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Barry Braun, Priscilla M. Clarkson, Patty S. Freedson, and Randall L. Kohl

The effects of dietary supplementation with Coenzyme Q10 (CoQlO), a reputed performance enhancer and antioxidant, on physiological and biochemical parameters were examined. Ten male bicycle racers performed graded cycle ergometry both before and after being given 100 mg per day CoQlO or placebo for 8 weeks. Analysis of variance showed a significant difference between groups for postsupplementation serum CoQ10. Although both groups demonstrated training related improvements in all physiological parameters over the course of the study, there were no significant differences between the two groups (p>.05). Both groups showed a 21 % increase in serum MDA (an index of lipid peroxidation) after the presupplementation exercise test. After 8 weeks this increase was only 5 % , and again was identical for both groups. Supplementation with CoQlO has no measurable effect on cycling performance, VO2max, submaximal physiological parameters, or lipid peroxidation. However, chronic intense training seems to result in marked attenuation of exercise-induced lipid peroxidation.

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Madison Taylor, Nicki Almquist, Bent Rønnestad, Arnt Erik Tjønna, Morten Kristoffersen, Matt Spencer, Øyvind Sandbakk, and Knut Skovereng

highest average PO (PO 20min ) possible. The participant self-selected their starting PO, which was replicated at PREP to ensure the same pacing conditions. VO 2 was measured from minute 4 to 5, 9 to 10, and 15 to 20. Mean performance VO 2 was determined as the average of all recorded VO 2 measurements

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Ana Sousa, Pedro Figueiredo, David Pendergast, Per-Ludvik Kjendlie, João P. Vilas-Boas, and Ricardo J. Fernandes

Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central—O2 delivery and transportation to the working muscles—or peripheral factors—O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers’ behavior in competition and to develop efficient training programs.

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Philo U. Saunders, Amanda J. Cox, Will G. Hopkins, and David B. Pyne

It is unclear whether physiological measures monitored in an incremental treadmill test during a training season provide useful diagnostic information about changes in distance running performance.

Purpose:

To quantify the relationship between changes in physiological measures and performance (peak running speed) over a training season.

Methods:

Well-trained distance runners (34 males; VO2max 64 ± 6 mL⋅kg-1⋅min-1, mean ± SD) completed four incremental treadmill tests over 17 wk. The tests provided values of peak running speed, VO2max, running economy, and lactate threshold (as speed and %VO2max). The physiological measures were included in simple and multiple linear regression models to quantify the relationship between changes in these measures and changes in peak speed.

Results:

The typical within-subject variation in peak speed from test to test was 2.5%, whereas those for physiological measures were VO2max (mL⋅min-1⋅kg-1) 3.0%, economy (m⋅kg⋅mL–1) 3.6%, lactate threshold (%VO2max) 8.7%, and body mass 1.8%. In simple models these typical changes predicted the following changes in performance: VO2max 1.4%, economy 0.8%, lactate threshold –0.3%, and body mass –0.2% (90% confidence limits ~±0.7%); the corresponding correlations with performance were 0.57, 0.33, –0.05, and –0.13 respectively (~±0.20). In a multiple linear regression model, the contribution of each physiological variable to performance changed little after adjustment for the other variables.

Conclusion:

Change in VO2max in an incremental test during a running season is a good predictor of change in peak running speed, change in running economy is a moderate predictor, and lactate threshold and body mass provide little additional information.

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Thiago Oliveira Borges, Ben Dascombe, Nicola Bullock, and Aaron J. Coutts

This study aimed to profile the physiological characteristics of junior sprint kayak athletes (n = 21, VO2max 4.1 ± 0.7 L/min, training experience 2.7 ± 1.2 y) and to establish the relationship between physiological variables (VO2max, VO2 kinetics, muscle-oxygen kinetics, paddling efficiency) and sprint kayak performance. VO2max, power at VO2max, power:weight ratio, paddling efficiency, VO2 at lactate threshold, and whole-body and muscle oxygen kinetics were determined on a kayak ergometer in the laboratory. Separately, on-water time trials (TT) were completed over 200 m and 1000 m. Large to nearly perfect (−.5 to −.9) inverse relationships were found between the physiological variables and on-water TT performance across both distances. Paddling efficiency and lactate threshold shared moderate to very large correlations (−.4 to −.7) with 200- and 1000-m performance. In addition, trivial to large correlations (−.11 to −.5) were observed between muscle-oxygenation parameters, muscle and whole-body oxygen kinetics, and performance. Multiple regression showed that 88% of the unadjusted variance for the 200-m TT performance was explained by VO2max, peripheral muscle deoxygenation, and maximal aerobic power (P < .001), whereas 85% of the unadjusted variance in 1000-m TT performance was explained by VO2max and deoxyhemoglobin (P < .001). The current findings show that well-trained junior sprint kayak athletes possess a high level of relative aerobic fitness and highlight the importance of the peripheral muscle metabolism for sprint kayak performance, particularly in 200-m races, where finalists and nonfinalists are separated by very small margins. Such data highlight the relative aerobic-fitness variables that can be used as benchmarks for talent-identification programs or monitoring longitudinal athlete development. However, such approaches need further investigation.

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Wolfgang Schobersberger, Michael Mairhofer, Simon Haslinger, Arnold Koller, Christian Raschner, Sibylle Puntscher, and Cornelia Blank

performance; VO 2 max, maximal oxygen uptake; VTP2, individual ventilatory turn point 2. Performance Data and FIS Ranking The mean values for the descriptive performance data, that is, the maximum exercise capacity ( P max and VO 2 max), remained stable over the 7 seasons, being within the range of 4.37 to 4

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Jan-Michael Johansen, Sondre Eriksen, Arnstein Sunde, Øystein B. Slettemeås, Jan Helgerud, and Øyvind Støren

the improvement in MAS, which was at the approximate same level. This is in accordance with the framework of Joyner and Coyle, 7 defining performance velocity as the product of performance VO 2 (VO 2 max and lactate threshold), performance O 2 deficit, and gross mechanical efficiency. As MAS is the

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Carolina F. Wilke, Felipe Augusto P. Fernandes, Flávio Vinícius C. Martins, Anísio M. Lacerda, Fabio Y. Nakamura, Samuel P. Wanner, and Rob Duffield

.3 (1.0) 20.8 (3.4) 24.0 (6.5) b .027 0.89/−0.55/1.04  Body mass, kg 68.2 (10.8) 70.0 (3.2) 70.4 (6.1) .857 0.19/−0.07/0.22  Stature, cm 174.2 (7.1) 175.1 (7.0) 172.7 (3.4) .778 0.12/0.40/−0.24 Physical performanceVO 2 max, mL O 2 ·kg −1 ·min −1 48.9 (4.0) 54.2 (4.5) 51.9 (3.6) .128 1

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Andrew J. Carnes and Sara E. Mahoney

CFE. This result affirms earlier evidence supporting POL, which presently improved performance, VO 2 max, and BC in recreational runners. It also provides preliminary evidence that CFE can deliver comparable enhancement of performance and BC, but potentially smaller gains in VO 2 max. The similar

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Herbert Wagner, Patrick Fuchs, Andrea Fusco, Philip Fuchs, Jeffrey W. Bell, and Serge P. von Duvillard

better aerobic performance (VO 2 general and running time in the incremental treadmill-running test). These results in general physical performance are in agreement with previous studies in elite team handball; however, aerobic and jumping performance as well as anthropometric parameters (body weight and