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Kate M. Sansum, Max E. Weston, Bert Bond, Emma J. Cockcroft, Amy O’Connor, Owen W. Tomlinson, Craig A. Williams and Alan R. Barker

Maximal oxygen uptake ( V ˙ O 2 max ), typically expressed in relation to a measure of body size, is the “gold-standard” measure of cardiorespiratory fitness (CRF) ( 10 ). A valid measurement of V ˙ O 2 max is important in children and adolescents because a high CRF in youth is associated with a

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Hazzaa M. Al-Hazzaa and Mohammed A. Sulaiman

The present study examined the relationship between maximal oxygen uptake (V̇O2max) and daily physical activity in a group of 7- to 12-year-old boys. V̇O2max was assessed through the incremental treadmill test using an open circuit system. Physical activity level was obtained from heart rate telemetry outside of school time for 8 hrs during weekdays and during 40 min of physical education classes. The findings indicated that the absolute value of V̇O2max increased with age, while relative to body weight it remained almost the same across age, with a mean of 48.4 ml · kg−1 · min−1. Moreover, heart rate telemetry showed that the boys spent a limited amount of time on activities that raise the heart rate to a level above 160 bpm (an average of 1.9%). In addition, V̇O2max was found to be significantly related to the percentage of time spent at activity levels at or above a heart rate of 140 bpm, but not with activity levels at or above a heart rate of 160 bpm.

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James S. Hogg, James G. Hopker and Alexis R. Mauger

Purpose:

The novel self-paced maximal-oxygen-uptake (VO2max) test (SPV) may be a more suitable alternative to traditional maximal tests for elite athletes due to the ability to self-regulate pace. This study aimed to examine whether the SPV can be administered on a motorized treadmill.

Methods:

Fourteen highly trained male distance runners performed a standard graded exercise test (GXT), an incline-based SPV (SPVincline), and a speed-based SPV (SPVspeed). The GXT included a plateau-verification stage. Both SPV protocols included 5 × 2-min stages (and a plateau-verification stage) and allowed for self-pacing based on fixed increments of rating of perceived exertion: 11, 13, 15, 17, and 20. The participants varied their speed and incline on the treadmill by moving between different marked zones in which the tester would then adjust the intensity.

Results:

There was no significant difference (P = .319, ES = 0.21) in the VO2max achieved in the SPVspeed (67.6 ± 3.6 mL · kg−1 · min−1, 95%CI = 65.6–69.7 mL · kg−1 · min−1) compared with that achieved in the GXT (68.6 ± 6.0 mL · kg−1 · min−1, 95%CI = 65.1–72.1 mL · kg−1 · min−1). Participants achieved a significantly higher VO2max in the SPVincline (70.6 ± 4.3 mL · kg−1 · min−1, 95%CI = 68.1–73.0 mL · kg−1 · min−1) than in either the GXT (P = .027, ES = 0.39) or SPVspeed (P = .001, ES = 0.76).

Conclusions:

The SPVspeed protocol produces VO2max values similar to those obtained in the GXT and may represent a more appropriate and athlete-friendly test that is more oriented toward the variable speed found in competitive sport.

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Katia Ferrar, Harrison Evans, Ashleigh Smith, Gaynor Parfitt and Roger Eston

Many equations to predict maximal oxygen uptake (V̇O2max) from submaximal exercise tests have been proposed for young people, but the composition and accuracy of these equations vary greatly. The purpose of this systematic review was to analyze all submaximal exercise-based equations to predict V̇O2max measured via direct gas analysis for use with young people. Five databases were systematically searched in February 2013. Studies were included if they used a submaximal, exercise-based method to predict V̇O2max; the actual V̇O2max was gas analyzed; participants were younger than 18 years; and equations included at least one submaximal exercise-based variable. A meta-analysis and narrative synthesis were conducted. Sixteen studies were included. The mean equation validity statistic was strong, r = .786 (95% CI 0.747–0.819). Subgroup meta-analysis suggests exercise mode may contribute to the overall model, with running- and walking-based predictive equations reporting the highest mean r values (running r = .880; walking r = .821) and cycling the weakest (r = .743). Selection of the most appropriate equation should be guided by factors such as purpose, logistic limitations, appropriateness of the validation sample, the level of study bias, and the degree of accuracy. Suggestions regarding the most accurate equation for each exercise mode are provided.

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Zhen-Bo Cao, Nobuyuki Miyatake, Tomoko Aoyama, Mitsuru Higuchi and Izumi Tabata

Background:

The purpose was to develop new maximal oxygen uptake (VO2max) prediction models using a perceptually regulated 3-minute walk test.

Methods:

VO2max was measured with a maximal incremental cycle test in 283 Japanese adults. A 3-minute walk test was conducted at a self-regulated intensity corresponding to ratings of perceived exertion (RPE) 13.

Results:

A 3-minute walk distance (3MWD) was significantly related to VO2max (r = .60, P < .001). Three prediction models were developed by multiple regression to estimate VO2max using data on gender, age, 3MWD, and either BMI [BMI model, multiple correlation coefficients (R) = .78, standard error of estimate (SEE) = 5.26 ml⋅kg-1⋅min-1], waist circumference (WC model, R = .80, SEE = 5.04 ml⋅kg-1⋅min-1), or body fat percentage (%Fat model, R = .84, SEE = 4.57 ml⋅kg-1⋅min-1), suggesting that the %Fat model is the best model [VO2max = 37.501 + 0.463 × Gender (0 = women, 1 = men) – 0.195 × Age – 0.589 × %Fat + 0.053 × 3MWD]. Cross-validation by using the predicted residual sum of squares (PRESS) procedures demonstrated a high level of cross-validity of all prediction models.

Conclusions:

The new VO2max prediction models are reasonably applicable to estimating VO2max in Japanese adults and represent a quick, low-risk, and convenient means for estimating VO2max in the field.

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Katherine E. Robben, David C. Poole and Craig A. Harms

A two-test protocol (incremental/ramp (IWT) + supramaximal constant-load (CWR)) to affirm max and obviate reliance on secondary criteria has only been validated in highly fit children. In girls (n = 15) and boys (n = 12) with a wide range of VO2max (17–47 ml/kg/min), we hypothesized that this procedure would evince a VO2-WR plateau and unambiguous VO2max even in the presence of expiratory flow limitation (EFL). A plateau in the VO2-work rate relationship occurred in 75% of subjects irrespective of EFL There was a range in RER at max exercise for girls (0.97–1.14; mean 1.06 ± 0.04) and boys (0.98−1.09; mean 1.03 ± 0.03) such that 3/15 girls and 2/12 boys did not achieve the criterion RER. Moreover, in girls with RER > 1.0 it would have been possible to achieve this criterion at 78% VO2max. Boys achieved 92% VO2max at RER = 1.0. This was true also for HRmax where 8/15 girls’ and 6/12 boys’ VO2max would have been rejected based on HRmax being < 90% of age-predicted HRmax. In those who achieved the HRmax criterion, it represented a VO2 of 86% (girls) and 87% (boys) VO2max. We conclude that this two-test protocol confirms VO2max in children across a threefold range of VO2max irrespective of EFL and circumvents reliance on secondary criteria.

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Michael J. Buono, Julia J. Roby, Frank G. Micale and James F. Sallis

The Astrand-Ryhming est was modified to overcome problems of predicting V̇O2max in children. V̇O2max was measured directly during a maximal treadmill test and estimated by means of a submaximal protocol in a test group of 51 subjects ages 10–18 years. A multiple regression equation was developed with directly measured V̇O2max as the dependent variable and age, body weight, and V̇O2max estimated from the Astrand nomogram as independent variables. The validity and reliability of this equation to predict V̇O2max in children and adolescents was cross-validated. No significant difference was found between the measured V̇O2max and that estimated from the equation. The correlation coefficient between measured and estimated V̇O2max for the cross-validation group was 0.89, with a standard error of estimate of 12%. Test-retest reliability was 0.95. It was concluded that this modification of the Astrand nomogram provides a valid and reliable prediction of V̇O2max in children and adolescents.

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Volker Scheer, Tanja I. Janssen, Solveig Vieluf and Hans-Christian Heitkamp

and exercise testing strategies to predict performance and improve training concepts and competition results. Values that are classically used to predict running performance include maximal oxygen uptake (VO 2 max), percentage of VO 2 max, ventilatory and lactate thresholds, and running economy. 1

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Vanessa Martínez-Lagunas and Ulrich Hartmann

Purpose:

To evaluate the validity of the Yo-Yo Intermittent Recovery Test Level 1 (YYIR1) for the direct assessment and the indirect estimation of maximal oxygen consumption (VO2max) in female soccer players compared with a maximal laboratory treadmill test (LTT).

Methods:

Eighteen female soccer players (21.5 ± 3.4 y, 165.6 ± 7.5 cm, 63.3 ± 7.4 kg; mean ± SD) completed an LTT and a YYIR1 in random order (1 wk apart). Their VO2max was directly measured via portable spirometry during both tests and indirectly estimated from a published non-gender-specific formula (YYIR1-F1).

Results:

The measured VO2max values in LTT and YYIR1 were 55.0 ± 5.3 and 49.9 ± 4.9 mL · kg−1 · min−1, respectively, while the estimated VO2max values from YYIR1-F1 corresponded to 45.2 ± 3.4 mL · kg−1 · min−1. Large positive correlations between the VO2max values from YYIR1 and LTT (r = .83, P < .001, 90% confidence interval = .64–.92) and YYIR1-F1 and LTT (r = .67, P = .002, .37–.84) were found. However, the YYIR1 significantly underestimated players’ VO2max by 9.4% compared with LTT (P < .001) with Bland-Altman 95% limits of agreement ranging from –20.0% to 1.4%. A significant underestimation from the YYIR1-F1 (P < .001) was also identified (17.8% with Bland-Altman 95% limits of agreement ranging from –31.8% to –3.8%).

Conclusions:

The YYIR1 and YYIR1-F1 are not accurate methods for the direct assessment or indirect estimation of VO2max in female soccer players. The YYIR1-F1 lacks gender specificity, which might have been the reason for its larger error.