Effects of activity tracker-based counselling and live-web exercise on breast cancer survivors' sleep and waking time during Italy's COVID-19 lockdown.

The aim of the study was to compare the effects of weekly personal feedback, based on objectively measured physical activity, on daily sleep in breast cancer survivors (BCS) with those of an intervention that also included online supervised physical exercise sessions (OSPES). BCS benefiting from both personal feedback and OSPES (n = 24), from pre-lockdown (T0) to the first month (T1) of the national lockdown, experienced an increase in both total (p ≤ 0.001) and restorative (p ≤ 0.001) sleep time, inverting their trend from the first month of lockdown to its end (total sleeping time T1 vs. T2 0.01 ≤ p < .001, T1 vs. T3 p ≤ 0.001; restorative sleeping time T1 vs. T2 0.05 ≤ p < .01, T1 vs. T3 p ≤ 0.001). Supportive technology, together with the reception of weekly tailored advice and OSPES seems to improve both quality and quantity of sleep.

Identifying waking time in 24-h accelerometry data in adults using an automated algorithm.

As accelerometers are commonly used for 24-h measurements of daily activity, methods for separating waking from sleeping time are necessary for correct estimations of total daily activity levels accumulated during the waking period. Therefore, an algorithm to determine wake and bed times in 24-h accelerometry data was developed and the agreement of this algorithm with self-report was examined. One hundred seventy-seven participants (aged 40-75 years) of The Maastricht Study who completed a diary and who wore the activPAL3™ 24 h/day, on average 6 consecutive days were included. Intraclass correlation coefficient (ICC) was calculated and the Bland-Altman method was used to examine associations between the self-reported and algorithm-calculated waking hours. Mean self-reported waking hours was 15.8 h/day, which was significantly correlated with the algorithm-calculated waking hours (15.8 h/day, ICC = 0.79, P = < 0.001). The Bland-Altman plot indicated good agreement in waking hours as the mean difference was 0.02 h (95% limits of agreement (LoA) = -1.1 to 1.2 h). The median of the absolute difference was 15.6 min (Q1-Q3 = 7.6-33.2 min), and 71% of absolute differences was less than 30 min. The newly developed automated algorithm to determine wake and bed times was highly associated with self-reported times, and can therefore be used to identify waking time in 24-h accelerometry data in large-scale epidemiological studies.

Weekdays' sleeping condition and its influence on occurrence of general malaise in Japanese children aged 10 to 12 years.

The present study aimed to elucidate weekdays' sleeping condition and its influence on occurrence of general malaise in children. A total of 761 Japanese children aged 10 to 12 years were surveyed regarding their weekdays' waking time and bedtime and general malaise using a self-administered questionnaire. As the result of hierarchical cluster analysis on the sleep condition, the participants were classified into three clusters. Sleep duration was significantly longer in cluster 1 (9.35 ± 0.52 h) than in clusters 2 (7.83 ± 0.77 h) and 3 (9.02 ± 0.30 h) and significantly longer in cluster 3 than in cluster 2. Waking time was significantly later in cluster 3 (7:01 ± 0:12) than in clusters 1 (6:22 ± 0:31) and 2 (6:24 ± 0:33, p < 0.001). Bedtime was significantly later in cluster 2 (22:34 ± 0:47) than in clusters 3 (21:59 ± 0:19) and 1 (21:01 ± 0:22) and significantly later in cluster 3 than in cluster 1. There were significantly more subjects in cluster 2 than in clusters 1 and 3 who responded "nearly every day" or "occasionally" to the five of seven questionnaires related to general malaise. The current results indicate that in Japanese children aged 10 to 12 years, (1) sleeping condition of weekdays are classified into three clusters with different mean values for each of sleep duration, bedtime, and waking time, and (2) the occurrence of general malaise may be enhanced in individuals whose sleep duration is less than 8 h.