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Marcus V.V. Lopes, Bruno G.G. da Costa, Luis E.A. Malheiros, Rafael M. Costa, Ana C.C. Souza, Inacio Crochemore-Silva, and Kelly S. Silva

This study (a) compared accelerometer wear time and compliance between distinct wrist-worn accelerometer data collection plans, (b) analyzed participants’ perception of using accelerometers, and (c) identified sociodemographic and behavioral correlates of accelerometer compliance. A sample of high school students (n = 143) wore accelerometers attached to the wrist by a disposable polyvinyl chloride (PVC) wristband or a reusable fabric wristband for 24 hr over 6 days. Those who wore the reusable fabric band, but not their peers, were instructed to remove the device during water-based activities. Participants answered a questionnaire about sociodemographic and behavioral characteristics and reported their experience wearing the accelerometer. We computed non-wear time and checked participants’ compliance with wear-time criteria (i.e., at least three valid weekdays and one valid weekend day) considering two valid day definitions separately (i.e., at least 16 and 23 hours of accelerometer data). Participants who wore a disposable band had greater compliance compared with those who wore a reusable band for both 16-hr (93% vs. 76%, respectively) and 23-hr valid day definitions (91% vs. 50%, respectively). High schoolers with the following characteristics were less likely to comply with wear time criteria if they (a) engaged in labor-intensive activities, (b) perceived that wearing the monitor hindered their daily activities, or (c) felt ashamed while wearing the accelerometer. In conclusion, the data collection plan composed of using disposable wristbands and not removing the monitor resulted in greater 24-hr accelerometer wear time and compliance. However, a negative experience in using the accelerometer may be a barrier to high schoolers’ adherence to rigorous protocols.

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Gislaine S. Kogure, Cristiana L. Miranda-Furtado, Daiana C.C. Pedroso, Victor B. Ribeiro, Matheus C. Eiras, Rafael C. Silva, Lisandra C. Caetano, Rui A. Ferriani, Rodrigo T. Calado, and Rosana M. dos Reis

Background: Physical activity is prescribed as a component of primary management for polycystic ovary syndrome (PCOS). This nonrandomized, therapeutic, open, single-arm study investigated the effects of progressive resistance training (PRT) on obesity indices in women with PCOS, and the relationship between obesity indices and telomere content. Methods: A total of 45 women with PCOS and 52 with non-PCOS (controls), aged 18 to 37 years, with body mass indexes of 18 to 39.9 kg/m2, performed three 1-hour sessions of PRT per week, for 16 weeks. Before and after PRT, measures included anthropometric indices and regions of interest of fat mass distribution, quantified by dual-energy X-ray absorptiometry, metabolic and hormonal parameters, and telomere content. The general linear mixed models were used to determine the effects of PRT. Results: PRT did reduce the waist-to-height ratio, waist circumference, and the index of conicity among PCOS (P < .01). However, PRT did not influence regions of interest, body mass index, and WHR. After PRT, the telomere content was associated with regions of interest and anthropometric indices in whole group independent of PCOS (P < .05). Conclusion: Resistance exercise improves obesity indices in PCOS, independent of changes in body weight, and the relationship between telomeres and obesity parameters in PCOS remain to be fully clarified.

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Bruno G.G. da Costa, Kelly S. da Silva, Rafael M. da Costa, Edio L. Petroski, Isabela C. Back, Paulo H.A. Guerra, and Luiz R.A. de Lima

Purpose: Sedentary behavior (SB) has been shown to be associated with unhealthy outcomes in children, and it is not clear whether children living with human immunodeficiency virus (HIV) engage in different patterns of SB compared with healthy children. This cross-sectional study aimed to compare patterns of SB between children living with HIV and a healthy control group. Methods: A group of children with HIV and a paired control group wore accelerometers for 1 week and answered a questionnaire with items related to television viewing habits and computer usage. Accelerometer-derived and self-reported SB were compared between children living with HIV and controls and between treatment-based and viral load subgroups. Results: A total of 130 children (of which 53% are girls with a mean age of 12.1 y) participated in the study with 65 in each group. Children in the control group exhibited significantly more objectively measured SB daily when compared with the HIV group (515 vs 490 min/d, respectively), but no differences were found between the treatment-based and viral load subgroups. Children with HIV watched more television on weekdays, compared with the control group (P < .05). No other differences were found in comparisons of self-reported SB between the control and HIV and the treatment-based or viral load subgroups. Conclusion: Children living with HIV spend less time being sedentary than those in the healthy control group. Future studies are important for clarifying the causes and consequences of these differences.