Comparison of ergometer- and track-based testing in junior track-sprint cyclists. Implications for talent identification and development.

Talent identification (TID) and talent development (TDE) programmes in track sprint cycling use ergometer- and track-based tests to select junior athletes and assess their development. The purpose of this study was to assess which tests are best at monitoring TID and TDE. Ten male participants (16.2 ± 1.1 year; 178.5 ± 6.0 cm and 73.6 ± 7.6 kg) were selected into the national TID squad based on initial testing. These tests consisted of two 6-s maximal sprints on a custom-built ergometer and 4 maximal track-based tests (2 rolling and 2 standing starts) using 2 gear ratios. Magnitude-based inferences and correlation coefficients assessed changes following a 3-month TDE programme. Training elicited meaningful improvements (80-100% likely) in all ergometer parameters. The standing and rolling small gear, track-based effort times were likely and very likely (3.2 ± 2.4% and 3.3 ± 1.9%, respectively) improved by training. Stronger correlations between ergometer- and track-based measures were very likely following training. Ergometer-based testing provides a more sensitive tool than track-based testing to monitor changes in neuromuscular function during the early stages of TDE. However, track-based testing can indicate skill-based improvements in performance when interpreted with ergometer testing. In combination, these tests provide information on overall talent development.

Ventilatory acclimatisation is beneficial for high-intensity exercise at altitude in elite cyclists.

AIM: The aim of this study was to examine the relationship between ventilatory adaptation and performance during altitude training at 2700 m. METHODS: Seven elite cyclists (age: 21.2 ± 1.1 yr, body mass: 69.9 ± 5.6 kg, height 176.3 ± 4.9 cm) participated in this study. A hypoxic ventilatory response (HVR) test and a submaximal exercise test were performed at sea level prior to the training camp and again after 15 d at altitude (ALT15). Ventilation (VE), end-tidal carbon-dioxide partial pressure (PETCO2) and oxyhaemoglobin saturation via pulse oximetry (SpO2) were measured at rest and during submaximal cycling at 250 W. A hill climb (HC) performance test was conducted at sea level and after 14 d at altitude (ALT14) using a road of similar length (5.5-6 km) and gradient (4.8-5.3%). Power output was measured using SRM cranks. Average HC power at ALT14 was normalised to sea level power (HC%). Multiple regression was used to identify significant predictors of performance at altitude. RESULTS: At ALT15, there was a significant increase in resting VE (10.3 ± 1.9 vs. 12.2 ± 2.4 L·min(-1)) and HVR (0.34 ± 0.24 vs. 0.71 ± 0.49 L·min(-1)·%(-1)), while PETCO2 (38.4 ± 2.3 vs. 32.1 ± 3.3 mmHg) and SpO2 (97.9 ± 0.7 vs. 94.0 ± 1.7%) were reduced (P < .05). Multiple regression revealed ΔHVR and exercise VE at altitude as significant predictors of HC% (adjusted r(2) = 0.913; P = 0.003). CONCLUSIONS: Ventilatory acclimatisation occurred during a 2 wk altitude training camp in elite cyclists and a higher HVR was associated with better performance at altitude, relative to sea level. These results suggest that ventilatory acclimatisation is beneficial for cycling performance at altitude.

The effects of 4 different recovery strategies on repeat sprint-cycling performance.

PURPOSE: To evaluate the effectiveness of different recovery strategies on repeat cycling performance where a short duration between exercise bouts is required. METHODS: Eleven highly trained cyclists (mean ± SD; age = 31 ± 6 y, mass = 74.6 ± 10.6 kg, height = 180.5 ± 8.1 cm) completed 4 trials each consisting of three 30-s maximal sprints (S1, S2, S3) on a cycle ergometer, separated by 20-min recovery periods. In a counterbalanced, crossover design, each trial involved subjects performing 1 of 4 recovery strategies: compression garments (COMP), electronic muscle stimulation (EMS), humidification therapy (HUM), and a passive control (CON). The sprint tests implemented a 60-s preload (at an intensity of 4.5 W/kg) before a 30-s maximal sprint. Mean power outputs (W) for the 3 sprints, in combination with perceived recovery and blood lactate concentration, were used to examine the effect of each recovery strategy. RESULTS: In CON, S2 and S3 were (mean ± SD) -2.1% ± 3.9% and -3.1% ± 4.2% lower than S1, respectively. Compared with CON, COMP resulted in a higher mean power output from S1 to S2 (mean ± 90%CL: 0.8% ± 1.2%; possibly beneficial) and from S1 to S3 (1.2% ± 1.9%; possibly beneficial), while HUM showed a higher mean power output from S1 to S3 (2.2% ± 2.5%; likely beneficial) relative to CON. CONCLUSION: The authors suggest that both COMP and HUM may be effective strategies to enhance recovery between repeated sprint-cycling bouts separated by ~30 min.

Physiological responses to cold water immersion following cycling in the heat.

UNLABELLED: Cold water immersion (CWI) has become a popular means of enhancing recovery from various forms of exercise. However, there is minimal scientific information on the physiological effects of CWI following cycling in the heat. PURPOSE: To examine the safety and acute thermoregulatory, cardiovascular, metabolic, endocrine, and inflammatory responses to CWI following cycling in the heat. METHODS: Eleven male endurance trained cyclists completed two simulated approximately 40-min time trials at 34.3 +/- 1.1 degrees C. All subjects completed both a CWI trial (11.5 degrees C for 60 s repeated three times) and a control condition (CONT; passive recovery in 24.2 +/- 1.8 degrees C) in a randomized cross-over design. Capillary blood samples were assayed for lactate, glucose, pH, and blood gases. Venous blood samples were assayed for catecholamines, cortisol, testosterone, creatine kinase, C-reactive protein, IL-6, and IGF-1 on 7 of the 11 subjects. Heart rate (HR), rectal (Tre), and skin temperatures (Tsk) were measured throughout recovery. RESULTS: CWI elicited a significantly lower HR (CWI: Delta 116 +/- 9 bpm vs. CONT: Delta 106 +/- 4 bpm; P = .02), Tre (CWI: Delta 1.99 +/- 0.50 degrees C vs. CONT: Delta 1.49 +/- 0.50 degrees C; P = .01) and Tsk. However, all other measures were not significantly different between conditions. All participants subjectively reported enhanced sensations of recovery following CWI. CONCLUSION: CWI did not result in hypothermia and can be considered safe following high intensity cycling in the heat, using the above protocol. CWI significantly reduced heart rate and core temperature; however, all other metabolic and endocrine markers were not affected by CWI.

Influence of hydration status on thermoregulation and cycling hill climbing.

PURPOSE: Although dehydration can impair endurance performance, a reduced body mass may benefit uphill cycling by increasing the power-to-mass ratio. This study examined the effects of a reduction in body mass attributable to unreplaced sweat losses on simulated cycling hill-climbing performance in the heat. METHODS: Eight well-trained male cyclists (mean +/- SD: 28.4 +/- 5.7 yr; 71.0 +/- 5.9 kg; 176.7 +/- 4.7 cm; VO2peak: 66.2 +/- 5.8 mL x kg(-1) x min(-1)) completed a maximal graded cycling test on a stationary ergometer to determine maximal aerobic power (MAP). In a randomized crossover design, cyclists performed a 2-h ride at 53% MAP on a stationary ergometer, immediately followed by a cycling hill-climb time-to-exhaustion trial (88% MAP) on their own bicycle on an inclined treadmill (8%) at approximately 30 degrees C. During the 2-h ride, they consumed either 2.4 L of a 7% carbohydrate (CHO) drink (HIGH) or 0.4 L of water (LOW) with sport gels to match for CHO content. RESULTS: After the 2-h ride and before the hill climb, drinking strategies influenced body mass (LOW -2.5 +/- 0.5% vs HIGH 0.3 +/- 0.4%; P < 0.001), HR (LOW 158 +/- 15 vs HIGH 146 +/- 15 bpm; P = 0.03), and rectal temperature (T(re): LOW 38.9 +/- 0.2 vs HIGH 38.3 +/- 0.2 degrees C; P = 0.001). Despite being approximately 1.9 kg lighter, time to exhaustion was significantly reduced by 28.6 +/- 13.8% in the LOW treatment (LOW 13.9 +/- 5.5 vs HIGH 19.5 +/- 6.0 min, P = 0.002), as was the power output for a fixed speed (LOW 308 +/- 28 vs HIGH 313 +/- 28 W, P = 0.003). At exhaustion, T(re) was higher in the LOW treatment (39.5 vs HIGH 39.1 degrees C; P < 0.001), yet peak HR, blood lactate, and glucose were similar. CONCLUSION: Exercise-induced dehydration in a warm environment is detrimental to laboratory cycling hill-climbing performance despite reducing the power output required for a given speed.

Fluid and food intake during professional men's and women's road-cycling tours.

PURPOSE: To quantify the fluid and food consumed during a men's and women's professional road-cycling tour. METHODS: Eight men (age 25 +/- 5 y, body mass 71.4 +/- 7.4 kg, and height 177.4 +/- 4.5 cm) and 6 women (age 26 +/- 4 y, body mass 62.5 +/- 5.6 kg, and height 170.4 +/- 5.2 cm) of the Australian Institute of Sport Road Cycling squads participated in the study. The men competed in the 6-d Tour Down Under (Adelaide, Australia), and the women, in the 10-d Tour De L'Aude (Aude, France). Body mass was recorded before and immediately after the race. Cyclists recalled the number of water bottles and amount of food they had consumed. RESULTS: Men and women recorded body-mass losses of approximately 2 kg (2.8% body mass) and 1.5 kg (2.6% body mass), respectively, per stage during the long road races. Men had an average fluid intake of 1.0 L/h, whereas women only consumed on average 0.4 L/h. In addition, men consumed CHO at the rate suggested by dietitians (average CHO intake of 48 g/h), but again the women failed to reach recommendations, with an average intake of approximately 21 g/h during a road stage. CONCLUSIONS: Men appeared to drink and eat during racing in accordance with current nutritional recommendations, but women failed to reach these guidelines. Both men and women finished their races with a body-mass loss of approximately 2.6% to 2.8%. Further research is required to determine the impact of this loss on road-cycling performance and thermoregulation.

Power output during a professional men's road-cycling tour.

PURPOSE: To quantify the power-output demands of men's road-cycling stage racing using a direct measure of power output. METHODS: Power-output data were collected from 207 races over 6 competition years on 31 Australian national male road cyclists. Subjects performed a maximal graded exercise test in the laboratory to determine maximum aerobic-power output, and bicycles were fitted with SRM power meters. Races were described as flat, hilly, or criterium, and linear mixed modeling was used to compare the races. RESULTS: Criterium was the shortest race and displayed the highest mean power output (criterium 262 +/- 30 v hilly 203 +/- 32 v flat 188 +/- 30 W), percentage total race time above 7.5 W/kg (criterium 15.5% +/- 4.1% v hilly 3.8% +/- 1.7% v flat 3.5% +/- 1.4%) and SD in power output (criterium 250 v hilly 165 v flat 169 W). Approximately 67%, 80%, and 85% of total race time was spent below 5 W/kg for criterium, hilly and flat races, respectively. About 70, 40, and 20 sprints above maximum aerobic-power output occurred during criterium, hilly, and flat races, respectively, with most sprints being 6 to 10 s. CONCLUSIONS: These data extend previous research documenting the demands of men's road cycling. Despite the relatively low mean power output, races were characterized by multiple high-intensity surges above maximum aerobic-power output. These data can be used to develop sport-specific interval-training programs that replicate the demands of competition.

Power output during women's World Cup road cycle racing.

Little information exists on the power output demands of competitive women's road cycle racing. The purpose of our investigation was to document the power output generated by elite female road cyclists who achieved success in FLAT and HILLY World Cup races. Power output data were collected from 27 top-20 World Cup finishes (19 FLAT and 8 HILLY) achieved by 15 nationally ranked cyclists (mean +/- SD; age: 24.1+/-4.0 years; body mass: 57.9+/-3.6 kg; height: 168.7+/-5.6 cm; VO2max 63.6+/-2.4 mL kg(-1) min(-1); peak power during graded exercise test (GXT(peak power)): 310+/-25 W). The GXT determined GXT(peak power), VO2peak lactate threshold (LT) and anaerobic threshold (AT). Bicycles were fitted with SRM powermeters, which recorded power (W), cadence (rpm), distance (km) and speed (km h(-1)). Racing data were analysed to establish time in power output and metabolic threshold bands and maximal mean power (MMP) over different durations. When compared to HILLY, FLAT were raced at a similar cadence (75+/-8 vs. 75+/-4 rpm, P=0.93) but higher speed (37.6+/-2.6 vs. 33.9+/-2.7 km h(-1), P=0.008) and power output (192+/-21 vs. 169+/-17 W, P=0.04; 3.3+/-0.3 vs. 3.0+/-0.4 W kg(-1), P=0.04). During FLAT races, riders spent significantly more time above 500 W, while greater race time was spent between 100 and 300 W (LT-AT) for HILLY races, with higher MMPs for 180-300 s. Racing terrain influenced the power output profiles of our internationally competitive female road cyclists. These data are the first to define the unique power output requirements associated with placing well in both flat and hilly women's World Cup cycling events.