Josh Fitton

Background The extent to which people routinely co-attain recommended sleep and physical activity levels, as well as bidirectional associations between both health behaviours, are poorly understood at the global level. This study aimed to describe the routine co-attainment of adequate sleep and daily step count thresholds and investigate non-linear associations between objective sleep and daily step count in a large multi-national sample of objective health monitoring data. Methods Data were collected from 70,963 users of two consumer-available health devices—an under-mattress sleep sensor and wrist-worn health tracker—between January 2020 and September 2023. Generalised additive models were used to investigate potentially non-linear, bidirectional, exposure-response relationships between sleep parameters (sleep duration, sleep efficiency, and sleep onset latency) and step count at the next-day/night level. Subgroup analyses were undertaken to investigate age-related differences in all effects. Results We show that only 12.9% of people achieve the recommended sleep duration of 7-9hrs/night and >8,000 steps/day, with 16.5% having short sleep (<7hrs/night) and sedentary lives (<5,000 steps/day). Approximately 6hrs sleep equates to the greatest next-day step count (e.g., +339 steps vs 8 hrs/night), and sleep efficiency positively predicts next-day step count in a dose-dependent manner (25th vs 75th percentile: +282 steps/day). Sleep appears largely unaffected by previous-day step count. Effects are similar across age groups but decline in magnitude when adjusted for ‘awake duration’. Conclusions Our findings provide insight into the bidirectional relationship between sleep-activity globally and highlight the need to ensure sleep and activity health recommendations are mutually attainable.

Integrated alongside home-based passive sleep monitoring, high-frequency assessment of patient reported outcomes (PROs) could enhance both research and clinical care surrounding obstructive sleep apnea (OSA). However, traditional approaches to capturing OSA-related PROs are poorly suited for this purpose. Hence, we investigated the feasibility of a smartphone-based check-in approach to monitor daily PROs (e.g. mental, emotional, and physical) over a 6-month period in people referred for suspected OSA. We quantified and assessed change in the proportion of participants (n = 68; 54% female) who, on average, achieved an “adequate” self-report rate of ≥4 self-reports per week (out of a possible seven). Generalized additive models (GAMs) were used to investigate if OSA severity (apnea-hypopnea index; AHI) was associated with the probability of adequate initial uptake within the first two weeks, sustained engagement over time, and the probability of a self-report on any given day. Self-reports were made on 52.1% of all possible days, equating to (M ± SD) 3.6 ± 3.0 per week. Within the first week, 63.2% of participants achieved “adequate” self-report compliance; during weeks 4 and 12, these rates were 70.6% and 54.4% , respectively. Greater baseline AHI was associated with slower time-dependent decline in the probability of adequate self-report compliance in an exposure-response manner. Within-subjects, daily self-reports were more probable following nights of elevated AHI (absolute and mean-referenced). All GAM smooth terms: p < .00001. Findings demonstrate the feasibility of bi-daily PRO assessment via app-based check-ins for approximately 1 month in the context of clinical OSA and suggest that greater disease burden enhances sustained engagement with this monitoring approach. This paper is part of the Consumer Sleep Technology Collection. Statement of Significance This study investigates the feasibility of using a brief, app-based questionnaire to capture daily patient-reported outcomes in people with obstructive sleep apnea (OSA), over a 6-month period. Findings are promising, with a large proportion of people achieving more than four self-reports per week, on average, for approximately 1 month. Notably, higher OSA severity at baseline was associated with more sustained self-report engagement across the monitoring period. Furthermore, participants were more likely to make a self-report if their OSA severity was poorer than usual on the previous night. These results support the feasibility of app-based check-ins for the high-frequency monitoring of OSA’s daytime consequences as part of a home-based symptom monitoring approach.

This study explores the dynamics of sleep, somatic/psychological experience, and exercise performance before, during, and after the Tour de France (TDF). Objective and subjective sleep, self‐reported perceived experience, and objective exercise performance data were collected daily from eight elite male cyclists across a 6‐week period including the 3‐week TDF and 11‐day pre‐ and post‐race periods. Associations between, and temporal changes in, primary interest metrics were explored through Pearson correlation and linear mixed models. Participants were (mean ± SD) aged 30 ± 4 years with overall objective sleep duration of 8 h 11mins (±58 min) per night. Sleep quality (0–100) was lower during the race than pre‐race (β [95% CI]; −8.0[−11.7, −4.3]). During the pre‐race period, sleep onset (4 [2, 5] mins) and offset times delayed (5 [3, 7] mins) and self‐reported stress increased (1.87 [1.14, 2.61]) daily. Increases in muscular soreness (0.6 [0.3, 0.8]) and fatigue (0.4 [0.2, 0.6]) during the race preceded daily declines during the post‐race period (−3.1 [−4.0, −2.1]; −2.7 [−3.5, −1.8]). Relative performance output (Performance Index; 0–1000) negatively predicted sleep duration (r [95% CI]; −0.32 [−0.46, −0.17]) and sleep quality (−0.34 [−0.47, −0.19]) during the race. Temporal changes in, and associations between, sleep timing, perceived experience, and exercise function highlight the potential for sleep‐improvement strategies that enhance performance in naturalistic endurance sporting contexts.

Summary: Infant sleep problems have been associated with a myriad of adverse child and parent outcomes, yet whether these problems may pose a risk for parents on the road has received little research attention. This study sought to test whether mothers of infants with insomnia are at an elevated risk for vehicular crashes, by comparing their objectively measured driving performance with that of mothers of well‐sleeping infants and with that of women without children. Fifty‐four women from these three groups completed a simulated driving task. Outcome measures included standard deviation of lateral position, number of lane crossings, standard deviation of speed, average speed and maximum speed. Women additionally reported on their driving behaviour using the Driving Behaviour Questionnaire, and on sleep, sleepiness and insomnia symptoms using 7‐day sleep diaries and questionnaires. Mothers of infants with insomnia demonstrated greater lane deviation (Wald = 9.53, p = 0.009), higher maximum speed (Wald = 6.10, p = 0.04) and poorer self‐rated driving behaviour (Wald = 7.44, p = 0.02) compared with control groups. Analyses also indicated that driving performance in mothers of infants with insomnia tended to be poorer relative to control groups with the progression of time on task. While further research is needed to assess the scope of these effects, our findings suggest that parents, healthcare providers and policymakers should be aware of the potential consequences of infant sleep problems on road safety, and collaborate to establish strategies to mitigate these risks.