Introduction

Empirical, theoretical, and clinical focus on translational sleep science in behavioral medicine continues to expand. This second special issue focused on sleep science in the International Journal of Behavioral Medicine is a testament to the growth in behavioral sleep research. The impact of sleep on human health is more apparent than ever before. The entire global community has experienced the enormous burden of the COVID-19 pandemic. Adjustment to prolonged changes and limitations in everyday life has impacted individuals' professional, social, emotional, physical, spiritual, and financial well-being [1]. Such behavioral changes, significant stressors, and challenged coping processes have profoundly altered the patterns and quality of our sleep and have brought acute awareness of the overall influence of sleep on our quality of life. A research focus on sleep health is both timely and paramount.

It has been well documented that much of the world experiences deficits in sleep [2] and that sleep problems provide multiple pathways to the development and/or exacerbation of myriad mental and physical health maladies [3]. The field of behavioral medicine has been rising to the challenge of recognizing and defining the health impact of sleep disruption and developing effective behavioral approaches to improving sleep patterns and quality. Research included in this special issue reflects strong examples of work that highlights the continued discovery of the bidirectional effects of sleep on health behaviors and health-relevant outcomes.

A critical task in translating basic behavioral research to effective interventions and clinical treatments involves identifying the groups and populations at heightened risk for experiencing the deleterious impact of poor sleep, as well as the individual and systemic predictors and precursors that perpetuate sleep problems. Many of the articles in this issue reveal the impact of sleep within specific groups. There is a strong emphasis on examining sleep in student groups and young adults. Jensen and colleagues ([4]; this issue) document associations of sleep quality and healthy eating behaviors in a relatively large sample of young adults. Likewise, Nicholson and colleagues ([5]; this issue) similarly connect poorer sleep quality with higher body mass index in college students. In fact, college students may be particularly vulnerable to poor sleep with impact on academic outcomes, physical health, and risk behavior. In this issue, Hamilton K. and colleagues ([6]; this issue) use a theoretically grounded approach to examine predictors of college student sleep across two cultural contexts and Hamilton N. and colleagues ([7]; this issue) use diary methods to identify the complex, reciprocal relationships of sleep and academic performance. The paper by Komrij and colleagues ([8]; this issue) highlights the contextual and behavioral predictors of sleep in one of the first large longitudinal cohort studies of child sleep duration.

The present issue includes a set of articles that highlight cross-cutting issues, research questions, and methods in translational sleep science. Included articles illustrate work that spans major research areas theories and clinical applications. Papers in this issue span across a variety of important groups at risk for poor sleep or vulnerability to the effects of sleep disruptions, including pregnant women ([9]; this issue), military personnel ([10]; this issue), as well as identification of individuals at heightened risk for cancer ([11]; this issue), and disordered weight control ([12]; this issue), or with multiple medical co-morbidities ([13]; this issue).

This special series of IJBM highlights the significance and innovation of sleep research in behavioral medicine as well as the opportunities for future work and the public health importance of sleep to our collective health. The next decade will likely continue to grow and develop translational sleep science, and behavioral medicine will focus on filling critical gaps in sleep knowledge and clinical practice. With developments in this arena so will come comprehensive improvements in clinical treatment of sleep disorders, increased knowledge of the risk factors for and biobehavioral mechanisms of sleep disruption, innovation in measurement and research design, optimization in impact and delivery of intervention, and mitigation of related health epidemics (e.g., obesity, cardiovascular disease) that are affected by sleep health. Sleep well.