RESUMEN
BACKGROUND: Regular moderate-to-vigorous physical activity (MVPA) is inversely associated with cardiovascular diseases in older adults. However, it remains unclear how the use of different cutoff points affects the associations with cardiovascular markers. OBJECTIVE: To analyze the association between different cutoff points for objectively measured MVPA and cardiometabolic markers in older adults. METHODS: This was a cross-sectional study involving 425 older adults (aged ≥60 years) from the EpiFloripa Ageing cohort study. We used ActiGraph accelerometers to measure MVPA in total minutes and in bouts (≥10â¯min) for at least 4 days. The tested cardiometabolic markers were waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein cholesterol (HDL-c), body mass index (BMI), triglycerides, fasting glucose and glycated hemoglobin (HbA1c). To identify MVPA, we used the cutoff points of Freedson et al. (≥ 1952 counts/min), Copeland and Esliger (≥ 1040 counts/min), and Troiano et al (≥ 2020 counts/min). RESULTS: We observed significant differences in MVPA (total and bouts) between the different cutoff points (pâ¯<â¯.001). The magnitude and number of associations between cardiometabolic markers and MVPA varied according to measurement units (total minutes: WC, SBP, DBP, HDL-c, BMI, triglycerides, glucose, and HbA1c versus bouts: WC, DBP, SBP HDL-c, and BMI) and cutoff points (higher associations for the Copeland and Esliger cutoff in total minutes and for the Troiano et al. cutoff in bouts of ≥10â¯min). CONCLUSION: The use of different cutoff points in evaluating accelerometer-measured MVPA in older adults provides conflicting estimates, which emphasizes the importance of standardized thresholds.
RESUMEN
BACKGROUND: To examine the level of physical activity and sedentary behavior (SB), measured with accelerometers, in older adults from a city in southern Brazil according to sociodemographic and health characteristics. METHODS: The sample consisted of 425 older adults (≥63 y) from the EpiFloripa Aging Study. Light physical activity (LPA), moderate to vigorous physical activity (MVPA), and SB were measured with accelerometers over a period of 7 days. RESULTS: The older adults spent two-thirds of the time of use in SB, one-third in LPA, and only 2.1% (95% confidence interval, 1.8-2.2) in MVPA. In the final adjusted model, lower levels of MVPA were observed for women, as well as higher SB and lower LPA and MVPA for those with higher age. There were also trends toward prolonged SB and lower LPA when participants had a higher educational level and toward lower MVPA with higher body mass index. CONCLUSIONS: Constant monitoring of physical activity levels and SB using objective measures is recommended and interventions should be directed at the groups most exposed to excessive SB and low levels of MVPA.
Asunto(s)
Acelerometría/métodos , Ejercicio Físico/fisiología , Conducta Sedentaria , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Brasil , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
O objetivo do presente estudo foi apresentar um conjunto de orientações para a utilização de acelerômetros no Brasil. O método consistiu na revisão e síntese de artigos que utilizaram acelerômetros como instrumento de medida objetiva da atividade física. Com base nesses estudos, buscou-se apresentar orientações para as fases pré-coleta (seleção do acelerômetro; testagem da calibração dos acelerômetros, atualização de firmware; estudo piloto; e definição de protocolo), coleta (distribuição dos acelerômetros; contato com participantes; e devolução dos acelerômetros) e pós-coleta (processamento; transformação e interpretação dos dados; e comparabilidade dos dados) do uso de acelerômetros. São descritos procedimentos para facilitar as tomadas de decisões relacionadas ao uso desses dispositivos, bem como para obtenção de dados de acelerometria válidos e reprodutíveis. As orientações são uma iniciativa de pesquisadores da área a fim de proporcionar um avanço metodológico nas medidas objetivas da atividade física. A adoção das orientações pode facilitar a padronização dos procedimentos empregados e a comparabilidade de resultados entre estudos com acelerômetros no Brasil.
The aim of this study was to develop instructions for using accelerometers to measure physical activity in Brazil. This manuscript is a review and synthesis of scientific papers that have used accelerometers for objective physical activity assessment in different age groups as well as studies providing directions for using activity monitors in large-scale studies. In this study, we present instructions for the pre-data collection (selection of monitor; unit calibration, firmware update, pilot study, protocol definition), data collection (monitor distribution, contacting participants, monitor return) and post-data collection (data processing, transformation and interpretation) phases. We describe procedures for facilitating decision making related to using accelerometers, as well as for obtaining valid and reliable accelerometer physical activity data. This set of instructions is an initiative of a group of physical activity researchers with the purpose of contributing to methodologically advance the field of objective physical activity measurement in Brazil. The current set of instructions intend to facilitate the standardization of procedures for collecting physical activity data with accelerometers in Brazil and, thus, for ascertaining future comparability of data collected in different studies.
