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ABSTRACT: We examined 26 professional riders during time trial (TT) competitions of the Grand Tours of cycling (Tour de France and Vuelta Espana; 1997-2003) for the exertional characteristics of contending vs. non-contending (i.e., support) riders. We categorized HR time during TT into training impulse (TRIMP) defined from seasonal VO2max testing [Phase I (<ventilatory threshold (VT approximately 64% VO2max); Phase II (VT-respiratory compensation threshold, approximately 83% VO2max); Phase III >RCP]. Races were: Short TT (<15 km; 8.9+/-2.9 km); Individual TT (>15 km; 48.12+/-8.7 km); Uphill TT (20.0+/-8.7 km) and Team TT (44.1+/-20.9 km). We observed statistically significant event-by-contender interactions for all TT (all, P<0.0001) except the short TT. During uphill TT, contenders exerted fewer total TRIMP (P<0.01), more Zone 3 TRIMP (P<0.05), and fewer Zone 2 TRIMP (P<0.01) vs. non-contenders. For individual TT, contenders accumulated more Total and Zone 3 TRIMP vs. non-contenders (all, P<0.05). Interestingly, during the team TT, contenders accumulated more Zone 3, and fewer Zone 2 TRIMP (all, P<0.05), despite having the opportunity to draft behind other riders while in paceline race formation. During TT events, contending riders compete at a level of exertion corresponding to a higher metabolic demand during the uphill TT, individual TT and team TT.
International Journal of Sports Medicine 02/2009; 30(4):240-4. · 2.43 Impact Factor
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ABSTRACT: The aim of this study was to determine the effects of Rotor, a new cycle crank configuration that effectively allows the pedals to move independently throughout the duty cycle, on indices of endurance cycling performance in trained cyclists. Ten cyclists (5 Rotor users and 5 non-users; age (mean +/- SD): 22 +/- 5 y; VO(2)max: 69.5 +/- 5.1 mL. kg(-1).min(-1)) volunteered to participate in the study. On four separate days, the subjects performed four cycle-ergometer tests, i.e. two incremental tests and two 20-min tests. An imposed crank rate of 75 rev.min(-1) was used during all tests. The incremental protocol started at 112.5 W, and the power output was increased by 37.5 W every 3 min until volitional exhaustion. The 20-min tests were performed at a fixed power output equivalent to 80 % of the highest power output that the cyclists maintained for a complete 3-min period during incremental tests. Both types of tests were performed with the conventional crank system and the Rotor following a counter-balanced, cross-over design. Gas exchange parameters were measured in all the tests and blood lactate was determined at the end of each 3-min period (incremental tests) and at the end of the 20-min tests. A three factor (pedalling system used during the tests x habitual pedalling system x power output [incremental tests] or time [20-min tests]) ANOVA with repeated measures on power output (incremental tests) or time (20-min tests) was used to analyse several indices of performance, e.g. peak power output, VO(2)max, lactate threshold, onset of blood lactate accumulation, economy, delta, and gross efficiency. No differences (p > 0.05) were found between the Rotor and conventional systems for any of the aforementioned variables. It seems that the theoretical advantage brought about by the Rotor system, i.e. improved contra-lateral cooperation of both legs, would be minimized in trained cyclists. Although field studies are needed to assess the possible implications, in terms of actual racing, of the new system, commonly used indicators of endurance cycling performance do not seem to be improved with the Rotor in trained cyclists.
International Journal of Sports Medicine 11/2004; 25(7):479-85. · 2.43 Impact Factor
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ABSTRACT: To investigate the relationship between several physiological variables that can be easily obtained during cycle ergometer gradual testing (for example, peak power output (W(peak)), Vo(2max), or ventilatory threshold (VT)) and actual (>50 km) time trials (TT) time performance during the Tour de France.
We collected data in professional cyclists from the first TT of the 1998 Tour de France (TT1, 58 km distance; n = 6 cyclists) and the first (TT2, 56.5 km; n = 5) and second TT of the 1999 Tour de France (TT3, 57 km; n = 5).
A negative relationship was found between power output (W) at VT (VT(Watt)) and TT final time (s) in TT1 (r = -0.864; p = 0.026; standard error of estimate (SEE) of 73 s; and 95% confidence limits (95% CL) -0.98; -0.18), TT2 (r = -0.77; p = 0.27; SEE of 139 s; and 95% CL -0.98; 0.35), and TT3 (r = -0.923; p = 0.025; SEE of 94 s; and 95% CL -1.00; -0.22).
Actual performance in long TT during the Tour de France (>50 km distance, performed after at least 1-2 weeks of continuous competition), in which some cumulative fatigue inevitably occurs, is related, at least in part, to the power output that elicits the VT. No other routine physiological variable (for example, Vo(2max) or W(peak)) is related to performance in this type of event.
British journal of sports medicine 10/2004; 38(5):636-40. · 2.55 Impact Factor
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ABSTRACT: To determine the effects of electrical stimulation (ES) on oxygen uptake (VO(2)) kinetics and delta efficiency (DE) during gradual exercise. The hypothesis was that ES would attenuate the VO(2)-workload relation and improve DE.
Fifteen healthy, untrained men (mean (SD) age 22 (5) years) were selected. Ten were electrostimulated on both quadriceps muscles with a frequency of 45-60 Hz, with 12 seconds of stimulation followed by eight seconds recovery for a total of 30 minutes a day, three days a week for six weeks. The remaining five subjects were assigned to a control group. A standardised exercise test on a cycle ergometer (ramp protocol, workload increases of 20 W/min) was performed by each subject before and after the experimental period. The slope of the VO(2)-power output (W) relation (deltaVO(2)/deltaW) and DE were calculated in each subject at moderate to high intensities (above the ventilatory threshold-that is, from 50-60% to 100% VO(2)max).
The mean (SEM) values for deltaVO(2)/deltaW and DE had significantly decreased and increased respectively after the six week ES programme (p<0.05; 9.8 (0.2) v 8.6 (0.5) ml O(2)/W/min respectively and 27.7 (0.9) v 31.5 (1.4)% respectively).
ES could be used as a supplementary tool to improve two of the main determinants of endurance capacity, namely VO(2) kinetics and work efficiency.
British Journal of Sports Medicine 04/2003; 37(2):140-3. · 4.14 Impact Factor
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ABSTRACT: The exercise volume and intensity are reported of a male professional cyclist (age 30; VO2max 75.0 ml/kg/min) who successfully completed the 2001 Giro d'Italia (May), Tour de France (July), and Vuelta a España (September). The total exercise time during the Giro, Tour, and Vuelta was 90 hours 44 minutes (5444 minutes), 88 hours 23 minutes (5303 minutes), and 72 hours 59 minutes (4379 minutes) respectively. Heart rate telemetry during the races allowed the exercise intensity to be classified into three phases: I, below the first ventilatory threshold (VT1); II, between VT1 and the second ventilatory threshold (VT2); III, above VT2. Compared with the Giro and Tour, the lower exercise volume of the Vuelta (about 20% less total time) was compensated for by a considerably lower and higher contribution of phases I and III respectively. As a result, the total load (volume x intensity) in the three races was comparable.
British Journal of Sports Medicine 02/2003; 37(5):457-9. · 4.14 Impact Factor
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ABSTRACT: We examined the effects of pre-exercise sodium bicarbonate (NaHCO3) ingestion on the slow component of oxygen uptake (VO2) kinetics in seven professional road cyclists during intense exercise. One hour after ingesting either a placebo or NaHCO3 (0.3 g x kg body mass(-1)), each cyclist (age, 25 +/- 2 years; VO2max, 74.7 +/- 5.9 ml x kg(-1) x min(-1); mean +/- s) performed two bouts of 6 min duration at an intensity of 90% VO2max interspersed by 8 min of active recovery. Gas exchange and blood data (pH, blood lactate concentration and [HCO3-]) were collected during the tests. In both bouts, the slow component of VO2 was defined as the difference between end-exercise VO2 and the VO2 at the end of the third minute. No significant difference was found in the slow component of VO2 between conditions in the first (NaHCO3, 210 +/- 69 ml; placebo, 239 +/- 105 ml) or second trial (NaHCO3, 123 +/- 88 ml; placebo, 197 +/- 101 ml). In conclusion, pre-exercise NaHCO3 ingestion did not significantly attenuate the VO2 slow component of professional road cyclists during high-intensity exercise.
J Sports Sci. 01/2003; 21(1):39-47..
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ABSTRACT: PURPOSE: To compare the total exercise loads (intensity x volume) of the Vuelta a Espana and Tour de France during the last year. METHODS: Seven professional road cyclists (28 +/- 1 yr; [OV0312]O(2max): 74.6 +/- 2.2 mL.kg-1.min-1) who participated in both Tour and Vuelta during the years 1997, 1999, 2000, or 2001 were collected as subjects. They wore a heart rate (HR) telemeter during each stage of the two races, and exercise intensity was divided into three phases according to the reference HR values obtained during a previous ramp cycle-ergometer test: phase I (<ventilatory threshold (VT)), phase II (between VT and the respiratory compensation point (RCP)) and phase III (>RCP). Total volume and intensity were integrated as a single variable. The score for volume x intensity in each phase was computed by multiplying the accumulated duration in this phase by a multiplier for this particular phase. The total score for Tour and Vuelta was obtained by summating the results of the three phases. RESULTS: The total loads (volume x intensity) did not significantly differ between the two races (P > 0.05), despite a significantly longer total exercise time of the Tour (P < 0.05) (5552 +/- 176 vs 5086 +/- 290 min). CONCLUSION: The physiological loads imposed on cyclists' bodies do not differ between the Tour and Vuelta, despite the longer duration of daily stages in the former race.
Med Sci Sports Exerc. 01/2003; 35(5):872-8..
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ABSTRACT: To determine the influence of lactic acidosis, the Bohr effect, and exercise induced hyperkalaemia on the occurrence of the heart rate deflection point (HRDP) in elite (professional) cyclists.
Sixteen professional male road cyclists (mean (SD) age 26 (1) years) performed a ramp test on a cycle ergometer (workload increases of 5 W/12 s, averaging 25 W/min). Heart rate (HR), gas exchange parameters, and blood variables (lactate, pH, P(50) of the oxyhaemoglobin dissociation curve, and K(+)) were measured during the tests.
A HRDP was shown in 56% of subjects at about 88% of their maximal HR (HRDP group; n = 9) but was linear in the rest (No-HRDP group; n = 7). In the HRDP group, the slope of the HR-workload regression line above the HRDP correlated inversely with levels of K(+) at the maximal power output (r = -0.67; p<0.05).
The HRDP phenomenon is associated, at least partly, with exercise induced hyperkalaemia.
British Journal of Sports Medicine 05/2002; 36(2):113-7. · 4.14 Impact Factor
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ABSTRACT: The purpose of this study was to analyze the effects of caffeine ingestion on the slow component of oxygen uptake (DeltaVO(2)) during high-intensity endurance exercise. Nine subjects (8 male and 1 female; age: 21 +/- 1 years; VO(2 max): 57.9 +/- 1.5 ml kg(-1) min(-1)) performed two 9-min tests on a treadmill at a running velocity eliciting 90% of their VO(2 max), 60 min after ingesting either a placebo capsule (PLAC) or a capsule containing a caffeine dose of 5 mg (kg body mass)(-1) [CAFF]. The mean values of DeltaVO(2) were significantly lower in CAFF than in PLAC (83 +/- 31 ml min(-1) vs. 167 +/- 26 ml min(-1), respectively; p < 0.05). These findings suggest that the ergogenic effect of caffeine in a high-intensity endurance exercise shown in previous research may be partly mediated by a possible attenuation of the VO(2) slow component.
The Japanese Journal of Physiology 01/2002; 51(6):761-4. · 1.04 Impact Factor
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ABSTRACT: Objective: To investigate the relationship between several physiological variables that can be easily obtained during cycle ergometer gradual testing (for example, peak power output (Wpeak), VO2max, or ventilatory threshold (VT)) and actual (>50 km) time trials (TT) time performance during the Tour de France.
