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Tim J. Gabbett and Boris Georgieff

Purpose:

To develop a skill assessment for junior volleyball players and to evaluate the reliability, validity, and sensitivity of the test for detecting training-induced improvements in skill.

Methods:

Thirty junior volleyball players (mean ± SD age, 15.5 ± 1.0 years) participated in this study. Subjects performed tests of spiking, setting, serving, and passing skills on 2 separate occasions to determine test–retest reliability of accuracy. Two expert coaches evaluated the players’ technique and reevaluated it 1 month after the initial evaluation to determine the intratester reliability for technique measurements. A third expert coach determined the intertester reliability for technique measurements. The validity of the test to discriminate players of different playing abilities was evaluated by testing junior national, state, and novice volleyball players. Finally, each player participated in an 8-week skill-based training program.

Results:

Accuracy measurements and intratester and intertester ratings of players’ technique proved to be highly reproducible (intraclass correlation coefficient, r, .85 to .98, range of typical error of measurement 0.2% to 10.0%). A progressive improvement in skill was observed with increases in playing level, while training-induced improvements were present in all skill tasks.

Conclusions:

These results demonstrate that skill-based testing offers a reliable method of quantifying development and progress in junior volleyball players. In addition, the skill-testing battery was useful in successfully discriminating playing ability among junior volleyball players of varying levels, and it was sensitive to changes in skill with training. These fi ndings demonstrate that skill-based testing is useful for monitoring the development of junior volleyball players.

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Patrick B. Wilson, Gregory S. Rhodes and Stacy J. Ingraham

Purpose:

Self-report (SR) has been the primary method used to assess fluid intake during endurance events, but unfortunately, little is known about the validity of SR. The purpose of this study was to compare SR fluid intake with direct measurement (DM) during a 70.3-mile triathlon.

Methods:

Fifty-three (42 men, 11 women) individuals competing in a 70.3-mile triathlon participated in the study. On the 13.1-mile-run section of the triathlon, 11 research stations provided fluid in bottles filled with 163 mL of water or carbohydrate-electrolyte beverage (CEB). Participants submitted bottles 25 m past aid stations to be reweighed postrace. Participants also answered questions regarding fluid intake postrace. Bland-Altman plots and 95% limits of agreement were used to assess precision of the measures, while least-squares regression assessed linear agreement.

Results:

SR intakes during the run ranged from 0–1793, 0–1837, and 0–2628 mL for water, CEB, and total fluid, with corresponding DM intakes of 0–1599, 0–1642, and 0–2250 mL. DM and SR showed strong linear agreement for water, CEB, and total fluid (R 2 = .71, .80, and .80). Mean differences between the measures on the Bland-Altman plots were small (13–41 mL), but relatively large differences (±500 mL) between the measures were apparent for some participants.

Conclusions:

SR is the predominant methodology used in field studies assessing hydration, despite little to no data confirming its validity. The results herein suggest that fluid-intake-assessment methodology should be chosen on a case-by-case basis and that caution should be used when interpreting data based on SR.

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Jeremy M. Sheppard, Tim Gabbett, Kristie-Lee Taylor, Jason Dorman, Alexis J. Lebedew and Russell Borgeaud

Purpose:

The authors conducted a study to develop a repeated-effort test for international men’s volleyball. The test involved jumping and movement activity that was specific to volleyball, using durations and rest periods that replicated the demands of a match.

Methods:

A time–motion analysis was performed on a national team and development national team during international matches to determine the demands of competition and thereby form the basis of the rationale in designing the repeated-effort test. An evaluation of the test for reliability and validity in discriminating between elite and sub-elite players was performed.

Results:

The test jump height and movement-speed test parameters were highly reliable, with findings of high intraclass correlations (ICCs) and low typical errors of measurement (TE; ICC .93 to .95 and %TE 0.54 to 2.44). The national team’s ideal and actual jump height and ideal and actual speeds, mean ± SD, were 336.88 ± 8.31 cm, 329.91 ± 6.70 cm, 6.83 ± 0.34 s, and 7.14 ± 0.34 s, respectively. The development national team’s ideal and actual jump heights and ideal and actual speeds were 330.88 ± 9.09 cm, 323.80 ± 7.74 cm, 7.41 ± 0.56 s, and 7.66 ± 0.56 s, respectively. Probabilities of differences between groups for ideal jump, actual jump, ideal time, and actual time were 82%, 95%, 92%, and 96%, respectively, with a Cohen effect-size statistic supporting large magnitudes (0.69, 0.84, 1.34, and 1.13, respectively).

Conclusion:

The results of this study demonstrate that the developed test offers a reliable and valid method of assessing repeated-effort ability in volleyball players.

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Iñigo Mujika, Greg McFadden, Mark Hubbard, Kylie Royal and Allan Hahn

Purpose:

To develop and validate an intermittent match-fitness test for water-polo players.

Methods:

Eight male junior players performed the Water Polo Intermittent Shuttle Test (WIST) twice to assess test reliability. To assess test sensitivity and validity, 104 male and female players from different competition standards and playing positions were tested. Eighteen players performed the WIST 5 times throughout a season to track fitness changes. Twelve players performed the WIST 48 hours before 4 consecutive National League games, and coaches awarded individual match-fitness scores based on game performances to assess the relationship between match fitness and test results. Heart rate (HR) and blood lactate (Lablood) were measured during and after each test, respectively.

Results:

Test–retest performance values were 216 ± 90 vs 229 ± 96 m (r = .98, P = .0001, coefficient of variation [CV] = 5.4%), peak HR 190 ± 8 vs 192 ± 10 bpm (r = .96, P = .0002, CV = 1.2%), and Lablood 7.0 ± 1.8 vs 6.4 ± 1.6 mmol/L (r = .84, P = .0092, CV = 8.8%). Significant differences were observed among different standards of play (range junior regional females 102 ± 10 m, senior international males 401 ± 30 m) and playing positions (field players 305 ± 154 m, center forwards 255 ± 118, goal keepers 203 ± 135 m). Test performance was lower in the early season (344 ± 118 m) than the remainder of the season (range 459 ± 138 to 550 ± 176 m). WIST performance and match-fitness scores correlated for all field players (r = .57, P = .054) but more highly for field players other than center forwards (r = .83, P = .0027).

Conclusions:

The WIST is a reliable, sensitive, and valid match-fitness test for water-polo players. It could become a useful tool to assess the effects of different interventions on match fitness.

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Toshimasa Yanai, Akifumi Matsuo, Akira Maeda, Hiroki Nakamoto, Mirai Mizutani, Hiroaki Kanehisa and Tetsuo Fukunaga

developed a force measurement system embedded under a soil-filled mound. 5 This system may be installed in a baseball field and used for monitoring pitching techniques in real-time during practice and game situations. It is, therefore, worthwhile to list reliable and valid biomechanical parameters

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Øystein Sylta, Espen Tønnessen and Stephen Seiler

Purpose:

The purpose of this study was to validate the accuracy of self-reported (SR) training duration and intensity distribution in elite endurance athletes.

Methods:

Twenty-four elite cross-country skiers (25 ± 4 y, 67.9 ± 9.88 kg, 75.9 ± 6.50 mL · min−1 · kg−1) SR all training sessions during an ~14-d altitude-training camp. Heart rate (HR) and some blood lactate measurements were collected during 466 training sessions. SR training was compared with recorded training duration from HR monitors, and SR intensity distribution was compared with expert analysis (EA) of all session data.

Results:

SR training was nearly perfectly correlated with recorded training duration (r = .99), but SR training was 1.7% lower than recorded training duration (P < .001). SR training duration was also nearly perfectly correlated (r = .95) with recorded training duration >55% HRmax, but SR training was 11.4% higher than recorded training duration >55% HRmax (P < .001) due to SR inclusion of time <55% HRmax. No significant differences were observed in intensity distribution in zones 1–2 between SR and EA comparisons, but small discrepancies were found in zones 3–4 (P < .001).

Conclusions:

This study provides evidence that elite endurance athletes report their training data accurately, although some small differences were observed due to lack of a SR “gold standard.” Daily SR training is a valid method of quantifying training duration and intensity distribution in elite endurance athletes. However, additional common reporting guidelines would further enhance accuracy.

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Tiago V. Barreira, Robert M. Brouillette, Heather C. Foil, Jeffrey N. Keller and Catrine Tudor-Locke

The purpose of this study was to compare the steps/d derived from the ActiGraph GT3X+ using the manufacturer’s default filter (DF) and low-frequency-extension filter (LFX) with those from the NL-1000 pedometer in an older adult sample. Fifteen older adults (61–82 yr) wore a GT3X+ (24 hr/day) and an NL-1000 (waking hours) for 7 d. Day was the unit of analysis (n = 86 valid days) comparing (a) GT3X+ DF and NL-1000 steps/d and (b) GT3X+ LFX and NL-1000 steps/d. DF was highly correlated with NL-1000 (r = .80), but there was a significant mean difference (–769 steps/d). LFX and NL-1000 were highly correlated (r = .90), but there also was a significant mean difference (8,140 steps/d). Percent difference and absolute percent difference between DF and NL-1000 were –7.4% and 16.0%, respectively, and for LFX and NL-1000 both were 121.9%. Regardless of filter used, GT3X+ did not provide comparable pedometer estimates of steps/d in this older adult sample.

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Katie Weatherson, Lira Yun, Kelly Wunderlich, Eli Puterman and Guy Faulkner

occupational sitting time within office environments. 5 Interventions aimed at reducing sitting or increasing PA, depend on valid and reliable measures of these behaviours. 6 Retrospective self-report methods of assessing these behaviors rely on participants to recall past experience (within some defined

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Paul M. Vanderburgh

Purpose:

To assess the validity of Boston Marathon qualifying (BMQ) standards for men and women.

Methods:

Percent differences between BMQ and current world records (WR) by sex and age group were computed. WR was chosen as the criterion comparison because it is not confounded by intensity, body composition, lifestyle, or environmental factors. A consistent difference across age groups would indicate an appropriate slope of the age-vs-BMQ curve. Inconsistent differences were corrected by adjusting BMQ standards to achieve a uniform percentage difference from WR.

Results:

BMQ standards for men were consistently ~50% slower than WR (mean 51.5% ± 1.4%, range 49.6–54.4%), thus demonstrating acceptable validity. However, BMQ standards for women indicated convergence with WR as age increased (mean 45.8% ± 13.7%, range 17.5–58.9%). The women’s BMQ standards were revised to yield a consistent 50% deviation from WR across age groups (50.9% ± 0.8%, range 49.2–52.2%). Applied to all 16,773 women in the 2012 Chicago Marathon, the suggested BMQ standards would lead to a 4.90% success rate, compared with 8.39% using the current standard. This compared with a 9.6% success rate for all 20,681 men of the same race.

Conclusions:

The current women’s BMQ standards appear too lenient for women 18–54 y and too strict for women 55–80 y but yield equitable gender representation in percentage of qualifiers. The current men’s and suggested women’s BMQ standards appear valid but would lead to approximately 40% fewer women achieving BMQ standards.

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James Wright, Thomas Walker, Scott Burnet and Simon A. Jobson

reliability and validity of the PowerTap P1 pedals have been investigated between 100 and 500 W at 70, 85, and 100 rpm. 7 These authors reported that the P1 pedals slightly underestimated the SRM Powermeter by 2 to 7 W but suggested that the pedals were reliable and valid, concluding that they were a cost