in accordance with the Declaration of Helsinki. Table 1 Physiological Characteristics of the XCO-MTB Cyclists (N = 8) Mean (SD) Range Age, y 22.4 (3.4) 19–28 Height, cm 179 (3) 173–183 Mass, kg 65.4 (3.5) 60.5–72.0 VO 2 max, mL·min −1 ·kg −1 79.9 (5.2) 73.4–88.0 VO 2 max, L·min −1 5.2 (0.3) 4
Cyril Granier, Chris R. Abbiss, Anaël Aubry, Yvon Vauchez, Sylvain Dorel, Christophe Hausswirth and Yann Le Meur
Amelia J. Carr, Philo U. Saunders, Laura A. Garvican-Lewis and Brent S. Vallance
training on elite athletes’ performance, particularly during major competitions, have not been conclusively determined, 4 , 5 but based on the existing literature, potential benefits include improved hemoglobin mass (Hb mass ), maximal oxygen uptake (VO 2 max), 6 submaximal exercise economy, 7 and
Yongming Li, Margot Niessen, Xiaoping Chen and Ulrich Hartmann
extrapolation of the linear relationship between the intensity and oxygen uptake (VO 2 ) during submaximal (35–90% VO 2 max) exercise and calculates the energy into aerobic and anaerobic portions. The 3-component method subdivides the anaerobic portion into lactic and alactic shares. 14 , 15 The anaerobic
Guro Strøm Solli, Pål Haugnes, Jan Kocbach, Roland van den Tillaar, Per Øyvind Torvik and Øyvind Sandbakk
increased blood flow to muscles and elevated baseline oxygen uptake (VO 2 ). 3 , 4 This alters the VO 2 kinetics and leads to a reduction of the initial oxygen deficit, postponing the anaerobic energy contribution to a later stage in the competition. 1 , 4 – 6 However, a too intense or long-lasting warm
Avish P. Sharma, David J. Bentley, Gaizka Mejuto and Naroa Etxebarria
VO 2 max, different submaximal thresholds, and exercise economy or mechanical efficiency. However, as endurance sporting events move closer to city centers aiming to gather crowds and improve spectator experience, an indirect phenomenon has emerged; altered race and consequently physiological demands
Diego Chaverri, Thorsten Schuller, Xavier Iglesias, Uwe Hoffmann and Ferran A. Rodríguez
Assessing cardiopulmonary function during swimming is a complex and cumbersome procedure. Backward extrapolation is often used to predict peak oxygen uptake (V̇O2peak) during unimpeded swimming, but error can derive from a delay at the onset of V̇O2 recovery. The authors assessed the validity of a mathematical model based on heart rate (HR) and postexercise V̇O2 kinetics for the estimation of V̇O2peak during exercise.
34 elite swimmers performed a maximal front-crawl 200-m swim. V̇O2 was measured breath by breath and HR from beat-to-beat intervals. Data were time-aligned and 1-s-interpolated. Exercise V̇O2peak was the average of the last 20 s of exercise. Postexercise V̇O2 was the first 20-s average during the immediate recovery. Predicted V̇O2 values (pV̇O2) were computed using the equation: pV̇O2(t) = V̇O2(t) HRend-exercise/HR(t). Average values were calculated for different time intervals and compared with measured exercise V̇O2peak.
Postexercise V̇O2 (0–20 s) underestimated V̇O2peak by 3.3% (95% CI = 9.8% underestimation to 3.2% overestimation, mean difference = –116 mL/min, SEE = 4.2%, P = .001). The best V̇O2peak estimates were offered by pV̇O2peak from 0 to 20 s (r 2 = .96, mean difference = 17 mL/min, SEE = 3.8%).
The high correlation (r 2 = .86–.96) and agreement between exercise and predicted V̇O2 support the validity of the model, which provides accurate V̇O2peak estimations after a single maximal swim while avoiding the error of backward extrapolation and allowing the subject to swim completely unimpeded.
Nicholas J. Hanson, Sarah C. Martinez, Erik N. Byl, Rachel M. Maceri and Michael G. Miller
least 48 hours between testing sessions. The first visit included a VO 2 max test and familiarization with the laboratory equipment. During the first visit, the participants were also familiarized with the protocol and the rating of perceived exertion (RPE) scale. The second, third, and fourth visits
Gabriela Fischer, Pedro Figueiredo and Luca P. Ardigò
To investigate physiological performance determinants of the partial laps and an overall 22-km handbiking (HB) time trial in athletes with high paraplegia.
Seven male HB athletes with spinal cord injury (lesion levels thoracic 2-8) performed a laboratory maximal incremental test under cardiorespiratory-mechanical monitoring including respiratory-exchange ratio (RER), oxygen uptake (V̇O2), and mechanical power output (PO). Individual first and second ventilatory thresholds (V̇O2VT1 and V̇O2VT2), V̇O2peak, and POpeak were posteriorly identified. Athletes also performed a simulated HB time trial along a 4-lap bike circuit under cardiorespiratory measurement. Overall metabolic cost (C) and %V̇O2peak (ratio of V̇O2 to V̇O2peak) were calculated from race data. Race performance was defined as mean race velocity (v).
athletes completed the 22-km HB time trial in 45 ± 6 min, at 29.9 ± 3.6 km/h, with %V̇O2peak = 0.86 ± 0.10 and RER = 1.07 ± 0.17. V̇O2peak (r = .89, P = .01), POpeak (r = .85, P = .02), V̇O2VT1 (r = .96, P = .001), V̇O2VT2 (r = .92, P = .003), and C (2nd lap, r = .78; 3rd lap, r = .80; and 4th lap, r = .80) were significantly (P < .05) positively correlated with race performance. Within-subjects correlation coefficient revealed a large and significant (r = .68, P < .001) relationship between %V̇O2peak and v.
V̇O2peak, POpeak, ventilatory thresholds, %V̇O2peak, and C appeared to be important physiological performance determinants of HB time trial.
Daniel Muniz-Pumares, Charles Pedlar, Richard J. Godfrey and Mark Glaister
The aim of the study was to determine the effect of supramaximal exercise intensity during constant work-rate cycling to exhaustion on the accumulated oxygen deficit (AOD) and to determine the test–retest reliability of AOD.
Twenty-one trained male cyclists and triathletes (mean ± SD for age and maximal oxygen uptake [V̇O2max] were 41 ± 7 y and 4.53 ± 0.54 L/min, respectively) performed initial tests to determine the linear relationship between V̇O2 and power output, and V̇O2max. In subsequent trials, AOD was determined from exhaustive square-wave cycling trials at 105%, 112.5% (in duplicate), 120%, and 127.5% V̇O2max.
Exercise intensity had an effect (P = .011) on the AOD (3.84 ± 1.11, 4.23 ± 0.96, 4.09 ± 0.87, and 3.93 ± 0.89 L at 105%, 112.5%, 120%, and 127.5% V̇O2max, respectively). Specifically, AOD at 112.5% V̇O2max was greater than at 105% V̇O2max (P = .033) and at 127.5% V̇O2max (P = .022), but there were no differences between the AOD at 112.5% and 120% V̇O2max. In 76% of the participants, the maximal AOD occurred at 112.5% or 120% V̇O2max. The reliability statistics of the AOD at 112.5% V̇O2max, determined as intraclass correlation coefficient and coefficient of variation, were .927 and 8.72%, respectively.
The AOD, determined from square-wave cycling bouts to exhaustion, peaks at intensities of 112.5–120% V̇O2max. Moreover, the AOD at 112.5% V̇O2max exhibits an 8.72% test–retest reliability.
David M. Shaw, Fabrice Merien, Andrea Braakhuis, Daniel Plews, Paul Laursen and Deborah K. Dulson
least 12 months and without a history of recurrent gastrointestinal symptoms volunteered to participate in the study (age, 26.7 ± 5.2 years; body mass, 69.6 ± 8.4 kg; height, 1.82 ± 0.09 m; body mass index, 21.2 ± 1.5 kg/m 2 ; VO 2 peak, 63.9 ± 2.5 ml·kg −1 ·min −1 ; W max, 389.3 ± 50.4 W; hours