The research, conducted by Johanna Edvinsson, Svend Erik Mathiassen, and David M. Hallman at the University of Gävle in Sweden, addressed a growing paradox in modern knowledge work. Flexible work arrangements, which allow employees to decide when and where they work, are widely promoted as a route to better work-life balance. Yet a substantial body of evidence indicates that flexibility cuts both ways. When the boundary between office and home dissolves, so does the psychological signal that work is finished. An always-on culture can emerge within workgroups, in which employees feel obligated to answer messages late into the evening, extend their working days, and sacrifice both physical activity and sleep. Previous studies have linked this blurring of boundaries to exhaustion, poorer sleep quality, and an elevated need for recovery.

Recovery, in the occupational health literature, refers to the unwinding processes through which strain accumulated during work returns to its baseline level. Psychological detachment, the subjective experience of switching off and leaving work behind, is considered central to this process, particularly in mentally demanding desk jobs. Meta-analyses have associated stronger detachment with less exhaustion, better well-being, and better sleep. But most intervention research in this field has relied on self-reported outcomes, and few studies have asked whether workplace programs can change objectively measured, around-the-clock behavior patterns or the physiology of recovery during sleep. The Swedish team set out to fill that gap with hard measurement data rather than questionnaires alone.

The intervention itself emerged from a co-creation process involving employees, employer representatives, and researchers within a large Swedish governmental agency. Rather than imposing a top-down wellness program, the researchers drew on a comprehensive questionnaire distributed to roughly 4,900 employees and on focus group interviews across all divisions of the organization to identify what workers actually needed. Two activities resulted. The first was an individual-level course, delivered to small groups, that trained participants in using digital tools to plan and prioritize work, minimize interruptions, and end the day with a sense of control. The second was a workgroup-level workshop in which colleagues and managers jointly developed common rules and routines for flexible work, such as how to signal availability to colleagues and what to expect about responding to work communication outside regular hours. Approximately 94 percent of eligible employees took the course and 82 percent attended the workshops, and about a third of workshop participants reported continuing to work on their action plans afterward.

The study used a quasi-experimental design with two departments in the same organizational division, one receiving the intervention and one serving as a control. Twenty-seven intervention participants and 21 controls completed baseline measurements, and 42 of them were followed up twelve months later. Each participant wore a thigh-mounted ActiGraph accelerometer for three consecutive days while also wearing a Firstbeat heart rate monitor that recorded beat-to-beat heart intervals. Sleep periods were identified from diaries, and waking time was classified into active behaviors such as walking, cycling, and stair climbing, versus inactive behaviors such as sitting, lying, and standing. Because the 24-hour day is a fixed budget in which every behavior competes with every other, the team analyzed the data using compositional data analysis, computing isometric log-transformed ratios that capture sleep relative to time awake and, within waking hours, activity relative to inactivity.

The headline result concerned sleep. In the intervention group, nightly sleep rose from an average of 376 minutes at baseline to 412 minutes at follow-up, an increase of 36 minutes that lifted sleep from 26.1 percent to 28.6 percent of the 24-hour day. The control group moved in the opposite direction, dropping from 416 to 393 minutes. Statistical testing confirmed that the difference in change between groups was robust, with a large effect size for the sleep-versus-wake ratio that grew even stronger after adjusting for age, sex, body mass index, and whether participants had children at home. The authors note that the magnitude of the gain is striking when compared against clinical benchmarks: a meta-analysis of randomized trials found that melatonin, a standard treatment for primary sleep disorders, produces sleep-duration improvements of only 5 to 25 minutes. The intervention group’s new average of nearly seven hours per night brought participants meaningfully closer to the seven to nine hours recommended for adults.

Not every outcome moved in the same direction. The intervention did not significantly change the balance of physical activity relative to inactivity during waking hours, and it did not improve heart rate variability during sleep, the study’s physiological marker of recovery. Heart rate variability reflects the interplay between the sympathetic and parasympathetic branches of the autonomic nervous system, with higher values during sleep, particularly the RMSSD and SDNN metrics, indicating greater parasympathetic activity and more efficient physiological restoration. The researchers offer several possible explanations. The intervention was designed to change work practices rather than autonomic regulation directly; physiological adaptations may simply require more time than twelve months of follow-up captured; and the small sample, combined with considerable day-to-day variability in heart rate variability between individuals, may have masked a small but genuine effect. The extra sleep also appears to have displaced both active and inactive waking time in roughly equal proportion, leaving the activity-to-inactivity ratio essentially unchanged.

The findings dovetail with a companion publication from the same project showing that the intervention improved self-reported psychological detachment and reduced the need for recovery, particularly among employees who began the study with the highest recovery needs. Taken together, the two studies suggest that the program successfully supported psychological and behavioral dimensions of recovery, with longer sleep as its clearest objective signature, but that these changes were not sufficient to shift physiological recovery as indexed by cardiac autonomic function. The authors suggest that future interventions aiming at physiological outcomes might incorporate explicit relaxation components, such as mindfulness training, slow breathing exercises, or biofeedback, which previous research has linked to improvements in heart rate variability, alongside the organizational and individual strategies tested here.

The study has limitations that the authors acknowledge candidly. Participants were not randomized to groups, because the intervention had to be scheduled around organizational constraints, and the two departments, although geographically separated, belonged to the same division, leaving open the possibility of contamination through informal conversation. The sample was small, sleep periods were identified from self-reported diaries rather than objective sleep staging, and three days of measurement, while sufficient for reliable estimates of most physical behaviors, cannot capture every nuance of sleep quality, nighttime awakenings, or daytime napping. The co-creation process that made the intervention relevant and feasible in this particular agency may also limit generalizability to other occupational settings.

Even so, the implications are considerable for the millions of knowledge workers now operating under flexible or hybrid arrangements. The results indicate that interventions targeting both individual work practices and collective workgroup norms, developed participatively with the people who must live with them, can produce measurable, clinically meaningful gains in sleep duration over a full year. As employers worldwide grapple with the health consequences of digitalized, boundary-free work, this Swedish experiment offers a concrete template: teach workers to manage their tools and priorities, and let teams negotiate shared rules about availability, and the 24-hour distribution of rest may rebalance itself toward recovery. Longer-term studies with larger samples, additional biomarkers such as cortisol and blood pressure, and richer sleep assessment will be needed to determine whether the behavioral gains translate into physiological and health benefits, but the demonstration that workplace design can add half an hour of sleep per night is, by itself, a result worth losing sleep over.

Subject of Research: Effects of a co-created workplace intervention on sleep, 24-hour physical behaviors, and heart rate variability in office workers with flexible work arrangements.

Article Title: Effects on 24-h physical behaviors and heart rate variability during sleep of a co-created workplace intervention to promote recovery in office workers with flexible work

Article References: Edvinsson, J., Mathiassen, S. E., & Hallman, D. M. (2026). Effects on 24-h physical behaviors and heart rate variability during sleep of a co-created workplace intervention to promote recovery in office workers with flexible work. Journal of Activity, Sedentary and Sleep Behaviors, 5(1), Article 14. https://doi.org/10.1186/s44167-026-00107-0

Image Credits: AI Generated

DOI: 10.1186/s44167-026-00107-0

Keywords: flexible work, workplace intervention, sleep, recovery, heart rate variability, physical activity, sedentary behavior, office workers, occupational health, co-creation, compositional data analysis, psychological detachment

The analytical framework behind the study rests on two well-established pillars of organizational psychology. The first is social identity theory, originally formulated by Henri Tajfel and John Turner, which holds that people categorize themselves and others into in-groups and out-groups and then favor their own group in subtle but measurable ways. In the workplace, age functions as a powerful social identity: younger and older employees form implicit cohorts, attach stereotypes to each cohort, and interpret the same organizational events through those stereotype-tinted lenses. The second pillar is the concept of organizational climate, the shared perception employees hold about the policies, practices, and behaviors that are rewarded and expected in their organization. Prior research has shown that when the climate is inclusive of age, diversity tends to improve performance; when it is not, diversity can degrade cooperation and trust. Bennett’s study tests whether these theoretical predictions hold when younger and older American workers are asked directly about their lived experiences.

The headline finding is a strikingly symmetric perceptual divide. Older workers, those aged 50 and above, report experiencing age-based disadvantage more frequently than their younger colleagues. They describe being passed over, patronized, or assumed to lack technological fluency, consistent with a long line of research documenting ageist stereotypes that cast older employees as less adaptable, less trainable, and less valuable to invest in. Yet the same older workers are markedly more supportive of the idea that older employees should remain in the workforce for as long as they wish. In other words, the group that suffers most from age bias is also the group most committed to extended working lives, a combination that suggests older workers see continued employment as both an economic necessity and a source of identity and purpose, even while they acknowledge the friction it generates.

Younger workers tell a different story. Rather than reporting age-based exclusion, they express greater anxiety about delayed promotions and stalled career progression, a concern that researchers have long linked to perceived resource scarcity between generations. When senior positions remain occupied by employees working into their late sixties and seventies, younger workers may interpret the bottleneck as unfair competition, a dynamic documented in earlier work on intergenerational tension and subtle older-worker exclusion. The study’s results give this concern empirical weight in a nationally representative sample: younger respondents were significantly more likely than older respondents to worry that extended careers for their seniors would slow their own advancement up the organizational ladder.

A second major axis of divergence involves flexible work arrangements. Younger employees in the survey reported considerably higher engagement with flexible options, including remote work, adjustable schedules, and compressed hours, reflecting what the author characterizes as a generational shift in workplace norms rather than a simple difference in individual preference. This finding aligns with a broader body of research showing that flexibility practices interact with employee age in complex ways. Studies of hybrid and remote work have found productivity gains under geographic flexibility, while reviews of working-at-home effects note that older workers experience the health and social consequences of remote arrangements differently from younger ones. The survey data suggest that organizations offering flexibility primarily in formats designed around younger workers’ lives may unintentionally signal that these benefits belong to one cohort, reinforcing the very in-group boundaries that age-diversity programs aim to dissolve.

Perhaps the most consequential conclusion of the study is a caution against the popular corporate assumption that age diversity is automatically good for business. The analysis underscores that age diversity is not inherently beneficial; its impact depends on inclusion, climate, and proactive management. This echoes a substantial experimental and meta-analytic literature. Research on age-diversity climate has shown that age-inclusive human resource practices and the attitudes of senior leaders predict firm-level performance outcomes, while studies of age discrimination climates find negative performance consequences when bias goes unaddressed. Broader meta-analyses of workplace diversity similarly conclude that demographic differences translate into positive outcomes only under specific conditions, such as task relevance, supportive leadership, and open communication climates. The new survey results bring these laboratory and firm-level findings into the realm of ordinary workers’ perceptions, showing that the conditions for success are not yet widely met in the United States.

The practical implications for human resource leaders are concrete. Bennett points to bias-reduction strategies, inclusive flexibility policies, and cross-generational mentoring as the three most promising levers for converting potential intergenerational friction into collaborative advantage. Bias-reduction efforts draw on the intergroup contact tradition, which demonstrates through decades of meta-analysis that structured, cooperative contact between groups reduces prejudice, particularly when it unfolds under equal status and with institutional support. Mentoring programs that run in both directions, pairing older workers’ institutional knowledge with younger workers’ technological fluency, operationalize this contact principle while directly attacking the competence and warmth stereotypes that social psychology has shown people attach to both ends of the age spectrum. Inclusive flexibility, meanwhile, ensures that flexible arrangements are designed and marketed to workers of every age, preventing benefits from being coded as the property of a single generation.

The study is notable for its methodological position as one of the first nationally representative analyses to directly compare younger and older U.S. workers’ perceptions of age-related disadvantage and flexible work adoption, addressing what the author identifies as a critical gap in organizational psychology and aging research. Much of the existing evidence comes from single-firm samples, convenience surveys of older workers alone, or European datasets whose labor-market institutions differ substantially from the American context. By testing four formal hypotheses about generational differences in workplace perceptions against nationally representative data, the study provides a benchmark that future research can replicate and extend. At the same time, the cross-sectional design of the 2019 survey means the findings capture a snapshot rather than a trajectory, and the dichotomy between workers under and over 50 inevitably smooths over differences within each broad group.

Looking forward, the study closes by charting an ambitious research agenda: longitudinal designs that track how perceptions evolve as cohorts age, multi-level models that connect individual attitudes to team and organizational outcomes, and cross-cultural comparisons that test whether the American pattern of generational perception holds in societies with different retirement norms and cultural attitudes toward aging. The stakes of this agenda are rising. Labor force projections indicate that older workers will remain a growing share of the American workforce for decades, driven by longer life expectancy, changes to retirement security, and the shifting composition of available jobs. As the demographic reality of the five-generation workplace solidifies, the question is no longer whether organizations will be age-diverse but whether they will manage that diversity deliberately. The evidence from the 2019 Working Longer Survey suggests that without intentional effort, the default outcome is a workplace divided by silent, mutually reinforcing stereotypes, with older workers feeling sidelined and younger workers feeling stuck. With it, the same demographic mix could become a source of complementary skills, durable knowledge transfer, and genuine competitive advantage.

Subject of Research: Perceptions of age diversity and generational differences among younger and older U.S. workers based on the 2019 Working Longer Survey.

Article Title: Age Diversity and Workplace Perceptions: Insights from the 2019 Working Longer Survey

Article References: Bennett, J. (2026). Age Diversity and Workplace Perceptions: Insights from the 2019 Working Longer Survey. Trends in Psychology. https://doi.org/10.1007/s43076-026-00529-4

Image Credits: AI Generated

DOI: 10.1007/s43076-026-00529-4

Keywords: age diversity, workplace perceptions, generational differences, ageism, flexible work, organizational climate, social identity theory, aging workforce, inclusion, extended working lives, Diversity, Workplace