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Orjan Ekblom, Gisela Nyberg, Elin Ekblom Bak, Ulf Ekelund and Claude Marcus

Background:

Wrist-worn accelerometers may provide an alternative to hip-worn monitors for assessing physical activity as they are easier to wear and may thus facilitate long-term recordings. The current study aimed at a) assessing the validity of the Actiwatch (wrist-worn) for estimating energy expenditure, b) determining cut-off values for light, moderate, and vigorous activities, c) studying the comparability between the Actiwatch and the Actigraph (hip-worn), and d) assessing reliability.

Methods:

For validity, indirect calorimetry was used as criterion measure. ROC-analyses were applied to identify cut-off values. Comparability was tested by simultaneously wearing of the 2 accelerometers during free-living condition. Reliability was tested in a mechanical shaker.

Results:

All-over correlation between accelerometer output and energy expenditure were found to be 0.80 (P < .001).Based on ROC-analysis, cut-off values for 1.5, 3, and 6 METs were found to be 80, 262, and 406 counts per 15 s, respectively. Energy expenditure estimates differed between the Actiwatch and the Actigraph (P < .05). The intra- and interinstrument coefficient of variation of the Actiwatch ranged between 0.72% and 8.4%.

Conclusion:

The wrist-worn Actiwatch appears to be valid and reliable for estimating energy expenditure and physical activity intensity in children aged 8 to 10 years.

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Lanae M. Joubert and Melinda M. Manore

Homocysteine is an independent cardiovascular disease (CVD) risk factor modi-fable by nutrition and possibly exercise. While individuals participating in regular physical activity can modify CVD risk factors, such as total blood cholesterol levels, the impact physical activity has on blood homocysteine concentrations is unclear. This review examines the influence of nutrition and exercise on blood homocysteine levels, the mechanisms of how physical activity may alter homocys-teine levels, the role of homocysteine in CVD, evidence to support homocysteine as an independent risk factor for CVD, mechanisms of how homocysteine increases CVD risk, and cut-off values for homocysteinemia. Research examining the impact of physical activity on blood homocysteine levels is equivocal, which is partially due to a lack of control for confounding variables that impact homocysteine. Duration, intensity, and mode of exercise appear to impact blood homocysteine levels differently, and may be dependent on individual fitness levels.

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Addie Middleton, Stacy L. Fritz and Michelle Lusardi

Walking speed (WS) is a valid, reliable, and sensitive measure appropriate for assessing and monitoring functional status and overall health in a wide range of populations. These capabilities have led to its designation as the “sixth vital sign”. By synthesizing the available evidence on WS, this scholarly review article provides clinicians with a reference tool regarding this robust measure. Recommendations on testing procedures for assessing WS, including optimal distance, inclusion of acceleration and deceleration phases, instructions, and instrumentation are given. After assessing an individual’s WS, clinicians need to know what this value represents. Therefore, WS cut-off values and the corresponding predicted outcomes, as well as minimal detectable change values for specific populations and settings are provided.

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Robert A. Oppliger, Scott A. Magnes, LeRoy A. Popowski and Carl V. Gisolfi

To reduce the adverse consequences of exertion-related and acute intentional dehydration research has focused on monitoring hydration status. This investigation: 1) compared sensitivity of urine specific gravity (Usg), urine osmolality (Uosm) and a criterion measurement of hydration, plasma osmolality (Posm), at progressive stages of acute hypertonic dehydration and 2) using a medical decision model, determined whether Usg or Uosm accurately reflected hydra-tion status compared to Posm among 51 subjects tested throughout the day. Incremental changes in Posm were observed as subjects dehydrated by 5% of body weight and rehydrated while Usg and Uosm showed delayed dehydration-related changes. Using the medical decision model, sensitivity and specificity were not significant at selected cut-offs for Usg and Uosm. At the most accurate cut-off values, 1.015 and 1.020 for Usg and 700 mosm/kg and 800 mosm/kg for Uosm, only 65% of the athletes were correctly classified using Usg and 63% using Uosm. Posm, Usg, and Uosm appear sensitive to incremental changes in acute hypertonic dehydration, however, the misclassified outcomes for Usg and Uosm raise concerns. Research focused on elucidating the factors affecting accurate assessment of hydration status appears warranted.

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Gustavo Silva, Luísa Aires, Jorge Mota, José Oliveira and José Carlos Ribeiro

The purpose of this study was to calculate and validate reference standards for the 20-m shuttle run test (SR) in youths aged 10–18 years. Reference standards based on the number of completed SR laps were calculated by LMS method in a reference group of 5559 students. Cut-off values for SR laps were determined and tested by ROC curve analysis in a validation group (633 students), from which waist circumference, HDL-cholesterol, triglycerides, fasting glucose and mean arterial pressure were assessed to calculate a metabolic risk score, later dichotomized in low and high metabolic risk (HMRS). The accuracy of SR laps standards was significant for girls (AUC = 0.66; 95% CI = 0.58–0.74; p < .001) and boys (AUC = 0.71; 95% CI = 0.62–0.79; p < .001) for identifying subjects at HMRS. The 40th percentile was the best cut-off for SR laps in girls (SENS = 0.569; 1-SPEC = 0.330) and boys (SENS = 0.634; 1-SPEC = 0.266). New SR laps reference standards are able to discriminate metabolic risk levels, and may provide a valuable tool for early prevention of cardiovascular risk factors.

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Jodie E. Southall, Anthony D. Okely and Julie R. Steele

This study compared actual and perceived physical competence of overweight and nonoverweight children. Participants were 109 nonoverweight and 33 overweight Grade 5 and 6 children (mean age 10.8 years). Overweight status was determined using age- and gender-specific international body-mass-index cut-off values. Actual competence was assessed using the Test of Gross Motor Development, 2nd ed., and perceived competence was assessed using an expanded version of the Athletic Competence subscale of the Self-Perception Profile for Children (SPPC). Overweight children had significantly lower actual and perceived physical competence. When actual competence was partitioned into locomotor and object-control skills, however, differences only existed for locomotor skills. These findings indicate that low actual and perceived physical competence might be important contributing factors in maintaining childhood obesity. Interventions to improve actual and perceived physical competence in overweight children should provide opportunities to learn and master fundamental movement skills in an environment where parents, teachers, and coaches provide positive and specific feedback, encouragement, and modeling.

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Jennifer Brunet, Eva Guérin and Nicolas Speranzini

are no definite guidelines for what cut-off values constitute an adequate fit to the data, models with a nonsignificant MLRχ 2 , CFI and TLI values ≥ .95, RMSEA values ≤ .08, and SRMR values ≤ .10 are considered to indicate acceptable fit based on rules of thumb for model evaluation ( Hu & Bentler

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Megan Colletto and Nancy Rodriguez

suggested as a cut off value in the prediction of metabolic syndrome in postmenopausal women ( Gadelha et al., 2016 ). Body fat for CON was 39% compared to 32% for YOGA, implying that routine yoga practice may be an alternative mode of exercise for preventing the typical increase in body fat observed with

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Silvia Gonçalves Ricci Neri, André Bonadias Gadelha, Ana Luiza Matias Correia, Juscélia Cristina Pereira, Ana Cristina de David and Ricardo M. Lima

Paulo, Brazil), and height was measured at the nearest 0.1 cm with a wall stadiometer (WCS/CARDIOMED, Curitiba, Brazil). BMI was derived as body mass divided by height squared (kg/m 2 ). The cut-off value for obesity and overweight was 30 kg/m 2 and 25 kg/m 2 , respectively. Body fat distribution was

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Thilo Hotfiel, Marion Kellermann, Bernd Swoboda, Dane Wildner, Tobias Golditz, Casper Grim, Martin Raithel, Michael Uder and Rafael Heiss

tissue and its impact on the ARFIs has not been described. This could be an attempt for future research. However, the subcutaneous fat tissue did not show any significant alterations between baseline and DOMS in this study. Providing cut-off values to decide when ARFI SWVs begin to normalize may help to