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Gustavo Monnerat, Alex S. Maior, Marcio Tannure, Lia K.F.C. Back and Caleb G.M. Santos

, VO 2 max, and recovery supported the possibility of genomic predictors affecting trainability. 7 – 11 However, few studies have examined the link between genetic factors within elite soccer players and their physiological and performance parameters. According to our hypothesis, using a complementary

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Benoit Capostagno and Andrew Bosch

This study examined the differences in fat and carbohydrate oxidation during running and cycling at the same relative exercise intensities, with intensity determined in a number of ways. Specifically, exercise intensity was expressed as a percentage of maximum workload (WLmax), maximum oxygen uptake (%VO2max), and maximum heart rate (%HRmax) and as rating of perceived exertion (RPE). Ten male triathletes performed maximal running and cycling trials and subsequently exercised at 60%, 65%, 70%, 75%, and 80% of their WLmax. VO2, HR, RPE, and plasma lactate concentrations were measured during all submaximal trials. Fat and carbohydrate oxidation were calculated from VO2 and VCO2 data. A 2-way ANOVA for repeated measures was used to determine any statistically significant differences between exercise modes. Fat oxidation was shown to be significantly higher in running than in cycling at the same relative intensities expressed as either %WLmax or %VO2max. Neither were there any significant differences in VO2max and HRmax between the 2 exercise modes, nor in submaximal VO2 or RPE between the exercise modes at the same %WLmax. However, heart rate and plasma lactate concentrations were significantly higher when cycling at 60% and 65% and 65–80%WLmax, respectively. In conclusion, fat oxidation is significantly higher during running than during cycling at the same relative intensity expressed as either %WLmax or %VO2max.

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Andrew M. Jones and Mark Burnley

The rate at which VO2 adjusts to the new energy demand following the onset of exercise strongly influences the magnitude of the “O2 defcit” incurred and thus the extent to which muscle and systemic homeostasis is perturbed. Moreover, during continuous high-intensity exercise, there is a progressive loss of muscle contractile efficiency, which is reflected in a “slow component” increase in VO2. The factors that dictate the characteristics of these fast and slow phases of the dynamic response of VO2 following a step change in energy turnover remain obscure. However, it is clear that these features of the VO2 kinetics have the potential to influence the rate of muscle fatigue development and, therefore, to affect sports performance. This commentary outlines the present state of knowledge on the characteristics of, and mechanistic bases to, the VO2 response to exercise of different intensities. Several interventions have been reported to speed the early VO2 kinetics and/or reduce the magnitude of the subsequent VO2 slow component, and the possibility that these might enhance exercise performance is discussed.

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Hervé Assadi and Romuald Lepers

Purposes:

To compare the physiological responses and maximal aerobic running velocity (MAV) during an incremental intermittent (45-s run/15-s rest) field test (45-15FIT) vs an incremental continuous treadmill test (TR) and to demonstrate that the MAV obtained during 45-15FIT (MAV45-15) was relevant to elicit a high percentage of maximal oxygen uptake (VO2max) during a 30-s/30-s intermittent training session.

Methods:

Oxygen uptake (VO2), heart rate (HR), and lactate concentration ([La]) were measured in 20 subjects during 2 maximal incremental tests and four 15-min intermittent tests. The time spent above 90% and 95% VO2max (t90% and t95% VO2max, respectively) was determined.

Results:

Maximal physiological parameters were similar during the 45-15FIT and TR tests (VO2max 58.6 ± 5.9 mL · kg−1 · min−1 for TR vs 58.5 ± 7.0 mL · kg−1 · min−1 for 45-15FIT; HRmax 200 ± 8 beats/min for TR vs 201 ± 7 beats/min for 45-15FIT). MAV45-15 was significantly (P < .001) greater than MAVTR (17.7 ± 1.1 vs 15.6 ± 1.4 km/h). t90% and t95% VO2max during the 30-s/30-s performed at MAVTR were significantly (P < .01) lower than during the 30-s/30-s performed at MAV45-15. Similar VO2 during intermittent tests performed at MAV45-15 and at MAVTR can be obtained by reducing the recovery time or using active recovery.

Conclusions:

The results suggested that the 45-15FIT is an accurate field test to determine VO2max and that MAV45-15 can be used during high-intensity intermittent training such as 30-s runs interspersed with 30-s rests (30-s/30-s) to elicit a high percentage of VO2max.

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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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Christopher D. Black and Patrick J. O’Connor

Ginger has known hypoalgesic and anti-inflammatory properties. The effects of an oral dose of ginger on quadriceps muscle pain, rating of perceived exertion (RPE), and recovery of oxygen consumption were examined during and after moderateintensity cycling exercise. Twenty-five college-age participants ingested a 2-g dose of ginger or placebo in a double-blind, crossover design and 30 min later completed 30 min of cycling at 60% of VO2peak. Quadriceps muscle pain, RPE, work rate, heart rate (HR), and oxygen uptake (VO2) were recorded every 5 min during exercise, and HR and VO2 were recorded for 20 min after exercise. Compared with placebo, ginger had no clinically meaningful or statistically significant effect on perceptions of muscle pain, RPE, work rate, HR, or VO2 during exercise. Recovery of VO2 and HR after the 30-min exercise bout followed a similar time course in the ginger and placebo conditions. The results were consistent with related findings showing that ingesting a large dose of aspirin does not acutely alter quadriceps muscle pain during cycling, and this suggests that prostaglandins do not play a large role in this type of exercise-induced skeletal-muscle pain. Ginger consumption has also been shown to improve VO2 recovery in an equine exercise model, but these results show that this is not the case in humans.

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Lieselot Decroix, Kevin De Pauw, Carl Foster and Romain Meeusen

Aim:

To review current cycling-related sport-science literature to formulate guidelines to classify female subject groups and to compare this classification system for female subject groups with the classification system for male subject groups.

Methods:

A database of 82 papers that described female subject groups containing information on preexperimental maximal cycle-protocol designs, terminology, biometrical and physiological parameters, and cycling experience was analyzed. Subject groups were divided into performance levels (PLs), according to the nomenclature. Body mass, body-mass index, maximal oxygen consumption (VO2max), peak power output (PPO), and training status were compared between PLs and between female and male PLs.

Results:

Five female PLs were defined, representing untrained, active, trained, well-trained, and professional female subjects. VO2max and PPO significantly increased with PL, except for PL3 and PL4 (P < .01). For each PL, significant differences were observed in absolute and relative VO2max and PPO between male and female subject groups. Relative VO2max is the most cited parameter for female subject groups and is proposed as the principal parameter to classify the groups.

Conclusion:

This systematic review shows the large variety in the description of female subject groups in the existing literature. The authors propose a standardized preexperimental testing protocol and guidelines to classify female subject groups into 5 PLs based on relative VO2max, relative PPO, training status, absolute VO2max, and absolute PPO.

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Michal Botek, Jakub Krejčí, Andrew J. McKune and Barbora Sládečková

in a heterogenous group of athletes. Methods Participants A total of 16 male athletes (mean [SD]; age 31.6 [8.6] y, body mass 71.5 [8.8] kg, body height 177.0 [7.2] kg, body fat 13.4% [4.4%], VO 2 max 57.2 [8.9] mL·kg −1 ·min −1 ) volunteered for this study. They followed instructions to avoid using

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Kerry McGawley and Hans-Christer Holmberg

Purpose:

Cross-country-ski races place complex demands on athletes, with events lasting between approximately 3 min and 2 h. The aim of the current study was to compare the aerobic and anaerobic measures derived from a short time trial (TT) between male and female skiers using diagonal cross-country skiing.

Methods:

Twenty-four highly trained cross-country skiers (12 male and 12 female, age 17.4 ± 1.4 y, body mass 68.2 ± 8.9 kg, height 174 ± 8 cm) participated. The submaximal VO2–speed relationship and VO2max were derived from an incremental ramp test to exhaustion (RAMP), while the accumulated oxygen deficit (AOD), peak VO2, and performance time were measured during a 600-m TT.

Results:

The female skiers took longer to complete the TT than the males (209 ± 9 s vs 166 ± 7 s, P < .001) and exhibited a lower relative anaerobic contribution (20% ± 4% vs 24% ± 3%, P = .015) and a higher fractional utilization of VO2max (84% ± 4% vs 79% ± 5%, P = .007) than males. Although there was no significant difference in AOD between the sexes (40.9 ± 9.5 and 47.3 ± 7.4 mL/kg for females and males, respectively; P = .079), the mean difference ± 90% confidence intervals of 6.4 ± 6.0 mL/kg reflected a likely practical difference (ES = 0.72). The peak VO2 during the TT was significantly higher than VO2max during the RAMP for all participants combined (62.3 ± 6.8 vs 60.5 ± 7.2 mL · kg−1 · min−1, P = .011), and the mean difference ± 90% confidence intervals of 1.8 ± 1.1 mL · kg−1 · min−1 reflected a possible practical difference (ES = 0.25).

Conclusions:

These results show that performance and physiological responses to a self-paced TT lasting approximately 3 min differ between sexes. In addition, a TT may provide a valid measure of VO2max.

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Katrina Taylor, Jeffrey Seegmiller and Chantal A. Vella

Purpose:

To determine whether a decremental protocol could elicit a higher maximal oxygen consumption (VO2max) than an incremental protocol in trained participants. A secondary aim was to examine whether cardiac-output (Q) and stroke-volume (SV) responses differed between decremental and incremental protocols in this sample.

Methods:

Nineteen runners/triathletes were randomized to either the decremental or incremental group. All participants completed an initial incremental VO2max test on a treadmill, followed by a verification phase. The incremental group completed 2 further incremental tests. The decremental group completed a second VO2max test using the decremental protocol, based on their verification phase. The decremental group then completed a final incremental test. During each test, VO2, ventilation, and heart rate were measured, and cardiac variables were estimated with thoracic bioimpedance. Repeated-measures analysis of variance was conducted with an alpha level set at .05.

Results:

There were no significant main effects for group (P = .37) or interaction (P = .10) over time (P = .45). VO2max was similar between the incremental (57.29 ± 8.94 mL · kg–1 · min–1) and decremental (60.82 ± 8.49 mL · kg–1 · min–1) groups over time. Furthermore, Q and SV were similar between the incremental (Q 22.72 ± 5.85 L/min, SV 119.64 ± 33.02 mL/beat) and decremental groups (Q 20.36 ± 4.59 L/min, SV 109.03 ± 24.27 mL/beat) across all 3 trials.

Conclusions:

The findings suggest that the decremental protocol does not elicit higher VO2max than an incremental protocol but may be used as an alternative protocol to measure VO2max in runners and triathletes.