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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.

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Andrea J. Braakhuis, Kelly Meredith, Gregory R. Cox, William G. Hopkins and Louise M. Burke

A routine activity for a sports dietitian is to estimate energy and nutrient intake from an athlete’s self-reported food intake. Decisions made by the dietitian when coding a food record are a source of variability in the data. The aim of the present study was to determine the variability in estimation of the daily energy and key nutrient intakes of elite athletes, when experienced coders analyzed the same food record using the same database and software package. Seven-day food records from a dietary survey of athletes in the 1996 Australian Olympic team were randomly selected to provide 13 sets of records, each set representing the self-reported food intake of an endurance, team, weight restricted, and sprint/power athlete. Each set was coded by 3–5 members of Sports Dietitians Australia, making a total of 52 athletes, 53 dietitians, and 1456 athlete-days of data. We estimated within- and between- athlete and dietitian variances for each dietary nutrient using mixed modeling, and we combined the variances to express variability as a coefficient of variation (typical variation as a percent of the mean). Variability in the mean of 7-day estimates of a nutrient was 2- to 3-fold less than that of a single day. The variability contributed by the coder was less than the true athlete variability for a 1-day record but was of similar magnitude for a 7-day record. The most variable nutrients (e.g., vitamin C, vitamin A, cholesterol) had ~3-fold more variability than least variable nutrients (e.g., energy, carbohydrate, magnesium). These athlete and coder variabilities need to be taken into account in dietary assessment of athletes for counseling and research.

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Thiago Oliveira Borges, Nicola Bullock, David Aitken and Aaron J. Coutts

Methods:

This study compared 3 commercially available ergometers for within- and between-brands difference to a first-principle calibration rig.

Results:

All ergometers underestimated true mean power, with errors of 27.6% ± 3.7%, 4.5% ± 3.5%, and 22.5% ± 1.9% for the KayakPro, WEBA, and Dansprint, respectively. Within-brand ergometer power differences ranged from 17 ± 9 to 22 ± 11 W for the KayakPro, 3 ± 4 to 4 ± 4 W for the WEBA, and 5 ± 3 to 5 ± 4 W for the Dansprint. The linear-regression analysis showed that most kayak ergometers have a stable coefficient of variation (0.9–1.7%) with a moderate effect size.

Conclusion:

Taken collectively, these findings show that different ergometers present inconsistent outcomes. Therefore, we suggest that athlete testing be conducted on the same ergometer brand, preferably the same ergometer. Optimally, that ergometer should be calibrated using a first-principle device before any athlete testing block.

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Corrado Lupo, Laura Capranica and Antonio Tessitore

Context:

The assessment of internal training load (ITL) using the session rating of perceived exertion (session RPE) has been demonstrated to provide valuable information, also in team sports. Nevertheless, no studies have investigated the use of this method during youth water polo training.

Purpose:

To evaluate youth water polo training, showing the corresponding level of reliability of the session-RPE method.

Methods:

Thirteen male youth water polo players (age 15.6 ± 0.5 y, height 1.80 ± 0.06 m, body mass 72.7 ± 7.8 kg) were monitored during 8 training sessions (80 individual training sessions) over 10 d. The Edwards summated heart-rate-zone method was used as a reference measure of ITL; the session-RPE rating was obtained using CR-10 scale modified by Foster. The Pearson product–moment was applied to regress the Edwards heart-rate-zone method against CR-10 session RPE for each training session and individual data.

Results:

Analyses reported overall high (r = .88, R 2 = .78) and significant (P < .001) correlations between the Edwards heart-rate and session-RPE methods. Significant correlations were also shown for each training session (r range .69–.92, R 2 range .48–.85, P < .05) and individual data (r range .76–.98, R 2 range .58–.97, P < .05).

Discussion:

The results confirmed that the session-RPE method as an easy and reliable tool to evaluate ITL in youth water polo, allowing coaches to efficiently monitor their training plans.

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Laurent Mourot, Nicolas Fabre, Aldo Savoldelli and Federico Schena

To determine the most accurate method based on spectral analysis of heart-rate variability (SA-HRV) during an incremental and continuous maximal test involving the upper body, the authors tested 4 different methods to obtain the heart rate (HR) at the second ventilatory threshold (VT2). Sixteen ski mountaineers (mean ± SD; age 25 ± 3 y, height 177 ± 8 cm, mass 69 ± 10 kg) performed a roller-ski test on a treadmill. Respiratory variables and HR were continuously recorded, and the 4 SA-HRV methods were compared with the gas-exchange method through Bland and Altman analyses. The best method was the one based on a time-varying spectral analysis with high frequency ranging from 0.15 Hz to a cutoff point relative to the individual’s respiratory sinus arrhythmia. The HR values were significantly correlated (r 2 = .903), with a mean HR difference with the respiratory method of 0.1 ± 3.0 beats/min and low limits of agreements (around –6/+6 beats/min). The 3 other methods led to larger errors and lower agreements (up to 5 beats/min and around –23/+20 beats/min). It is possible to accurately determine VT2 with an HR monitor during an incremental test involving the upper body if the appropriate HRV method is used.

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Anthony N. Turner, Conor Buttigieg, Geoff Marshall, Angelo Noto, James Phillips and Liam Kilduff

Session rating of perceived exertion (sRPE) is known to significantly relate to heart-rate (HR) -based methods of quantifying internal training load (TL) in a variety of sports. However, to date this has not been investigated in fencing and was therefore the aim of this study. TL was calculated by multiplying the sRPE with exercise duration and through HR-based methods calculated using Banister and Edwards TRIMP. Seven male elite foil fencers (mean ± SD age 22.3 ± 1.6 y, height 181.3 ± 6.5 cm, body mass 77.7 ± 7.6 kg) were monitored over the period of 1 competitive season. The sRPE and HR of 67 training sessions and 3 competitions (87 poule bouts and 12 knockout rounds) were recorded and analyzed. Correlation analysis was used to determine any relationships between sRPE- and HR-based methods, accounting for individual variation, mode of training (footwork drills vs sparring sessions), and stage of competition (poules vs knockouts). Across 2 footwork sessions, sRPE and Banister and Edwards TRIMP were found to be reliable, with coefficient of variation values of 6.0%, 5.2%, and 4.5%, respectively. Significant correlations with sRPE for individual fencers (r = .84–.98) and across mode of exercise (r = .73–.85) and competition stages (r = .82–.92) were found with HR-based measures. sRPE is a simple and valuable tool coaches can use to quantify TL in fencing.

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Jason C. Bartram, Dominic Thewlis, David T. Martin and Kevin I. Norton

Purpose:

New applications of the critical-power concept, such as the modeling of intermittent-work capabilities, are exciting prospects for elite cycling. However, accurate calculation of the required parameters is traditionally time invasive and somewhat impractical. An alternative single-test protocol (3-min all-out) has recently been proposed, but validation in an elite population is lacking. The traditional approach for parameter establishment, but with fewer tests, could also prove an acceptable compromise.

Methods:

Six senior Australian endurance track-cycling representatives completed 6 efforts to exhaustion on 2 separate days over a 3-wk period. These included 1-, 4-, 6-, 8-, and 10-min self-paced efforts, plus the 3-min all-out protocol. Traditional work-vs-time calculations of CP and anaerobic energy contribution (W′) using the 5 self-paced efforts were compared with calculations from the 3-min all-out protocol. The impact of using just 2 or 3 self-paced efforts for traditional CP and W′ estimation was also explored using thresholds of agreement (8 W, 2.0 kJ, respectively).

Results:

CP estimated from the 3-min all-out approach was significantly higher than from the traditional approach (402 ± 33, 351 ± 27 W, P < .001), while W′ was lower (15.5 ± 3.0, 24.3 ± 4.0 kJ, P = .02). Five different combinations of 2 or 3 self-paced efforts led to CP estimates within the threshold of agreement, with only 1 combination deemed accurate for W′.

Conclusions:

In elite cyclists the 3-min all-out approach is not suitable to estimate CP when compared with the traditional method. However, reducing the number of tests used in the traditional method lessens testing burden while maintaining appropriate parameter accuracy.

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Brett S. Nickerson, Michael R. Esco, Phillip A. Bishop, Brian M. Kliszczewicz, Kyung-Shin Park and Henry N. Williford

The purpose of this study was twofold: 1) compare body volume (BV) estimated from dual energy X-ray absorptiometry (DXA) to BV from a criterion underwater weighing (UWW) with simultaneous residual lung volume (RLV), and 2) compare four-compartment (4C) model body fat percentage (BF%) values when deriving BV via DXA (4CDXA) and UWW (4CUWW) in physically active men and women. One hundred twenty-two adults (62 men and 60 women) who self-reported physical activity levels of at least 1,000 MET·min·wk-1 volunteered to participate (age = 22 ± 5 years). DXA BV was determined with the recent equation from Smith-Ryan et al. while criterion BV was determined from UWW with simultaneous RLV. The mean BV values for DXA were not significant compared with UWW in women (p = .80; constant error [CE] = 0.0L), but were significantly higher in the entire sample and men (both p < .05; CE = 0.3 and 0.7L, respectively). The mean BF% values for 4CDXA were not significant for women (p = .56; CE = –0.3%), but were significantly higher in the entire sample and men (both p < .05; CE = 0.9 and 2.0%, respectively). The standard error of estimate (SEE) ranged from 0.6–1.2L and 3.9–4.2% for BV and BF%, respectively, while the 95% limits of agreement (LOA) ranged from ±1.8–2.5L for BV and ±7.9–8.2% for BF%. 4CDXA can be used for determining group mean BF% in physically active men and women. However, due to the SEEs and 95% LOAs, the current study recommends using UWW with simultaneous RLV for BV in a criterion 4C model when high individual accuracy is desired.

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Suzanne Houwen, Esther Hartman, Laura Jonker and Chris Visscher

This study examines the psychometric properties of the Test of Gross Motor Development-2 (TGMD-2) in children with visual impairments (VI). Seventy-five children aged between 6 and 12 years with VI completed the TGMD-2 and the Movement Assessment Battery for Children (Movement ABC). The internal consistency of the TGMD-2 was found to be high (alpha = 0.71−0.72) and the interrater, intrarater, and test-retest reliability acceptable (ICCs ranging from 0.82 to 0.95). The results of the factor analysis supported internal test structure and significant age and sex effects were observed. Finally, the scores on the object control subtest of the TGMD-2 and the ball skills subtest of the Movement ABC correlated moderately to high (r = 0.45 to r = 0.80). Based on the current results, it is concluded that the TGMD-2 is an appropriate tool to assess the gross motor skills of primary-school-age children with VI.