赛艇运动员无氧阈训练的有效负荷区间.     

CONCONI测试对足球运动员有氧能力评定的可行性研究

应用CONCONI测试方法寻找足球运动员个体无氧闲心率，验证采用CONCONI拐点心率评价足球运动员个体无氧闲心率及最大有氧能力的可行性。研究结果表明在递增强度运动过程中87％的受试者都出现了心率拐点。而且随运动强度的递增，完成距离最短者心率拐点偏左、中长者居中、最长者偏右，拐点心率与完成的距离高度显著性相关，表明CONCONI心率拐点具有明显的个体差异性。与乳酸无氧阈相比虽然在精确度上仍需做进一步研究，但如果将ODNODNI拐点心率设定一个范围，用于评定和监测个体最大有氧能力训练还是可行的。     

皮划艇项目有氧能力的评价方法

有氧能力是皮划艇项目运动能力的基础,作为高强度、高乳酸的无氧糖酵解和有氧氧化供能的项目,皮划艇运动员的有氧耐力水平对运动成绩有着决定性的影响。结合皮划艇项目特征及供能特点,分析皮划艇有氧能力测试过程中多种评价方法（3 000 m耐力跑测试、最大摄氧量测试、高强度负荷后血乳酸测试和无氧阈测试等）。在诸多有氧能力评价方法中无氧阈测试有着广泛而有效地使用历史,其中以4 mmol/L乳酸阈（AT4）与个体乳酸阈（IAT）应用最为广泛,而心率无氧阈或可成为皮划艇项目无氧阈研究的新热点。     

赛艇项目三级负荷测试方法的研究

本文对两种三级负荷的测试方法，即4min和8min三级测试方法进行了比较。结果表明，8min测试的心率和血乳酸值均显著性高于4min测试的值（P＜0．01），而4min测试的无氧阈功率则显著性高于8min测试的值（P＜0．05）；在这两种测试方法之间，心率、血乳酸值和无氧阈功率都存在高度的相关性（P＜0．01）。     

13～16岁优秀青少年游泳运动员乳酸阈的分析

以7 m×200 m池内递增负荷测试,通过动态血乳酸变化观察青少年游泳运动员个体乳酸阈,来探索13～16岁青少年游泳运动员血乳酸闲(BLT)的特点,为科学化训练和教学提供依据,为青少年游泳运动员生理机能和能量代谢的纵向研究提供参数.结果显示:13-16岁青少年游泳运动员的乳酸阈平均值为(2.77±0.70)mmol/L,范围在(1.99～3.99)mmol/L,个体差异较明显,青少年运动员乳酸阈较成人偏低.建议在运动实践中,应根据青少年游泳运动员不同年龄段个体乳酸阈特点,科学合理地安排训练强度.     

Changes in blood lactate and pyruvate concentrations and the lactate-to-pyruvate ratio during the lactate minimum speed test

The aim of this study was to assess the responses of blood lactate and pyruvate during the lactate minimum speed test. Ten participants (5 males, 5 females; mean +/- s: age 27.1 +/- 6.7 years, VO 2max 52.0 +/- 7.9 ml kg -1 min -1 ) completed: (1) the lactate minimum speed test, which involved supramaximal sprint exercise to invoke a metabolic acidosis before the completion of an incremental treadmill test (this results in a ‘U-shaped’ blood lactate profile with the lactate minimum speed being defined as the minimum point on the curve); (2) a standard incremental exercise test without prior sprint exercise for determination of the lactate threshold; and (3) the sprint exercise followed by a passive recovery. The lactate minimum speed (12.0 +/- 1.4 km h -1 ) was significantly slower than running speed at the lactate threshold (12.4 +/- 1.7 km h -1 ) (P < 0.05), but there were no significant differences in VO 2 , heart rate or blood lactate concentration between the lactate minimum speed and running speed at the lactate threshold. During the standard incremental test, blood lactate and the lactate-topyruvate ratio increased above baseline values at the same time, with pyruvate increasing above baseline at a higher running speed. The rate of lactate, but not pyruvate, disappearance was increased during exercising recovery (early stages of the lactate minimum speed incremental test) compared with passive recovery. This caused the lactate-to-pyruvate ratio to fall during the early stages of the lactate minimum speed test, to reach a minimum point at a running speed that coincided with the lactate minimum speed and that was similar to the point at which the lactate-to-pyruvate ratio increased above baseline in the standard incremental test. Although these results suggest that the mechanism for blood lactate accumulation at the lactate minimum speed and the lactate threshold may be the same, disruption to normal submaximal exercise metabolism as a result of the preceding sprint exercise, including a three- to five-fold elevation of plasma pyruvate concentration, makes it difficult to interpret the blood lactate response to the lactate minimum speed test. Caution should be exercised in the use of this test for the assessment of endurance capacity.     

Changes in blood lactate and pyruvate concentrations and the lactate-to-pyruvate ratio during the lactate minimum speed test

The aim of this study was to assess the responses of blood lactate and pyruvate during the lactate minimum speed test. Ten participants (5 males, 5 females; mean +/- s: age 27.1+/-6.7 years, VO2max 52.0+/-7.9 ml x kg(-1) x min(-1)) completed: (1) the lactate minimum speed test, which involved supramaximal sprint exercise to invoke a metabolic acidosis before the completion of an incremental treadmill test (this results in a 'U-shaped' blood lactate profile with the lactate minimum speed being defined as the minimum point on the curve); (2) a standard incremental exercise test without prior sprint exercise for determination of the lactate threshold; and (3) the sprint exercise followed by a passive recovery. The lactate minimum speed (12.0+/-1.4 km x h(-1)) was significantly slower than running speed at the lactate threshold (12.4+/-1.7 km x h(-1)) (P < 0.05), but there were no significant differences in VO2, heart rate or blood lactate concentration between the lactate minimum speed and running speed at the lactate threshold. During the standard incremental test, blood lactate and the lactate-to-pyruvate ratio increased above baseline values at the same time, with pyruvate increasing above baseline at a higher running speed. The rate of lactate, but not pyruvate, disappearance was increased during exercising recovery (early stages of the lactate minimum speed incremental test) compared with passive recovery. This caused the lactate-to-pyruvate ratio to fall during the early stages of the lactate minimum speed test, to reach a minimum point at a running speed that coincided with the lactate minimum speed and that was similar to the point at which the lactate-to-pyruvate ratio increased above baseline in the standard incremental test. Although these results suggest that the mechanism for blood lactate accumulation at the lactate minimum speed and the lactate threshold may be the same, disruption to normal submaximal exercise metabolism as a result of the preceding sprint exercise, including a three- to five-fold elevation of plasma pyruvate concentration, makes it difficult to interpret the blood lactate response to the lactate minimum speed test. Caution should be exercised in the use of this test for the assessment of endurance capacity.     

Total Protein of Whole Saliva as a Biomarker of Anaerobic Threshold

Saliva provides a convenient and noninvasive matrix for assessing specific physiological parameters, including some biomarkers of exercise. We investigated whether the total protein concentration of whole saliva (TPWS) would reflect the anaerobic threshold during an incremental exercise test. After a warm-up period, 13 nonsmoking men performed a maximum incremental exercise on a cycle ergometer. Blood and stimulated saliva were collected during the test. The TPWS anaerobic threshold (PAT) was determined using the Dmax method. The PAT was correlated with the blood lactate anaerobic threshold (AT; r = .93, p < .05). No significant difference (p = .16) was observed between PAT and AT. Thus, TPWS provides a convenient and noninvasive matrix for determining the anaerobic threshold during incremental exercise tests.     

乳酸阈强度运动对超重女大学生心肺机能和身体成分的影响

该研究旨在观察乳酸阈强度训练提升超重女大学生心肺机能和改善身体成分的效果。方法：通过递增负荷实验测定超重女大学生个体乳酸阈，绘制血乳酸-走跑强度动力曲线，依此确定运动干预强度及设计运动方案；受试者进行12周乳酸阈强度运动训练；测定实验前后身体成分、肺活量、最大摄氧量、超声心动等指标进行与对照组的对比分析。结果显示：超重女大学生个体乳酸阈为3.75±0.91mmol/L，乳酸阈强度为6.91±0.88km/h，乳酸阈强度训练靶心率为137±12.2次/min；实验组训练后，体脂%、腹部脂肪含量等非常显著的下降，最大摄氧量、肺活量、每博输出量、射血分数显著性提升；对照组无明显变化。结论：12周乳酸阈强度运动锻炼可显著改善超重女大学生的心肺机能和身体成分；本研究得出的乳酸阈强度可作为超重女大学生有氧健身的参考强度。     

Influence of regression model and incremental test protocol on the relationship between lactate threshold using the maximal-deviation method and performance in female runners

This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.     

Eccentric exercise-induced muscle damage dissociates the lactate and gas exchange thresholds

We tested the hypothesis that exercise-induced muscle damage would increase the ventilatory (V(E)) response to incremental/ramp cycle exercise (lower the gas exchange threshold) without altering the blood lactate profile, thereby dissociating the gas exchange and lactate thresholds. Ten physically active men completed maximal incremental cycle tests before (pre) and 48 h after (post) performing eccentric exercise comprising 100 squats. Pulmonary gas exchange was measured breath-by-breath and fingertip blood sampled at 1-min intervals for determination of blood lactate concentration. The gas exchange threshold occurred at a lower work rate (pre: 136 ± 27 W; post: 105 ± 19 W; P < 0.05) and oxygen uptake (VO(2)) (pre: 1.58 ± 0.26 litres · min(-1); post: 1.41 ± 0.14 litres · min(-1); P < 0.05) after eccentric exercise. However, the lactate threshold occurred at a similar work rate (pre: 161 ± 19 W; post: 158 ± 22 W; P > 0.05) and VO(2) (pre: 1.90 ± 0.20 litres · min(-1); post: 1.88 ± 0.15 litres · min(-1); P > 0.05) after eccentric exercise. These findings demonstrate that exercise-induced muscle damage dissociates the V(E) response to incremental/ramp exercise from the blood lactate response, indicating that V(E) may be controlled by additional or altered neurogenic stimuli following eccentric exercise. Thus, due consideration of prior eccentric exercise should be made when using the gas exchange threshold to provide a non-invasive estimation of the lactate threshold.     

The Conconi test is not valid for estimation of the lactate turnpoint in runners

Conconi et al. (1982) reported that an observed deviation from linearity in the heart rate-running velocity relationship determined during a field test in runners coincided with the ‘lactate threshold’. The aim of this study was to assess the validity of the original Conconi test using conventional incremental and constant-load laboratory protocols. Fourteen trained male distance runners (mean ± s : age 22.6 ±3.4 years; body mass 67.6±4.8 kg; peak [Vdot] O 2 66.3 ± 4.7 ml kg -1 min -1) performed a standard multi-stage test for determination of lactate turnpoint and a Conconi test on a motorized treadmill. A deviation from linearity in heart rate was observed in nine subjects. Significant differences were found to exist between running velocity at the lactate turnpoint (4.39 ± 0.20 ms -1) and at deviation from linear heart rate (5.08 ± 0.25 ms -1) (P < 0.01), and between heart rate at the lactate turnpoint (172 ± 10 beats min -1) and at deviation from linearity (186 ± 9 beats min -1) (P < 0.01). When deviation of heart rate from linearity was evident, it occurred at a systematically higher intensity than the lactate turnpoint and at approximately 95% of maximum heart rate. These results were confirmed by the physiological responses of seven subjects, who performed two constant-velocity treadmill runs at 0.14 ms -1 below the running velocity at the lactate turnpoint and that at which the heart rate deviated from linearity. For the lactate turnpoint trial, the prescribed 30 min exercise period was completed by all runners (terminal blood lactate concentration of 2.4 ± 0.5 mM ), while the duration attained in the trial for which heart rate deviated from linearity was 15.9 ± 6.7 min (terminal blood lactate concentration of 8.1 ± 1.8 mM). We concluded that the Conconi test is invalid for the non-invasive determination of the lactate turnpoint and that the deviation of heart rate from linearity represents the start of the plateau at maximal heart rate, the expression of which is dependent upon the specifics of the Conconi test protocol.     

Prediction of maximal lactate steady state in runners with an incremental test on the field

During a maximal incremental ergocycle test, the power output associated with Respiratory Exchange Ratio equal to 1.00 (RER = 1.00) predicts maximal lactate steady state (MLSS). We hypothesised that these results are transferable for runners on the field. Fourteen runners performed a maximal progressive test, to assess the speed associated with RER = 1.00, and several 30 minutes constant velocity tests to determine the speed at MLSS. We observed that the speeds at RER = 1.00, at the second ventilatory threshold (VT2) and at MLSS did not differ (15.7 ± 1.1 km · h?1, 16.2 ± 1.4 km · h?1, 15.5 ± 1.1 km · h?1 respectively). The speed associated with RER = 1.00 was better correlated with that at MLSS (r = 0.79; p = 0.0008) than that at VT2 (r = 0.73; p = 0.002). Neither the concentration of blood lactate nor the heart rate differed between the speed at RER = 1.00 and that at MLSS from the 10th and the 30th minute of the constant velocity test. Bland and Altman analysis showed a fair agreement between the speed at MLSS and that at RER (0.2 ± 1.4 km · h?1). This study demonstrated that the speed associated with RER = 1.00 determined during maximal progressive track running allows a fair estimation of the speed associated with MLSS, markedly decreasing the burden of numerous invasive tests required to assess it.     

The effects of an increasing versus constant crank rate on peak physiological responses during incremental arm crank ergometry

We examined the effects of concomitant increases in crank rate and power output on incremental arm crank ergometry. Ten healthy males undertook three incremental upper body exercise tests to volitional exhaustion. The first test determined peak minute power. The subsequent tests involved arm cranking at an initial workload of 40% peak minute power with further increases of 10% peak minute power every 2 min. One involved a constant crank rate of 70 rev · min(-1), the other an initial crank rate of 50 rev · min(-1) increasing by 10 rev · min(-1) every 2 min. Fingertip capillary blood samples were analysed for blood lactate at rest and exhaustion. Local (working muscles) and cardiorespiratory ratings of perceived exertion (RPE) were recorded at the end of each exercise stage. Heart rate and expired gas were monitored continuously. No differences were observed in peak physiological responses or peak minute power achieved during either protocol. Blood lactate concentration tended to be greater for the constant crank rate protocol (P = 0.06). Test duration was shorter for the increasing than for the constant crank rate protocol. The relationship between local RPE and heart rate differed between tests. The results of this study show that increasing cadence during incremental arm crank ergometry provides a valid assessment of peak responses over a shorter duration but alters the heart rate-local RPE relationship.