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Jacinta M. Saldaris, Grant J. Landers and Brendan S. Lay

body mass 62.9 [7.8] kg, and VO 2peak 63.6 [4.4] mL·kg −1 ·min −1 ) participated in the study. Ethical approval was granted by the Human Research Ethics Office at the University of Western Australia (RA/4/1/8273). Informed written consent was obtained from all participants before their involvement in

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Livia Victorino Souza, Franciele De Meneck, Vanessa Oliveira, Elisa Mieko Higa, Eliana Hiromi Akamine and Maria do Carmo Franco

recorded and used to calculate the VO 2 max (mL/kg/min) according to the equation proposed by Leger and Lambert ( 23 ) and validated for children and adolescents ( 24 ). Blood Pressure Evaluation Blood pressure was evaluated according Fourth National Task Force on High Blood Pressure in Children and

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Trent Stellingwerff, Ingvill Måkestad Bovim and Jamie Whitfield

 = phosphocreatine; PRO = protein; RFD = rate of force development; suppl. = supplementation; SV = stroke volume; VO 2 max = maximal oxygen consumption. Middle-distance race intensity is extreme, with 800- to 5,000-m races being at ∼95% to 130% of VO 2 max ( Duffield et al., 2005 ), or 75–85% of maximum sprint speed

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Twan ten Haaf, Selma van Staveren, Danilo Iannetta, Bart Roelands, Romain Meeusen, Maria F. Piacentini, Carl Foster, Leo Koenderman, Hein A.M. Daanen and Jos J. de Koning

index, 23.5 [2.1] kg/m 2 ; and VO 2max at baseline, 51.8 [6.3] mL/kg/min). Subjects were categorized in performance levels 1 (4%), 2 (57%), 3 (25%), and 4 (14%) according to VO 2max -based athlete classification norms. 10 , 11 Subjects gave written informed consent prior to the first measurements. The

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Gregory B. Dwyer and Anthony D. Mahon

Little is known about the responses to graded exercise in athletes with cerebral palsy (CP). This study compared the ventilatory threshold (VT) and peak VO2 among athletes with CP during treadmill and cycle ergometry exercise. Six (4 men, 2 women) track athletes with CP volunteered to participate in the study. Graded exercise tests on a treadmill and cycle ergometer were performed on separate days to assess VT and peak VO2. Paired t tests were used to compare the two exercise modes. The VT, expressed as a percentage of peak VO2, was significantly higher on the cycle ergometer than on the treadmill. The absolute VO2 at the VT was similar during both testing modes, and peak VO2 was significantly higher on the treadmill than on the cycle ergometer. Similar to responses seen in able-bodied individuals, the VO2 at VT was similar during both modes of exercise, while the peak VO2 was 10% lower on the cycle than on the treadmill. Cycle ergometer peak VO2 in these athletes was higher than previous reports of individuals with CP for the cycle ergometer.

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Timothy R. McConnell, Jean H. Haas and Nancy C. Conlin

Thirty-eight children (mean age 12.2 ±3.6 yrs) were tested to (a) compare the training heart rate (HR) and oxygen uptake (V̇O2) computed from commonly used exercise prescription methods to the heart rate (HRAT) and V̇O2 (ATge) at the gas exchange anaerobic threshold, (b) compute the range of relative HRs and V̇O2s (% HRmax and % V̇O2max, respectively) at which the ATge occurred, and (c) discuss the implications for prescribing exercise intensity. The ATge occurred at a V̇O2 of 20.9 ml · kg−1 · min−1 and an HR of 129 beats·min−1. The training HR and V̇O2 computed using 70 and 85% HRmax, 70% of the maximal heart rate reserve (HRR), and 57 and 78% V·O2max, were significantly different (p<.05) from their corresponding ATge values. To compute training % HRmax, % V̇O2max, and % HRR values that would not significantly differ from the ATge, then 68% HRmax, 48% V̇O2max, and 41% HRR would need to be used for the current population.

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Han C.G. Kemper and Lando L.J. Koppes

The purpose of this study was to test the hypothesis that physical activity (PA), measured over a period of 23 years, is beneficial to aerobic fitness (VO2max) in boys and girls (13-36 years) who were enrolled in the Amsterdam Growth and Health Longitudinal Study (AGAHLS). PA was measured using a standardized activity interview. VO2max was assessed directly with a maximal running test on a treadmill. To assess the longitudinal relationship between PA and VO2max, different longitudinal analyses were carried out over different age periods, correcting for various confounders such as lifestyle parameters, biological parameters, and initial VO2max. Highly significant relationships (p < .05) were observed between PA and VO2max in four of the five analyses. However, in an autoregression analysis, when current PA has been related to the future change in VO2max, the results are not any more significant (p > .05). Analysis of the data of PA and VO2max from the AGAHLS population does not fully support the hypothesis that PA affects VO2max.

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Michelle S.M. Silva, Wladimir Bolani, Cleber R. Alves, Diogo G. Biagi, José R. Lemos Jr, Jeferson L. da Silva, Patrícia A. de Oliveira, Guilherme B. Alves, Edilamar M. de Oliveira, Carlos E. Negrão, José E. Krieger, Rodrigo G. Dias and Alexandre C. Pereira

Aim:

To study the relationship between the ACTN3 R577X polymorphism and oxygen uptake (VO2) before and after exercise training.

Methods:

Police recruits (N = 206, 25 ± 4 y) with RR (n = 75), RX (n = 97), and XX (n = 33) genotypes were selected. After baseline measures, they underwent 18 wk of running endurance training. Peak VO2 was obtained by cardiopulmonary exercise testing.

Results:

Baseline body weight was not different among genotypes. At baseline, XX individuals displayed higher VO2 at anaerobic threshold, respiratory compensation point, and exercise peak than did RR individuals (P < .003). Endurance training significantly increased VO2 at anaerobic threshold, respiratory compensation point, and exercise peak (P < 2 × 10−6), but the differences between XX and RR were no longer observed. Only relative peak VO2 exercise remained higher in XX than in RR genotype (P = .04). In contrast, the increase in relative peak VO2 was greater in RR than in XX individuals (12% vs 6%; P = .02).

Conclusion:

ACTN3 R577X polymorphism is associated with VO2. XX individuals have greater aerobic capacity. Endurance training eliminates differences in peak VO2 between XX and RR individuals. These findings suggest a ceiling-effect phenomenon, and, perhaps, trained individuals may not constitute an adequate population to explain associations between phenotypic variability and gene variations.

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Stanley P. Brown, Joel C. Jordan, Linda F. Chitwood, Kim R. Beason, John G. Alvarez and Kendal P. Honea

This study was performed to investigate the relationship between heart rate (HR) as a percentage of peak HR and oxygen uptake (V̇O2) as a percentage of peak V̇O2 in older adults while performing deep water running (DWR). Twenty-three (14 male and 9 female) apparently healthy older adults, age 50 to 70 years, volunteered. Deep water running to V̇O2peak was performed in 3-min stages at leg speeds controlled by a metronome beginning at 60 strides per minute and increasing 12 strides per minute each additional stage. Oxygen uptake and HR were continuously monitored by open-circuit spirometry and radiotelemetry, respectively. Simple linear regression analysis was used to establish the relationship between the physiological variables. The relationship between %V̇O2peak and %HRpeak was statistically significant, with the male (%V̇O2peak = 1.5301 [%HRpeak] − 54.4932 [r = .96, SEE = 6.0%]) and female (%V̇O2peak = 1.5904 [%HRpeak] - 62.3935 [r = .91, SEE = 6.9%]) regression equations being significantly different (p < .05). The regression equations of older adults and those for college-aged males (%VO2peak = 1.4634 [%HRpeak] − 49.619) and females (%V̇O2peak = 1.6649 [%HRpeak] − 67.862) were not significantly different.

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Katrin A. Dias, Concetta E Masterson, Matthew P. Wallen, Arnt E. Tjonna, Mansoureh S. Hosseini, Peter S.W. Davies, Peter A. Cain, Gary M. Leong, Ross Arena, Charlotte B. Ingul and Jeff S. Coombes

Purpose:

Poor cardiorespiratory fitness is associated with increased all cause morbidity and mortality. In children with obesity, maximum oxygen uptake (V̇O2max) may not be achieved due to reduced motivation and peripheral fatigue. We aimed to identify a valid submaximal surrogate for V̇O2max in children with obesity.

Method:

Ninety-two children with obesity (7–16 years) completed a maximal exercise treadmill test and entered a three-month exercise and/or nutrition intervention after which the exercise test was repeated (n = 63). Participants were required to reach V̇O2max to be included in this analysis (n = 32 at baseline and n = 13 at both time-points). The oxygen uptake efficiency slope (OUES) was determined as the slope of the line when V̇O2 (L/min) was plotted against log V̇E. Associations between the maximal OUES, submaximal OUES (at 3, 4, 5 and 6 min of the exercise test) and V̇O2max were calculated.

Results:

In the cross-sectional analysis, V̇O2max (L/min) was strongly correlated with 5-min OUES independent of Tanner puberty stage and sex (R 2 = .80, p < .001). Longitudinal changes in V̇O2max were closely reflected by changes in 5-min OUES independent of change in percent body fat (R 2 = .63, p < .05).

Conclusion:

The 5-min OUES is a viable alternative to V̇O2max when assessing children with obesity.