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1.
Until recently, the physiological demands of cycling competitions were mostly reflected by the measurement of heart rate and the indirect estimation of exercise intensity. The purpose of this case study was to illustrate the varying power output of a professional cyclist during flat and mountain stages of a Grand Tour (Giro d'Italia). Nine stage recordings of a cyclist of the 2005 Giro d'Italia were monitored using a mobile power measurement device (SRM Trainingssystem, Julich, Germany), which recorded direct power output and heart rate. Stages were categorized into flat (n = 5) and mountain stages (n = 4). Data were processed electronically, and the overall mean power in flat and mountain stages and maximal mean power for various durations were calculated. Mean power output was 132 W +/- 26 (2.0 W x kg(-1) +/- 0.4) for the flat and 235 W +/- 10 (3.5 W x kg(-1) +/- 0.1) for the mountain stages. Mountain stages showed higher maximal mean power (367 W) for longer durations (1800 s) than flat stages (239 W). Flat stages are characterized by a large variability of power output with short bursts of high power and long periods with reduced intensity of exercise, whereas mountain stages mostly require submaximal, constant power output over longer periods.  相似文献   

2.
This study evaluated the changes in ratios of different intensity (rating of perceived exertion; RPE, heart rate; HR, power output; PO) and load measures (session-RPE; sRPE, individualized TRIMP; iTRIMP, Training Stress Score?; TSS) in professional cyclists. RPE, PO and HR data was collected from twelve professional cyclists (VO2max 75 ± 6 ml?min?kg?1) during a two-week baseline training period and during two cycling Grand Tours. Subjective:objective intensity (RPE:HR, RPE:PO) and load (sRPE:iTRIMP, sRPE:TSS) ratios and external:internal intensity (PO:HR) and load (TSS:iTRIMP) ratios were calculated for every session. Moderate to large increases in the RPE:HR, RPE:PO and sRPE:TSS ratios (d = 0.79–1.79) and small increases in the PO:HR and sRPE:iTRIMP ratio (d = 0.21–0.41) were observed during Grand Tours compared to baseline training data. Differences in the TSS:iTRIMP ratio were trivial to small (d = 0.03–0.27). Small to moderate week-to-week changes (d = 0.21–0.63) in the PO:HR, RPE:PO, RPE:HR, TSS:iTRIMP, sRPE:iTRIMP and sRPE:TSS were observed during the Grand Tour. Concluding, this study shows the value of using ratios of intensity and load measures in monitoring cyclists. Increases in ratios could reflect progressive fatigue that is not readily detected by changes in solitary intensity/load measures.  相似文献   

3.
Abstract

Until recently, the physiological demands of cycling competitions were mostly reflected by the measurement of heart rate and the indirect estimation of exercise intensity. The purpose of this case study was to illustrate the varying power output of a professional cyclist during flat and mountain stages of a Grand Tour (Giro d'Italia). Nine stage recordings of a cyclist of the 2005 Giro d'Italia were monitored using a mobile power measurement device (SRM Trainingssystem, Julich, Germany), which recorded direct power output and heart rate. Stages were categorized into flat (n = 5) and mountain stages (n = 4). Data were processed electronically, and the overall mean power in flat and mountain stages and maximal mean power for various durations were calculated. Mean power output was 132 W ± 26 (2.0 W · kg?1 ± 0.4) for the flat and 235 W ± 10 (3.5 W · kg?1 ± 0.1) for the mountain stages. Mountain stages showed higher maximal mean power (367 W) for longer durations (1800 s) than flat stages (239 W). Flat stages are characterized by a large variability of power output with short bursts of high power and long periods with reduced intensity of exercise, whereas mountain stages mostly require submaximal, constant power output over longer periods.  相似文献   

4.
This study analysed the evolution of the physical potential of a twice top-10 Grand Tour cycling finisher (Tour de France and Vuelta a España) whose training was monitored between the ages of 18 and 23 years. The world-class cyclist’s power output (PO) data and training indices were analysed over six years to determine the evolution of his record power profile and training load (TL), which were estimated by using the session rating of perceived exertion (RPE) method. The total annual duration and TL increased through six seasons by 79% and 83%, respectively. The record POs in all exercise intensity zones improved over the six years. The increases in TL, monotony (+34%) and strain (+162%) from the junior category to the world-class level significantly correlated with an improvement in his aerobic potential, which was characterised by an increase in the record POs between 5 min and 4 h. This case study of the performance level and training parameters of a world-class cyclist provides comprehensive insight into the evolution of a cyclist to the top level. Furthermore, determining the record power profile of this athlete over six competitive seasons illuminates the maturation of the physical potential of a top-10 Grand Tour finisher.  相似文献   

5.
It is not known whether the seated or standing position favours performance during intensive bouts of uphill cycling. The following hypotheses were therefore tested: (1) the standing position results in better performance at a high power output, while (2) the seated position is best at a moderate power output. We also assessed the seated-standing transition intensity, above which seated cycling should be superseded by standing cycling for maximization of performance. Ten male cyclists (mean age 27 years, s = 3; height 1.82 m, s = 0.07; body mass 75.2 kg, s = 7.0; VO2max 70.0 ml.kg(-1).min(-1), s = 5.2) performed seated and standing treadmill cycling to exhaustion at 10% grade and at four power outputs ranging from 86% to 165% of their power output at maximal oxygen uptake (Wmax). Power output at maximal oxygen uptake was obtained during determination of VO2max. There was no difference in time to exhaustion between the two cycling positions at 86% of Wmax (P = 0.29). All participants performed best at the highest power output (165% of Wmax) when standing (P = 0.002). An overall seated-standing transition intensity of 94% of Wmax was identified. Thus, in general, cyclists may choose either the standing or seated position for maximization of performance at a submaximal intensity of 86% of Wmax, while the standing position should be used at intensities above 94% of Wmax and approaching 165% of Wmax.  相似文献   

6.
The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600–4000?m) of 4-km TT (316?±?89?W) was statistically higher than power output measured at the end of the constant workload exercise (211?±?42?W). The 4-km TT produced higher values of blood lactate concentration (8.8?±?2.1?mmol?L?1) than the constant workload test (7.8?±?2.1?mmol?L?1). The heart rate recovery measured at 60?s (constant workload: 37?±?7?bpm; 4-km TT: 30?±?6) and 120?s (constant workload: 57?±?9?bpm; 4-km TT: 51?±?9?bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570?s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.  相似文献   

7.
Abstract

The present study examined the effects of differing intensity levels of acute exercise on preadolescent academic ability. In a repeated measures design, 18 preadolescent participants (mean age±S.D.=9.8±1.4 years: 9 male and 9 female) completed the Wide Range Achievement Test (WRAT 4) following 20 minutes of rest, 20-minutes on a cycling ergometer at 50% maximal heart rate reserve (HRR), and 20-minutes on a cycling ergometer at 75% HRR on separate days. Exercise was found to improve spelling irrespective of intensity level. Moderate levels of exercise improved reading although the effect of high levels of intensity is less clear. Both intensity levels impaired arithmetic, whilst sentence comprehension was unaffected. These findings further support the past research that indicates acute bouts of exercise can selectively improve cognition in preadolescent children. However, the present study finds no support for the notion that increasing the intensity of exercise accentuates benefits.  相似文献   

8.
The pre-event warm-up or “priming” routine for optimising cycling performance is not well-defined or uniform to a specific event. We aimed to determine the effects of varying the intensity of priming on 3 km cycling performance. Ten endurance-trained male cyclists completed four 3 km time-trials (TT) on four separate occasions, each preceded by a different priming strategy including “self-selected” priming and three intermittent priming strategies incorporating 10 min of constant-load cycling followed by 5 × 10 s bouts of varying relative intensity (100% and 150% of peak aerobic power, Wpeak, and all-out priming). The self-selected priming trial (379 ± 44 W) resulted in similar mean power during the 3 km TT to intermittent priming at 100% (376 ± 45 W; ?0.7%; unclear) and 150% (374 ± 48 W; ?1.5%, unclear) of Wpeak, but significantly greater than all-out priming (357 ± 45 W; ?5.8%, almost certainly harmful). Differences between intermittent and self-selected priming existed with regards to heart rate (6.2% to 11.5%), blood lactate (?22.9% to 125%) and VO2 kinetics (?22.9% to 8.2%), but these were not related to performance outcomes. In conclusion, prescribed intermittent priming strategies varying in intensity did not substantially improve 3 km TT performance compared to self-selected priming.  相似文献   

9.
This study aimed to describe the effect of compression garments on middle cerebral artery blood flow velocity (MCAv) in relation to cognitive and exercise performance whilst cycling. In a randomised-controlled-cross-over design, 15 well-trained male cyclists were recruited to participate in three identical trials wearing loose fitting shorts (control), low-grade, or medium-grade compression garments. The protocol involved four 8?min increments of cycling at 30%, 50%, 70%, and 85% maximal power output and a 4?km time-trial. Participants undertook a cognitive Stroop task at baseline and at the midpoint of each increment. MCAv was monitored with Transcranial Doppler Ultrasonography. Mean arterial pressure (MAP) and partial pressure of end-tidal CO2 (PetCO2) were measured throughout. MCAv, MAP, PetCO2, and reaction time of the complex Stroop task were influenced by exercise intensity, but not compression garments. Compression garments significantly affected cognitive accuracy in the complex Stroop task such that low-grade compression appeared to enhance cognitive accuracy in comparison to the control condition at the highest intensity (p?=?.010). Time-trial performance did not differ between the control (338.0?±?17.3 s), low-grade (338.7?±?18.7 s), or medium-grade (342.2?±?19.3 s) conditions (p?=?.114). Compression garments did not affect MCAv during exercise or time-trial performance, but compression may be beneficial for improved cognitive accuracy during high-intensity exercise. Further research is required to elucidate the potential impact on cognitive performance.  相似文献   

10.
采用功率自行车或心率遥测仪对WCBA优秀女篮运动员进行测试,通过血乳酸和心率的变化对训练负荷进行监控和评价,为女篮运动员体能训练提供科技支撑。研究结果发现运动员功率自行车或训练中大强度训练血乳酸和脉搏呈现不稳定状态,持续一段时间后,运动员的专项体能明显下降,反应延迟,注意力分散,通过短暂调控,运动员恢复到较为理想的状态。研究结论:在WCBA运动队训练中,建议使用心率和血乳酸指标监控和评价WCBA的训练负荷。通过对WCBA运动员训练负荷(心率和血乳酸)的测定,可以反映训练负荷强度的大小,对运动员承受训练负荷的能力和训练后的状态进行综合评价,提高训练效果。训练中应根据心率和血乳酸指标变更训练计划,调整运动强度,防止疲劳的产生。运用心率和血乳酸指标加强科学化训练,提高WCBA女篮的训练质量和专项负荷能力。  相似文献   

11.
We test the hypothesis that breathing oxygen-enriched air (F(I)O(2) = 100%) maintains exercise performance and reduces fatigue during intervals of maximal-intensity cycling. Ten well-trained male cyclists (age 25 ± 3 years; peak oxygen uptake 64.8 ± 6.2 ml · kg(-1) · min(-1); mean ± s) were exposed to either hyperoxic or normoxic air during the 6-min intervals between five 30-s sessions of cycling at maximal intensity. The concentrations of lactate and hydrogen ions [H(+)], pH, base excess, oxygen partial pressure, and oxygen saturation in the blood were assessed before and after these sprints. The peak (P = 0.62) and mean power outputs (P = 0.83) with hyperoxic and normoxic air did not differ. The partial pressure of oxygen was 4.2-fold higher after inhaling hyperoxic air, whereas lactate concentration, pH, [H(+)], and base excess (P ≥ 0.17) were not influenced. Perceived exertion towards the end of the 6-min periods after the fourth and fifth sprints (P < 0.05) was lower with hyperoxia than normoxia (P < 0.05). These findings demonstrate that the peak and mean power outputs of athletes performing intervals of maximal-intensity cycling are not improved by inhalation of oxygen-enriched air during recovery.  相似文献   

12.
The Akt-mTOR-p70S6k-4E-BP1 signaling pathway is a well-considered regulator of protein synthesis in the context of strength training. This process is essential for exercise-induced skeletal muscle growth. The objective of this review article was to analyze the design of acute resistance training protocols and evaluate the possible impact of different loading conditions on the activation of growth-related signaling cascades in human skeletal muscle. In all, 12 human studies were included in this review. The training intensity in the studies varied between 30% 1RM (one repetition maximum) and maximal load. The signaling proteins were measured in a time range between immediately and 24?h after training.The phosphorylation of all signaling proteins increased to different levels after resistance training, tending to baseline more than 6?h post training. In particular, the hypertrophic associated p70S6k showed the highest phosphorylation acutely after the load and decreased consistently after 6?h. Training intensity and volume seemed to have an influence on the extent of protein phosphorylation, which, however, was not systematic or consistent. An obvious training methodological consequence (load and volume) for hypertrophic resistance training regime could not be devised. Further research is required to systematically vary training parameters to determine the influence of a certain stress zone on the signaling activation. Future research should aim to identify the ideal level of training intensity necessary to achieve the greatest possible extent of intramuscular anabolic signaling through intense activation of the signaling cascade to induce growth in human skeletal muscle.  相似文献   

13.
Abstract

Road cycling ranks among the most intense endurance exercises. Previous studies and mathematical models describing road cycling have not analysed performances per se. We describe the evolution of road cycling performance over the past 116 years. We studied the top ten cyclists' mean speeds in eight famous classic races and three European Grand Tours, using a previously published multi-exponential model that highlights the different progression periods of an event during the century. In addition, we measured an indicator of difficulty for the Tour de France by calculating the climbing index (i.e. the total altitude climbed over total distance). The eleven races' mean speed increased progressively from 23.13 km · h?1 in 1892 to 41.19 ± 2.03 km · h?1 in 2008. Road cycling development, like other quantifiable disciplines, fits a piecewise progression pattern that follows three periods: before, between, and after the two World Wars. However, a fourth period begins after 1993, providing a speed progression of 6.38% from the third one. The Tour de France's climbing index also provided insight into a recent paradoxical relationship with speeds: when the climbing index increased, the winner's speed also increased. Our results show a major improvement (6.38%) in road cycling performance in the last 20 years and question the role of extra-physiological parameters in this recent progression.  相似文献   

14.
Abstract

Practice plays an important role in skill acquisition, although not all practice is of equal quality. We examined the types of team practice activities in four groups of youth cricket players. The groups were recreational- and elite-children (9 to 12 years of age) and recreational- and elite-adolescent players (13 to 17 years of age). Time motion analysis recorded the duration in two types of practice activities, namely, Training Form and Playing Form. Training Form is mainly drill-type activities, whereas Playing Form is mainly games-based activities. Training Form activity is thought to contain fewer opportunities to develop the perceptual, cognitive and motor skills required for successful performance in competition when compared to Playing Form. Session duration was a mean value of 95, s?=?29?min. All players combined spent 69% of session time in Training Form activity and 19% in Playing Form, with the remaining percentage of time spent in transition between activities. Recreational-children spent around half of their time in Playing Form activity, whereas both elite and adolescent groups spent little or no time in this activity. Findings from this research highlight a gap between research and practice that may not be optimal for skill acquisition.  相似文献   

15.
目的:研究补充FDP对递增运动负荷训练至力竭的运动性疲劳大鼠各时相心肌SOD、MDA、LDH 和CK的影响及其变化规律.方法:实验以SD大鼠为研究对象,测定其运动训练5周、力竭后即刻、力竭后6h、力竭后24h心肌中LDH、CK、SOD活性和MDA水平,安静对照组则测定其安静状态下上述相同的实验指标.结果:①中小强度运动训练5周后,FDP组心肌各指标与对照组相比没有显著性意义;②力竭后即刻及恢复各时相FDP组心肌CK和LDH活性均高于对照组;③力竭即刻及恢复各时相,FDP组心肌SOD活性和SOD/MDA的比值均显著高于对照组,MDA含量显著性低于运动对照组.结论:FDP能提高运动力竭后即刻及恢复期各时相心肌LDH、CK、SOD活性和SOD/MDA的比值,降低MDA的生成;说明FDP能促进心肌组织糖酵解,改善心肌的能量供应,提高抗脂质过氧化作用,对心肌细胞具有良好的保护作用.  相似文献   

16.
In this study, we assessed age-related changes in indoor 16.1-km cycling time-trial performance in 40 competitive male cyclists aged 25-63 years. Participants completed two tests: (1) a maximal ramped Kingcycle ergometer test, with maximal ramped minute power (RMPmax, W) recorded as the highest mean external power during any 60 s and maximal heart rate (HRmax, beats min(-1)) as the highest value during the test; and (2) an indoor Kingcycle 16.1-km time-trial with mean external power output (W), heart rate (beats min(-1)), and pedal cadence (rev min(-1)) recorded throughout the event. Results revealed age-related declines (P < 0.05) in absolute and relative time-trial external power output [(24 W (7.0%) per decade], heart rate [7 beats min(-1) (3.87%) per decade], and cadence [3 rev min(-1) (3.1%) per decade]. No relationships (P > 0.05) were observed for mean power output and heart rate recorded during the time-trial versus age when expressed relative to maximal ramped minute power and maximal heart rate respectively. Strong relationships (P < 0.05) were observed for maximal ramped minute power and time-trial power (r= 0.95) and for maximal heart rate and time-trial heart rate (r= 0.95). Our results show that indoor 16.1-km time-trial performance declines with age but relative exercise intensity (%RMPmax and %HRmax) does not change.  相似文献   

17.
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   


18.
We tested the hypothesis that work-matched supramaximal intermittent warm-up improves final-sprint power output to a greater degree than submaximal constant-intensity warm-up during the last 30?s of a 120-s supramaximal exercise simulating the final sprint during sports events lasting approximately 2?min. Ten male middle-distance runners performed a 120-s supramaximal cycling exercise consisting of 90?s of constant-workload cycling at a workload corresponding to 110% maximal oxygen uptake (VO2max) followed by 30?s of maximal-effort cycling. This exercise was preceded by 1) no warm-up (Control), 2) a constant-workload cycling warm-up at a workload of 60%VO2max for 6?min and 40?s, or 3) a supramaximal intermittent cycling warm-up for 6?min and 40?s consisting of 5 sets of 65?s of cycling at a workload of 46%VO2max?+?15?s of supramaximal cycling at a workload of 120%VO2max. By design, total work was matched between the two warm-up conditions. Supramaximal intermittent and submaximal constant-workload warm-ups similarly increased 5-s peak (590?±?191 vs. 604?±?215W, P?=?0.41) and 30-s mean (495?±?137 vs. 503?±?154W, P?=?0.48) power output during the final 30-s maximal-effort cycling as compared to the no warm-up condition (5-s peak: 471?±?165W; 30-s mean: 398?±?117W). VO2 during the 120-s supramaximal cycling was similarly increased by the two warm-ups as compared to no-warm up (P?≤?0.05). These findings show that work-matched supramaximal intermittent and submaximal constant-workload warm-ups improve final sprint (～30?s) performance to similar extents during the late stage of a 120-s supramaximal exercise bout.  相似文献   

19.
Exercise has been demonstrated to have considerable effects upon haemostasis, with activation dependent upon the duration and intensity of the exercise bout. In addition, markers of coagulation and fibrinolysis have been shown to possess circadian rhythms, peaking within the morning (0600–1200?h). Therefore, the time of day in which exercise is performed may influence the activation of the coagulation and fibrinolytic systems. This study aimed to examine coagulation and fibrinolytic responses to short-duration high-intensity exercise when completed at different times of the day. Fifteen male cyclists (VO2max: 60.3?±?8.1?ml?kg?1?min?1) completed a 4-km cycling time trial (TT) on five separate occasions at 0830, 1130, 1430, 1730 and 2030. Venous blood samples were obtained pre- and immediately post-exercise, and analysed for tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombin–anti-thrombin complexes (TAT) and D-Dimer. Exercise significantly increased plasma concentrations of TF (p?p?p?p?p?=?.004) and TFPI (p?=?.031), with 0830 greater than 1730 (p .001), while 1730 was less than 2030?h (p?=?.008), respectively. There was no significant effect of time of day for TAT (p?=?.364) and D-Dimer (p?=?.228). Power output, TT time and heart rate were not significantly different between TTs (p?>?.05); however, percentage VO2max was greater at 1730 when compared to 2030 (p?=?.04). Due to a time-of-day effect present within TF, peaking at 0830, caution should be applied when prescribing short-duration high-intensity exercise bout within the morning in populations predisposed to hypercoagulability.  相似文献   

20.
Abstract

Research with cyclists suggests a decreased load on the lower limbs by placing the shoe cleat more posteriorly, which may benefit subsequent running in a triathlon. This study investigated the effect of shoe cleat position during cycling on subsequent running. Following bike-run training sessions with both aft and traditional cleat positions, 13 well-trained triathletes completed a 30?min simulated draft-legal triathlon cycling leg, followed by a maximal 5?km run on two occasions, once with aft-placed and once with traditionally placed cleats. Oxygen consumption, breath frequency, heart rate, cadence and power output were measured during cycling, while heart rate, contact time, 200?m lap time and total time were measured during running. Cardiovascular measures did not differ between aft and traditional cleat placement during the cycling protocol. The 5?km run time was similar for aft and traditional cleat placement, at 1084?±?80?s and 1072?±?64?s, respectively, as was contact time during km 1 and 5, and heart rate and running speed for km 5 for the two cleat positions. Running speed during km 1 was 2.1%?±?1.8 faster (P?<?0.05) for the traditional cleat placement. There are no beneficial effects of an aft cleat position on subsequent running in a short distance triathlon.  相似文献   

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