Replacing sedentary time with physical activity or sleep: effects on cancer-related cognitive impairment in breast cancer survivors

Abstract

BackgroundEvidence suggests reallocating daily sedentary time to physical activity or sleep confers important health benefits in cancer survivors. Despite emerging research suggesting physical activity as a treatment for cancer-related cognitive impairment (CRCI), little is known about the interactive effects of behaviors across the 24-h period. The present purpose was to examine the cognitive effects of reallocating sedentary time to light-intensity physical activity, moderate-to-vigorous physical activity (MVPA), or sleep in breast cancer survivors.MethodsBreast cancer survivors (N = 271, Mage = 57.81 ± 9.50 years) completed iPad-based questionnaires and cognitive tasks assessing demographics, health history, executive function, and processing speed (Task-Switch, Trail Making). Participants wore an accelerometer for seven consecutive days to measure their sedentary, physical activity, and sleep behaviors. Single effects (each behavior individually) and partition (controlling for other behaviors) models were used to examine associations among behaviors and cognitive performance. Isotemporal substitution models were used to test the cognitive effects of substituting 30 min of sedentary time with 30 min of light-intensity activity, MVPA, and sleep.ResultsMVPA was associated with faster Task-switch reaction time in the partition models (stay: B = − 35.31, p = 0.02; switch: B = − 48.24, p = 0.004). Replacing 30 min of sedentary time with 30 min of MVPA yielded faster reaction times on Task-Switch stay (B = − 29.37, p = 0.04) and switch (B = − 39.49, p = 0.02) trials. In Trails A single effects models, sedentary behavior was associated with faster completion (B = − 0.97, p = 0.03) and light-intensity activity with slower completion (B = 1.25, p = 0.006). No single effects were observed relative to Trails B completion (all p > 0.05). Only the effect of MVPA was significant in the partition models (Trails A: B = − 3.55, p = 0.03; Trails B: B = − 4.46, p = 0.049). Replacing sedentary time with light-intensity activity was associated with slower Trails A (B = 1.55 p = 0.002) and Trails B (B = 1.69, p = 0.02) completion. Replacing light activity with MVPA yielded faster Trails A (B = − 4.35, p = 0.02) and Trails B (B = − 5.23, p = 0.03) completion.ConclusionsFindings support previous research suggesting MVPA may be needed to improve cognitive function in breast cancer survivors. Trails findings underscore the need to dissect sedentary contexts to better understand the impact of daily behavioral patterns on CRCI. Additional research investigating the cognitive impacts of behaviors across the 24-h period is warranted.Trial registrationThis study is registered with United States ClinicalTrials.gov (NCT02523677; 8/14/2015).Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4603-3) contains supplementary material, which is available to authorized users.

Effects of reallocating sedentary time with physical activity on quality of life indicators in breast cancer survivors

“…Boyle and colleagues found a significantly lower body mass index and waist circumference when reallocating sleep, sedentary time, or LPA to MVPA . Ehlers et al examined the effect of reallocation of sedentary time on cognitive function, finding reallocation of time to MVPA was significantly associated with better cognitive performance . Collectively, our results and results from previous research demonstrate there are multiple health‐related benefits for breast cancer survivors of replacing sitting time with MVPA and provide evidence for the importance of future research investigating additional objective measures of health outcomes (ie, physical functioning, fitness, and biomarkers) using isotemporal substitution models.…”

“…Two other studies have used isotemporal substitution in breast cancer survivors . Boyle and colleagues found a significantly lower body mass index and waist circumference when reallocating sleep, sedentary time, or LPA to MVPA .…”

“…Findings indicate substitution of sitting behaviors with more active behaviors (standing, LPA, etc) was significantly associated with improved QOL and reduced fatigue in colorectal and non‐Hodgkin lymphoma cancer survivors, respectively. While isotemporal substitution has been used in breast cancer survivors to illustrate the benefit of replacing time spent sedentary with time spent in MVPA on body mass index, waist circumference, and cognitive impairment, to our knowledge, no study has used isotemporal substitution to examine QOL in breast cancer survivors, the largest group of cancer survivors in the United States . The purpose of this study was to determine the effect of substituting time between sedentary and active behaviors on QOL indicators in breast cancer survivors.…”

Using Isotemporal Analyses to Examine the Relationships Between Daytime Activities and Cancer Recurrence Biomarkers in Breast Cancer Survivors

“…These isotemporal results are consistent with findings from previous studies among breast cancer survivors that reported estimated benefits in reallocating time to MVPA. 29,30 In a sample of 256 breast cancer survivors, Boyle et al 30 found a 30-minute reallocation of SB or LIPA to MVPA was associated with lower self-reported waist circumference and BMI. Current lifestyle treatment plans for breast cancer survivors encourage achieving 30 minutes of daily PA and meeting weekly PA guidelines (150 min of MVPA a week) 5 ; however, our findings add to the literature by demonstrating that even an 18-minute shift, or 1 SD, from SB or LIPA to MVPA may have beneficial associations for breast cancer survivors.…”

“…Recent isotemporal studies in breast cancer survivor populations suggest it is worthwhile to move beyond examining daily activities independently and start to explore how time spent in activities throughout the day is associated to health. 29,30 The primary aim of this study is to use accelerometer data to construct isotemporal substitution models to assess the associations to cancer recurrence biomarkers of reallocating time spent in SB, LIPA, and MVPA in a sample of postmenopausal breast cancer survivors. The goal of these analyses is to explore how the reallocation of time spent in daytime activities may be beneficial to markers of breast cancer recurrence.…”