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Benjamin W. Infantolino, Daniel J. Gales, Samantha L. Winter and John H. Challis

The purpose of this study was to validate ultrasound muscle volume estimation in vivo. To examine validity, vastus lateralis ultrasound images were collected from cadavers before muscle dissection; after dissection, the volumes were determined by hydrostatic weighing. Seven thighs from cadaver specimens were scanned using a 7.5-MHz ultrasound probe (SSD-1000, Aloka, Japan). The perimeter of the vastus lateralis was identified in the ultrasound images and manually digitized. Volumes were then estimated using the Cavalieri principle, by measuring the image areas of sets of parallel two-dimensional slices through the muscles. The muscles were then dissected from the cadavers, and muscle volume was determined via hydrostatic weighing. There was no statistically significant difference between the ultrasound estimation of muscle volume and that estimated using hydrostatic weighing (p > 0.05). The mean percentage error between the two volume estimates was 0.4% ± 6.9. Three operators all performed four digitizations of all images from one randomly selected muscle; there was no statistical difference between operators or trials and the intraclass correlation was high (>0.8). The results of this study indicate that ultrasound is an accurate method for estimating muscle volumes in vivo.

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Stacy A. Clemes, Beverley M. David, Yi Zhao, Xu Han and Wendy Brown

Background:

In light of evidence linking sedentary behaviors to health outcomes, there have been calls for the measurement of sedentary behavior in surveillance studies. This study examined the convergent validity of 2 self-report measures of sitting time and accelerometer-determined sedentary time (minutes/day of <100 counts/minute).

Methods:

44 adults wore an ActiGraph accelerometer for 7 days, during which they also recorded daily sitting time in a diary, in response to a single-item question. After 7 days, participants completed a new domain-specific questionnaire to assess usual weekday and weekend-day sitting time. Total sitting times recorded from the self-report measures were compared with accelerometer-determined sedentary time.

Results:

Total sitting time calculated from the domain-specific questionnaire did not differ significantly from accelerometer-determined sedentary time on weekdays (mean difference [±SE] = –14 ± 28 mins/day) and weekend days (–4 ± 45 mins/day, both P > .05). Sitting time was significantly underestimated using the single-item specific-day question on weekdays (–173 ± 18 mins/day) and weekend days (–219 ± 23 mins/day, both P < .001).

Conclusions:

When assessed via self-report, the estimation of total sitting time is improved by summing sitting times reported across different domains. The continued improvement of self-report measures of sitting time will be important if we are to further our understanding of the links between sedentary behavior and health.

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Moataz Eltoukhy, Christopher Kuenze, Jeonghoon Oh, Eryn Apanovitch, Lauren Butler and Joseph F. Signorile

motion capture volume, can be utilized as a cost-effective 3DMA tool. 25 Previous studies reported the validity of the Kinect v2 in multiple applications including treadmill gait, 26 over-ground gait, 27 squatting, 28 and balance. 29 To the best of our knowledge, no prior study has examined the

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Kathryn Mills, Aula Idris, Thu-An Pham, John Porte, Mark Wiggins and Manolya Kavakli

first be established. The objectives of this study were (1) to evaluate the validity of a VR game in evaluating the projected frontal plane knee angle when landing from a jump and (2) to assess the reliability of this evaluation over time. Methods A cross-sectional laboratory study was used to determine

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Nicola Furlan, Mark Waldron, Mark Osborne and Adrian J. Gray

Purpose:

To assess the ecological validity of the Rugby Sevens Simulation Protocol (R7SP) and to evaluate its interday reliability.

Methods:

Ten male participants (20 ± 2 y, 74 ± 11 kg) completed 2 trials of the R7SP, separated by 7 d. The R7SP comprised typical running and collision activities, based on data recorded during international rugby sevens match play. Heart rate (HR) was monitored continuously during the R7SP, and the participants’ movements were recorded through a 20-Hz global positioning system unit. Blood lactate and rating of perceived exertion were collected before and immediately after the 1st and 2nd halves of the R7SP.

Results:

The average activity profile was 117 ± 5 m/min, of which 27 ± 2 m/min was covered at high speed, with a calculated energetic demand of 1037 ± 581 J/kg, of which ~40% was expended at a rate above 19 W/kg. Mean HR was 88% ± 4% of maximal HR. Participants spent ~45% ± 27% of time above 90% of maximal HR (t >90%HRmax). There were no significant differences between trials, except for lactate between the halves of the R7SP. The majority of the measured variables demonstrated a between-trials coefficient of variation (CV%) lower than 5%. Blood lactate measurements (14–20% CV) and t >90%HRmax (26% CV) were less reliable variables. In most cases, the calculated moderate worthwhile change was higher than the CV%.

Conclusions:

The R7SP replicates the activity profile and HR responses of rugby sevens match play. It is a reliable simulation protocol that can be used in a research environment to detect systematic worthwhile changes in selected performance variables.

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Andrew C. Sparkes

Evaluating the quality of qualitative inquiry has begun to intrigue researchers in sport psychology. Consequently, this has raised important questions regarding the criteria for judging this emerging form of inquiry. With the intent to stimulate methodological debate, this paper explores prevailing notions of validity in qualitative sport psychology by focusing on how various scholars have framed this term. The prevailing parallel perspective of validity is discussed, as are specific problems associated with this view. In contrast, recent attempts to reconceptualize validity in relation to particular forms of qualitative inquiry are considered. The socially constructed nature of validity and the multiplicity of meanings associated with this term are presented according to a diversification perspective. More radical calls to renounce validity and seek alternative criteria for judging qualitative inquiry are also discussed. In closing, the ongoing problem of criteria and its implications for research in sport psychology are considered.

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Herbert W. Marsh

The Physical Self-Description Questionnaire (PSDQ) is a multidimensional physical self-concept instrument with 11 scales: Strength, Body Fat, Activity, Endurance/Fitness, Sports Competence, Coordination, Health, Appearance, Flexibility, Global Physical, and Global Esteem. The purpose of this study is to evaluate the construct validity of PSDQ responses in relation to 23 external criteria, including measures of body composition, physical activity, endurance, strength, and flexibility for 192 (113 boys and 79 girls) high school students. Each external validity criterion was predicted a priori to be most highly correlated with one of the PSDQ scales. In support of the convergent validity of the PSDQ responses, every predicted correlation was statistically significant. In support of the discriminant validity of the PSDQ responses, most predicted correlations were larger than other correlations involving the same criterion. These results support the construct validity of PSDQ responses in relation to external criteria and their potential usefulness in a wide variety of sports and exercise settings.

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Jeremy A. Steeves, Brian M. Tyo, Christopher P. Connolly, Douglas A. Gregory, Nyle A. Stark and David R. Bassett

Background:

This study compared the validity of a new Omron HJ-303 piezoelectric pedometer and 2 other pedometers (Sportline Traq and Yamax SW200).

Methods:

To examine the effect of speed, 60 subjects walked on a treadmill at 2, 3, and 4 mph. Twenty subjects also ran at 6, 7, and 8 mph. To test lifestyle activities, 60 subjects performed front-back-side-side stepping, elliptical machine and stair climbing/descending. Twenty others performed ballroom dancing. Sixty participants completed 5 100-step trials while wearing 5 different sets of the devices tested device reliability. Actual steps were determined using a hand tally counter.

Results:

Significant differences existed among pedometers (P < .05). For walking, the Omron pedometers were the most valid. The Sportline overestimated and the Yamax underestimated steps (P < .05). Worn on the waist or in the backpack, the Omron device and Sportline were valid for running. The Omron was valid for 3 activities (elliptical machine, ascending and descending stairs). The Sportline overestimated all of these activities, and Yamax was only valid for descending stairs. The Omron and Yamax were both valid and reliable in the 100-step trials.

Conclusions:

The Omron HJ-303, worn on the waist, appeared to be the most valid of the 3 pedometers.

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Chris Lonsdale, Ken Hodge and Elaine A. Rose

The purpose of the four studies described in this article was to develop and test a new measure of competitive sport participants’ intrinsic motivation, extrinsic motivation, and amotivation (self-determination theory; Deci & Ryan, 1985). The items for the new measure, named the Behavioral Regulation in Sport Questionnaire (BRSQ), were constructed using interviews, expert review, and pilot testing. Analyses supported the internal consistency, test–retest reliability, and factorial validity of the BRSQ scores. Nomological validity evidence was also supportive, as BRSQ subscale scores were correlated in the expected pattern with scores derived from measures of motivational consequences. When directly compared with scores derived from the Sport Motivation Scale (SMS; Pelletier, Fortier, Vallerand, Tuson, & Blais, 1995) and a revised version of that questionnaire (SMS-6; Mallett, Kawabata, Newcombe, Otero-Forero, & Jackson, 2007), BRSQ scores demonstrated equal or superior reliability and factorial validity as well as better nomological validity.

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James Dollman, Rebecca Stanley and Andrew Wilson

Valid measurement of youth physical activity is important and self-report methods provide convenient assessments at the population level. There is evidence that the validity of physical activity self-report varies by weight category. The aim of this study was to assess the validity of the 3-Day Physical Activity Recall (3DPAR), separately between normal weight and overweight/obese Australian youth. Accelerometer-derived physical activity variables were compared with 3DPAR variables in 155 (77 females) 11- to 14-year-olds from Adelaide, South Australia. In the whole sample, validity coefficients for self-reported moderate and moderate to vigorous physical activity were modest (rs = 0.12-0.31) and similar across gender and weight status categories. Validity coefficients for self-reported vigorous physical activity were much stronger (rs = 0.59-0.73) among overweight/obese than among normal weight participants. The validity of the 3DPAR in this study was low in the whole sample but varied according to physical activity intensity and the weight status of the child. Specifically, the 3DPAR may be appropriate for describing vigorous intensity physical activity among overweight and obese youth.