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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.

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Denis M. Pelletier, Guillaume Lacerte and Eric D.B. Goulet

Lately, the effect of quercetin supplementation (QS) on endurance performance (EP) and maximal oxygen consumption (VO2max) has been receiving much scientific and media attention. Therefore, a meta-analysis was performed to determine QS’s ergogenic value on these variables. Studies were located with database searches (PubMed and SPORTDiscus) and cross-referencing. Outcomes represent mean percentage changes in EP (measured via power output) and VO2max between QS and placebo. Random-effects model meta-regression, mixed-effects model analog to the ANOVA, random-effects weighted mean effect summary, and magnitudebased inferences analyses were used to delineate the effects of QS. Seven research articles (representing 288 subjects) were included, producing 4 VO2max and 10 EP effect estimates. Mean QS daily intake and duration were, respectively, 960 ± 127 mg and 26 ± 24 d for the EP outcome and 1,000 ± 0 mg and 8 ± 23 d for the VO2max outcome. EP was assessed during exercise with a mean duration of 79 ± 82 min. Overall, QS improved EP by 0.74% (95% CI: 0.10–1.39, p = .02) compared with placebo. However, only in untrained individuals (0.83% ± 0.78%, p = .02) did QS significantly improve EP (trained individuals: 0.09% ± 2.15%, p = .92). There was no relationship between QS duration and EP (p = .69). Overall, QS increased VO2max by 1.94% (95% CI: 0.30–3.59, p = .02). Magnitude-based inferences suggest that the effect of QS on EP and VO2max is likely to be trivial for both trained and untrained individuals. In conclusion, this meta-analysis indicates that QS is unlikely to prove ergogenic for aerobic-oriented exercises in trained and untrained individuals.

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Vinícius F. Milanez, Rafael E. Pedro, Alexandre Moreira, Daniel A. Boullosa, Fuad Salle-Neto and Fábio Y. Nakamura

Purpose:

The aim of this study was to verify the influence of aerobic fitness (VO2max) on internal training loads, as measured by the session rating of perceived exertion (session-RPE) method.

Methods:

Nine male professional outfeld futsal players were monitored for 4 wk of the in-season period with regards to the weekly accumulated session-RPE, while participating in the same training sessions. Single-session-RPE was obtained from the product of a 10-point RPE scale and the duration of exercise. Maximal oxygen consumption was determined during an incremental treadmill test.

Results:

The average training load throughout the 4 wk period varied between 2,876 and 5,035 arbitrary units. Technical-tactical sessions were the predominant source of loading. There was a significant correlation between VO2max (59.6 ± 2.5 mL·kg–1 ·min–1) and overall training load accumulated over the total period (r = –0.75).

Conclusions:

The VO2max plays a key role in determining the magnitude of an individual’s perceived exertion during futsal training sessions.

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Georges Jabbour, Melanie Henderson, Angelo Tremblay and Marie Eve Mathieu

Objective:

Moderate-to-vigorous physical activity (MVPA) improves aerobic fitness in children, which is usually assessed by maximal oxygen consumption. However, other indices of aerobic fitness have been understudied.

Methods:

To compare net oxygen (VO2net), net energy consumption (Enet), net mechanical efficiency (MEnet), and lipid oxidation rate in active and inactive children across body weight statuses.

Design:

The sample included normal-weight, overweight, and obese children of whom 44 are active (≥30 min of MVPA/d) and 41 are inactive (<30 min of MVPA/d). VO2net, Enet, MEnet and lipid oxidation rate were determined during an incremental maximal cycling test.

Results:

Active obese participants had significantly lower values of VO2net and Enet and higher MEnet than inactive obese participants at all load stages. In addition, active obese participants showed a significantly higher lipid oxidation rate compared with inactive obese and active overweight and normal-weight participants. VO2net, Enet, and MEnet were similar across active children, regardless of body weight status.

Conclusion:

Thirty minutes or more of MVPA per day is associated with a potentiation of aerobic fitness indicators in obese prepubertal children. Moreover, the indices of aerobic fitness of inactive obese children are significantly different from those of active obese and nonobese ones.

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Laura K. Fewell, Riley Nickols, Amanda Schlitzer Tierney and Cheri A. Levinson

: maximal oxygen consumption, vertical jump, grip strength, and push-ups. Body mass index was also obtained at admission and discharge. This study was approved by the Institutional Review Board at Washington University in St. Louis prior to data collection. Physical Outcome Measures Body Mass Index (BMI

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Michael E. Hales and John D. Johnson II

), biceps femoris (BF), gastrocnemius medial head, and tibialis anterior (TA); and cardiopulmonary factors: maximal oxygen consumption (VO 2 max), heart rate (HR), respiratory exchange ratio (RER), metabolic equivalent of task (MET), and energy expenditure. The test course (20 × 20 m 2 area) consisted of 8

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Lara A. Carlson, Kaylee M. Pobocik, Michael A. Lawrence, Daniel A. Brazeau and Alexander J. Koch

levels would be higher following AMEX than PMEX. Methods Participants A total of 12 healthy male runners (age: 20.75 [0.62] y, height: 1.75 [0.04] m, mass: 73.63 [10.43] kg, and maximal oxygen consumption [VO 2 max]: 57.72 [6.11] mL/kg/min) with a minimum VO 2 max of 50 mL/kg/min and not supplementing

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Amelia J. Carr, Laura A. Garvican-Lewis, Brent S. Vallance, Andrew P. Drake, Philo U. Saunders, Clare E. Humberstone and Christopher J. Gore

availability results in decreased inspired partial pressure of oxygen (PiO 2 ), and a subsequent decreased arterial oxygen partial pressure (PaO 2 ) and arterial oxygen saturation (SaO 2 ), contributing to a reduced maximal oxygen consumption (VO 2 max). 8 A further response to reduced PiO 2 is an increased

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Elin Ekblom-Bak, Örjan Ekblom, Gunnar Andersson, Peter Wallin and Björn Ekblom

, together with additional PA outside school hours, on adult PA level, maximal oxygen consumption (VO 2max ), and perceived and metabolic health later in life in a large sample of Swedish men and women of a broad age span. Methods From October 1982 to September 2015, 363,746 men and women, aged 19

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Ryan P. Durk, Esperanza Castillo, Leticia Márquez-Magaña, Gregory J. Grosicki, Nicole D. Bolter, C. Matthew Lee and James R. Bagley

the best of our knowledge, no study has examined if F/B is associated with cardiorespiratory fitness, as assessed by maximal oxygen consumption (VO 2 max), independent from dietary or anthropometric measures. The purpose of this exploratory study was to identify potential relationships among relative