Sleep restriction by sleep timing late night or early wake: The impact on physical activity and dietary intake in adults

Isolated and Combined Effects of Moderate Normobaric Hypoxia and Sleep Restriction on Energy Intake and Food Reward

Hypoxia (HY) and sleep deprivation have opposite effects on appetite. As HY may alter sleep, it may be informative to assess the accumulative effects of these two stressors on hunger, energy intake (EI), and food reward. Seventeen young, active, healthy males completed four 5-hr sessions in normoxia (NO) or normobaric HY (FIO2 = 13.6%, ∼3,500 m) after a night of habitual sleep (HS; total sleep time >6 hr) or sleep restriction (SR; total sleep time <3 hr). Subjective appetite was assessed regularly using visual analogic scales and EI during an ad libitum lunch after 3.5 hr of exposure. Food reward was assessed using the Leeds Food Preference Questionnaire just before the lunch. As expected, EI was lower for the HY-HS (4.32 ± 0.71 MJ; p = .048) and HY-SR (4.16 ± 0.68 MJ, p = .013) sessions than the NO-HS (4.90 ± 0.84 MJ) session without acute mountain sickness-related gastrointestinal symptoms. No significant effect of SR alone was observed (NO-SR: 4.40 ± 0.68 MJ). Subjective appetite was not affected. Explicit liking for high-fat foods was higher with SR than HS (main effect: p = .002) and implicit wanting for high-fat foods was higher for the NO-SR, HY-HS, and HY-SR sessions than the NO-HS session (p < .006). Thus, acute SR did not modify subjective appetite or EI despite the increasing food reward for high-fat foods and did not alter the HY-induced changes of appetite or food reward.

Short Sleep Duration Disrupts Glucose Metabolism: Can Exercise Turn Back the Clock?

Short sleep duration is prevalent in modern society and may be contributing to type 2 diabetes prevalence. This review will explore the effects of sleep restriction on glycemic control, the mechanisms causing insulin resistance, and whether exercise can offset changes in glycemic control. Chronic sleep restriction may also contribute to a decrease in physical activity leading to further health complications.

Understanding the variation in exercise responses to guide personalized physical activity prescriptions

Understanding the factors that contribute to exercise response variation is the first step in achieving the goal of developing personalized exercise prescriptions. This review discusses the key molecular and other mechanistic factors, both extrinsic and intrinsic, that influence exercise responses and health outcomes. Extrinsic characteristics include the timing and dose of exercise, circadian rhythms, sleep habits, dietary interactions, and medication use, whereas intrinsic factors such as sex, age, hormonal status, race/ethnicity, and genetics are also integral. The molecular transducers of exercise (i.e., genomic/epigenomic, proteomic/post-translational, transcriptomic, metabolic/metabolomic, and lipidomic elements) are considered with respect to variability in physiological and health outcomes. Finally, this review highlights the current challenges that impede our ability to develop effective personalized exercise prescriptions. The Molecular Transducers of Physical Activity Consortium (MoTrPAC) aims to fill significant gaps in the understanding of exercise response variability, yet further investigations are needed to address additional health outcomes across all populations.