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Daisuke Kume, Akira Iguchi and Hiroshi Endoh

oxygenation profiles measured with NIRS provide valuable information for the understanding of physiological response in active muscles during exercise and their relationship with physical performance. The 20-m shuttle run test (20mSRT) is the most common field test for assessing aerobic fitness in many

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Grant R. Tomkinson, Justin J. Lang, Joel Blanchard, Luc A. Léger and Mark S. Tremblay

), and later moving into progressive exercise shuttle run tests ( 68 ). More recently, the 20-m shuttle run test (20mSRT), also called the “beep” test or the Progressive Aerobic Cardiovascular Endurance Run test, has been identified as probably the most widely used field test of CRF among children and

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Bo Fernhall, A. Lynn Millar, Kenneth H. Pitetti, Terri Hensen and Mathew D. Vukovsch

We cross validated the 20-m shuttle run test of aerobic capacity in children and adolescents with mild and moderate mental retardation (MR) using the population specific formula of Fernhall et al. (1998). Nine boys and 8 girls (age = 13.7 yr) completed a maximal treadmill protocol (measured V̇O2peak) and a 20-m shuttle run (predicted V̇O2peak). The measured peak oxygen consumption (V̇O2peak) was 39.4 ml kg-1 min-1. The relationship between measured and predicted V̇O2peak was r = .86 with an SEE of 6.2 ml kg-1 min-1. Multiple regression and Bland-Altman analyses showed that there was little bias, but the Bland-Altman analysis indicated highly variable limits of agreement (Bland & Altman 1986). Thus, the traditional approach (regression analysis) to concurrent validity revealed that the 20-m shuttle run is a valid indicator of V̇O2peak in these participants. The accuracy of prediction (Bland & Altman, 1986), however, was lower than expected in a population without MR.

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Akira Matsuzaka, Yuko Takahashi, Masayuki Yamazoe, Naomi Kumakura, Akiko Ikeda, Boguslaw Wilk and Oded Bar-Or

The purpose of this study was to examine the validity of a 20-m shuttle-run test as an aerobic fitness test for Japanese children, adolescents, and young adults. Participants were 62 boys and 70 girls aged 8–17 years and 56 men and 99 women aged 18–23 years. Stepwise regression analysis was used to elucidate the relationship between shuttle-run performance, age, gender, and anthropometric parameters (as independent variables) and peak oxygen uptake (VO2peak), determined directly on a treadmill, as a dependent variable. We observed high multiple correlations for adults (R 2 = .88) and for children and adolescents (R 2 = .80). Therefore, it is suggested that our multiple regression equations are more appropriate for predicting VO2peak in Japanese children, adolescents, and adults.

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Martin Buchheit, Bachar Haydar, Karim Hader, Pierre Ufland and Said Ahmaidi

Purpose:

To examine physiological responses to submaximal feld running with changes of direction (COD), and to compare two approaches to assess running economy (RE) with COD, ie, during square-wave (SW) and incremental (INC) exercises.

Methods:

Ten male team-sport athletes performed, in straight-line or over 20 m shuttles, one maximal INC and four submaximal SW (45, 60, 75 and 90% of the velocity associated with maximal pulmonary O2 uptake [vVO2pmax]). Pulmonary (VO2p) and gastrocnemius (VO2m) O2 uptake were computed for all tests. For both running mode, RE was estimated as the O2 cost per kilogram of bodyweight, per meter of running during all SW and INC.

Results:

Compared with straight-line runs, shuttle runs were associated with higher VO2p (eg, 33 ± 6 vs 37 ± 5 mL O2·min–1·kg–1 at 60%, P < .01) and VO2m (eg, 1.1 ± 0.5 vs 1.3 ± 0.8 mL O2·min–1·100 g–1 at 60%, P = .18, Cohen’s d = 0.32). With COD, RE was impaired during SW (0.26 ± 0.02 vs 0.24 ± 0.03 mL O2·kg–1·m–1, P < .01) and INC (0.23 ± 0.04 vs 0.16 ± 0.03 mL O2·kg–1·m–1, P < .001). For both SW and INC tests, the changes in RE with COD were related to height (eg, r = .56 [90%CL, 0.01;0.85] for SW) and weekly training/competitive volume (eg, r = –0.58 [–0.86;–0.04] for SW). For both running modes, RE calculated from INC was better than that from SW (both P < .001).

Conclusion:

Although RE is impaired during feld running with COD, team-sport players of shorter stature and/or presenting greater training/competitive volumes may present a lower RE deterioration with COD. Present results do not support the use of INC to assess RE in the feld, irrespective of running mode.

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Stamatis Agiovlasitis, Kenneth H. Pitetti, Myriam Guerra and Bo Fernhall

This study examined whether 20-m shuttle-run performance, sex, body mass index (BMI), age, height, and weight are associated with peak oxygen uptake (VO2peak) in youth with Down syndrome (DS; n = 53; 25 women, age 8–20 years) and whether these variables can be used to develop an equation to predict VO2peak. BMI, 20-m shuttle-run performance, and sex were significantly associated with VO2peak in youth with DS, whereas age, height, and weight were not. A regression model included only shuttle-run performance as a significant predictor of VO2peak; however, the developed prediction equation had low individual predictability. Therefore, 20-m shuttle-run performance alone does not provide valid prediction of VO2peak in youth with DS. Sex, BMI, age, height, and weight do not improve the prediction of VO2peak.

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Michael W. Beets and Kenneth H. Pitetti

This study was undertaken to initiate a standardized methodology model for reporting cardiovascular fitness (CVF) for youths in the US and to compare the CVF of youths from a Midwestern metropolitan area to their international and US peers. Participants were 795 youths 8–18 yrs old. The 20-m shuttle-run test (20MST) was used to determine CVF and body composition was determined by body mass index (BMI). Comparative analysis was made by sex and age. Participants in this study showed similar CVF levels with their US peers, but when compared with their international counterparts, they demonstrated considerably lower CVF and higher BMI.

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Kenneth H. Pitetti, Bo Fernhall and Steve Figoni

Two regression equations were developed to predict cardiovascular fitness (CVF) based on the 20-m shuttle run test (20-MST) for nondisabled youth and for youth with mild mental retardation (MR). The purpose of this study was to compare the validity of both regression formulas to predict CVF in nondisabled, healthy youths (ages 8 to 15 yrs; 38 females and 13 males). Participants performed two modified Bruce protocol treadmill (TM) tests and two 20-MSTs on separate days. CVF (V̇O2peak, ml • kg−1 • min−1) was measured during the TM tests and computed for the 20-MST using both regression equations. Results indicate that test-retest correlations for the 20-MST (# of laps; r = 0.89) and TM test (V̇O2peak, ml • kg−1 • min−1; r = 0.86) were high. Predicted V̇O2peak values were moderately significant (nondisabled youth: r = 0.55, p < .01; youth with MR: r = 0.66, p < .01) when compared with TM V̇O2peak. Correlation between the two regression equations was significant (r = 0.78, p < .01).

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Matthew T. Mahar, Gregory J. Welk, David A. Rowe, Dana J. Crotts and Kerry L. McIver

Background:

The purpose of this study was to develop and cross-validate a regression model to estimate VO2peak from PACER performance in 12- to 14-year-old males and females.

Methods:

A sample of 135 participants had VO2peak measured during a maximal treadmill test and completed the PACER 20-m shuttle run. The sample was randomly split into validation (n = 90) and cross-validation (n = 45) samples. The validation sample was used to develop the regression equation to estimate VO2peak from PACER laps, gender, and body mass.

Results:

The multiple correlation (R) was .66 and standard error of estimate (SEE) was 6.38 ml·kg−1·min−1. Accuracy of the model was confirmed on the cross-validation sample. The regression equation developed on the total sample was: VO2peak = 47.438 + (PACER*0.142) + (Gender[m=1, f=0]*5.134) − (body mass [kg]*0.197), R = .65, SEE = 6.38 ml·kg–1·min–1.

Conclusions:

The model developed in this study was more accurate than the Leger et al. model and allows easy conversion of PACER laps to VO2peak.

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Gregory S. Anderson

The purpose of this study was to determine the validity of using the 1600-m distance run (DR) and the maximal multistage 20-m shuttle run (SR) as predictors of aerobic capacity in active boys 10 to 12 years of age. The influence of weight and maximal sprint running speed on test performance scores were also investigated. Both the DR and SR were found to have concurrent validity in the group studied, correlated to a directly measured VO2max (ml kg−1·min−1) determined through a progressive bicycle ergometer test. However, predicted VO2max values using SR results differed significantly from measured values. Weight was not found to be significantly correlated with either of the predictive methods, whereas maximal sprint running speed, as measured through a 40-m dash, was found to correlate significantly with the results of both the DR and SR. These results suggest that the combined influence of running efficiency and anaerobic energy production significantly influence the performance of both predictive methods.