Sedentary work and participation in leisure-time physical activity.

OBJECTIVE: Demanding psychosocial work characteristics, such as high job demands, can have a detrimental impact on leisure-time physical activity (LTPA), with adverse consequences for employee health and well-being. However, the mechanisms and moderators of this crossover effect are still largely unknown. We therefore aimed to identify and test potential mediating and moderating factors from within and outside the work environment. Based on the previous research, we expected job demands to be negatively related to LTPA through fatigue. In addition, we expected that job control and worktime control would attenuate the relationship between job demands and fatigue. Furthermore, we hypothesized that autonomous exercise motivation and spontaneous action planning would attenuate the relationship between fatigue and LTPA. In addition to these cross-sectional hypotheses, we expected the same effects to predict a change in LTPA in the following year. METHODS: To investigate these assumptions, a preregistered longitudinal survey study was conducted among a large sample of Dutch employees in sedentary jobs. Participants reported on the constructs of interest in 2017 and 2018 (N = 1189 and 665 respectively) and the resulting data were analyzed using path analyses. RESULTS: Our cross-sectional analyses confirm a weak indirect, negative association between job demands and LTPA, via fatigue. However, this finding was not observed in our longitudinal analyses and none of the other hypotheses were confirmed. CONCLUSION: This study shows that, among employees with relatively healthy psychosocial work characteristics (i.e., high job control), the evidence for an impact of these work characteristics on participation in LTPA is limited.

Motivation counteracts fatigue-induced performance decrements in soccer passing performance.

Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players' motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.

Self-reported sleep quantity, quality and sleep hygiene in elite athletes.

Sleep is essential for recovery and performance in elite athletes. While actigraphy-based studies revealed suboptimal sleep in athletes, information on their subjective experience of sleep is scarce. Relatively unexplored is also the extent to which athletes' sleep is adversely affected by environmental conditions and daytime behaviours, that is sleep hygiene. This study aimed to provide insight in sleep quantity, quality and its putative association with sleep hygiene. Participants were 98 elite (youth) athletes competing at the highest (inter-)national level. Sleep quantity, quality and sleep hygiene were assessed once covering a 1-month period by using established (sub)clinical questionnaires, and repeatedly during 7 consecutive days. Sleep quality was generally healthy, although 41% of all athletes could be classified as 'poor sleeper', and 12% were identified as having a sleep disorder. Daily self-monitoring revealed sleep durations of 8:11 ± 0:45 h, but elevated wake after sleep onset of 13 ± 19 min. Sleep quality, feeling refreshed, and morning vigor were moderate at best. Regarding sleep hygiene, general measures revealed irregular sleep-wake patterns, psychological strain and activating pre-sleep behaviours. At the daily level, blue-light exposure and late-evening consumption of heavy meals were frequently reported. General sleep hygiene revealed significant associations with sleep quality (0.45 < r > 0.50; P < 0.001). Results indicate that there is ample room for optimization, specifically in onset latency and in wake after sleep onset. Subtle improvements in sleep seem possible, and optimizing sleep hygiene, such as regular sleep-wake patterns and reducing psychological strain, may facilitate this sleep upgrading process.

Effects of Natural Between-Days Variation in Sleep on Elite Athletes' Psychomotor Vigilance and Sport-Specific Measures of Performance.

Performance capacity in athletes depends on the ability to recover from past exercise. While evidence suggests that athletic performance decreases following (partial) sleep deprivation and increases following sleep extension, it is unclear to which extent natural variation in sleep impacts performance. Sleep quantity and, for the first time, sleep stages were assessed among 98 elite athletes on three non-consecutive nights within a 7-day monitoring period, along with performance tests that were taken on standardized times each following morning. Performance assessment included psychomotor performance (10-minute psychomotor vigilance task) and sport-specific tests of fine (e.g., accuracy) and gross motor skills (e.g., endurance, power). Mixed-effects models were employed to assess the effect of sleep quantity (total sleep time (TST), sleep onset latency (SOL), wake after sleep onset, sleep efficiency) and sleep stage duration (light, deep, REM) on performance. Average TST was 7:30 ± 1:05 hours, with a mean variation of 57 minutes across days. Longer TSTs were associated with faster reaction times (p = 0.04). Analyses indicated small and inconsistent effects of sleep quantity (TST, SOL) and sleep staging (light sleep) on gross motor performance, and no effects on fine motor skill performance. Results indicate that natural variation in sleep quantity impacts psychomotor vigilance to a greater extent than athletic performance. Small or absent effects can be a consequence of the rather small variation in non-manipulated sleep. It is suggested that one night of compromised sleep may not be immediately problematic, but that more extreme sleep loss or accumulated sleep debt may have more severe consequences.

The effect on sleep of being on-call: an experimental field study.

The aim of this study was to: (i) gain more insight into the relationship between being on-call and sleep and (ii) investigate the role of stress in this relationship. Data were collected by means of an experimental field study with a within-subject design (two conditions, random order). Ninety-six students participated during two consecutive nights: a reference night and a simulated on-call night without an actual call. Participants were told they could be called at any time during the on-call night. In the case of a call, participants had to perform online tasks for approximately 30 min. Self-reported sleep quality and the extent to which participants experienced stress during the on-call period were assessed by means of short questionnaires. Actigraphy was used to obtain objective sleep measures. Results for actigraphy data revealed no significant within-person differences between conditions. However, participants reported longer sleep onset latencies, more awakenings and more wake after sleep onset during the on-call night than during the reference night. They also reported more sleep problems and a lower overall sleep quality, and felt less recuperated after the on-call night. Perceived stress moderated the relationship between being on-call, on one hand, and the number of awakenings, wake after sleep onset, sleep problems and overall sleep quality, on the other hand. Results show that, even in the absence of an actual call, sleep during on-call nights is of lower quality and has less restorative value - especially when being on-call is experienced as stressful.

Disentangling longitudinal relations between physical activity, work-related fatigue, and task demands.

PURPOSE: This longitudinal study examined 'normal', 'reversed', and 'reciprocal' relationships between (1) physical activity and work-related fatigue; and (2) physical activity and task demands. Furthermore, the effects of across-time change in meaningful physical activity groups on levels of employees' work-related fatigue and task demands were studied. These groups were based on employees' compliance with the international physical activity norm. METHODS: Two waves with a one-year time lag of a national representative survey on the quality of work, health, and well-being among Dutch employees were used (N = 2275). Longitudinal effects were tested using Structural Equation Modelling. Meaningful physical activity groups were compared using group-by-time analysis of covariance. RESULTS: Support was found for reciprocal relations between physical activity and work-related fatigue. It was found that an increase in physical activity is associated with a decrease in work-related fatigue over time and that an increase in work-related fatigue is associated with a decrease in physical activity over time. No significant longitudinal relations were found between physical activity and task demands. Employees whose compliance with the physical activity norm changed over time showed fairly stable levels of work-related fatigue and task demands. CONCLUSIONS: The current findings provide evidence for the potential role of physical activity in the prevention and reduction in work-related fatigue. However, results also indicate that fatigued workers, who would benefit most from physical activity, are less physically active. Our results further indicate that relying on changes in compliance to the physical activity norm may not be the most suitable way to examine changes in work-related fatigue.

Efficacy of an exercise intervention for employees with work-related fatigue: study protocol of a two-arm randomized controlled trial.

BACKGROUND: The aim of the current study is to evaluate the efficacy of an exercise intervention to reduce work-related fatigue. Exercise is a potentially effective intervention strategy to reduce work-related fatigue, since it may enhance employees' ability to cope with work stress and it helps to detach from work. However, based on available research, no clear causal inferences regarding its efficacy can be made. This RCT therefore investigates whether exercise is effective in reducing work-related fatigue, and in improving other indicators of employees' mental and physical well-being and performance. METHODS/DESIGN: A two-arm parallel trial will be conducted. Participants (N = 108) who experience high levels of work-related fatigue will be randomized at a 1:1 ratio to a 6-week exercise intervention or wait list (control). The exercise intervention consists of three one-hour low-intensity outdoor running sessions a week. Each week, two sessions take place in a group under supervision of a trainer, and one session is completed individually. The running sessions will be carried out during leisure time. The primary outcome is work-related fatigue. Secondary outcomes include work ability, self-efficacy, sleep quality, cognitive functioning, and aerobic fitness. These data will be collected at pre-intervention, post-intervention, and at 6 weeks and 12 weeks after the intervention. In addition, weekly measures of employees' well-being, and exercise activities (i.e. type, frequency, and duration) and experiences (i.e. pleasure, effort, and detachment) will be collected during the intervention period. DISCUSSION: This study will compare an exercise intervention to a wait list. This enables us to examine the effect of exercise on work-related fatigue compared to the natural course of these symptoms. As such, this study contributes to a better understanding of the causal link between exercise and work-related fatigue. If the intervention is proven effective, the results could provide a basis for future 'effectiveness' trials in which the (implementation of the) intervention can be investigated among a broader defined population in a less standardized way, eventually leading to better evidence-based policies and practices to employees, employers, health practitioners, and policy makers concerning the effect of exercise on work-related fatigue. TRIAL REGISTRATION: NTR5034. Registered 10 March 2015.

Who gets fired, who gets re-hired: the role of workers' contract, age, health, work ability, performance, work satisfaction and employee investments.

PURPOSE: Many workers have been dismissed in the past few years, either becoming unemployed or finding re-employment. The current study examined whether dismissal and its follow-up for the employee (re-employment versus unemployment) could be predicted from workers' employment contract and age, and their health status, work ability, work performance, work satisfaction and employee investments at baseline. METHODS: Our sample comprised a selection of participants from the Netherlands Working Conditions Survey 2010 who participated in a follow-up questionnaire in 2012 (N = 2,644). We used logistic regression analyses to test our hypotheses. RESULTS: Temporary employment, low health status, low work ability, poor work performance, low work satisfaction and no employee investments in terms of training predicted future dismissal. Furthermore, older workers and workers reporting decreased work performance due to impaired health at baseline had a lower chance of re-employment after being dismissed. Interestingly, after taking into account all predictors, former temporary workers without permanent employment prospects had much better chances of re-employment after their dismissal than former permanent workers. CONCLUSIONS: Temporary, less healthy, low work ability, poor performing, dissatisfied and "under-invested" workers are at risk for dismissal, whereas older and less healthy workers are (also) at risk for long-term unemployment after being dismissed.

Music and psychophysiological recovery from stress.

OBJECTIVE: This experimental study examined whether listening to self-chosen music after stress exposure improves mood, decreases subjective arousal and rumination, and facilitates cardiovascular recovery. METHOD: Participants (N = 123) were exposed to a mental arithmetic task with harassment to induce stress. Afterward, participants were randomly assigned to one of four "recovery" conditions where they (1) listened to self-chosen relaxing music, (2) listened to self-chosen happy music, (3) listened to an audio book, or (4) sat in silence. After this 5-minute "recovery manipulation period," participants sat in silence for another 5 minutes. Systolic blood pressure, diastolic blood pressure, and heart rate were continuously measured. RESULTS: The recovery conditions caused differences in positive affect (F(3,119) = 13.13, p < .001) and negative affect (F(3,119) = 2.69, p = .049). As expected, mood improved while listening to either relaxing music or happy music. The conditions showed no differences in subjective arousal (F(3,117) = 2.03, p = .11) and rumination (F(3,119) = 1.10, p = .35). Systolic blood pressure recovery, however, differed between the conditions (linear time trend: F(3,116) = 4.50, p = .005; quadratic time trend: F(3,115) = 5.24, p = .002). Listening to both relaxing and happy music delayed systolic blood pressure recovery when compared with both control conditions. CONCLUSIONS: Listening to self-selected music is an effective mood enhancer, but it delays blood pressure recovery.

Cognitive performance in both clinical and non-clinical burnout.

Relatively little is known about cognitive performance in burnout. The aim of the present study was to further our knowledge on this topic by examining, in one study, cognitive performance in both clinical and non-clinical burnout while focusing on three interrelated aspects of cognitive performance, namely, self-reported cognitive problems, cognitive test performance, and subjective costs associated with cognitive test performance. To this aim, a clinical burnout patient group (n = 33), a non-clinical burnout group (n = 29), and a healthy control group (n = 30) were compared on self-reported cognitive problems, assessed by a questionnaire, as well as on cognitive test performance, assessed with a cognitive test battery measuring both executive functioning and more general cognitive processing. Self-reported fatigue, motivation, effort and demands were assessed to compare the different groups on subjective costs associated with cognitive test performance. The results indicated that the clinical burnout patients reported more cognitive problems than the individuals with non-clinical burnout, who in turn reported more cognitive problems relative to the healthy controls. Evidence for impaired cognitive test performance was only found in the clinical burnout patients. Relative to the healthy controls, these patients displayed some evidence of impaired general cognitive processing, reflected in slower reaction times, but no impaired executive functioning. However, cognitive test performance of the clinical burnout patients was related to larger reported subjective costs. In conclusion, although both the clinical and the non-clinical burnout group reported cognitive problems, evidence for a relatively mild impaired cognitive test performance and larger reported subjective cost associated with cognitive test performance was only found for the clinical burnout group.

How effective are organizational-level interventions in improving the psychosocial work environment, health, and retention of workers? A systematic overview of systematic reviews.

OBJECTIVE: This study aimed to systematically review the effectiveness of organizational-level interventions in improving the psychosocial work environment and workers' health and retention. METHODS: We conducted an overview of systematic reviews on organizational-level interventions published between 2000 and 2020. We systematically searched academic databases, screened reference lists, and contacted experts, yielding 27 736 records. Of the 76 eligible reviews, 24 of weak quality were excluded, yielding 52 reviews of moderate (N=32) or strong (N=20) quality, covering 957 primary studies. We assessed quality of evidence based on quality of review, consistency of results, and proportion of controlled studies. RESULTS: Of the 52 reviews, 30 studied a specific intervention approach and 22 specific outcomes. Regarding intervention approaches, we found strong quality of evidence for interventions focusing on "changes in working time arrangements" and moderate quality of evidence for "influence on work tasks or work organization", "health care approach changes", and "improvements of the psychosocial work environment". Regarding outcomes, we found strong quality of evidence for interventions about "burnout" and moderate quality evidence for "various health and wellbeing outcomes". For all other types of interventions, quality of evidence was either low or inconclusive, including interventions on retention. CONCLUSIONS: This overview of reviews identified strong or moderate quality of evidence for the effectiveness of organizational-level interventions for four specific intervention approaches and two health outcomes. This suggests that the work environment and the health of employees can be improved by certain organizational-level interventions. We need more research, especially about implementation and context, to improve the evidence.

Can labour contract differences in health and work-related attitudes be explained by quality of working life and job insecurity?

STUDY AIM: We hypothesise that due to a lower quality of working life and higher job insecurity, the health and work-related attitudes of temporary workers may be less positive compared to permanent workers. Therefore, we aimed to (1) examine differences between contract groups (i.e. permanent contract, temporary contract with prospect of permanent work, fixed-term contract, temporary agency contract and on-call contract) in the quality of working life, job insecurity, health and work-related attitudes and (2) investigate whether these latter contract group differences in health and work-related attitudes can be explained by differences in the quality of working life and/or job insecurity. METHODS: Data were collected from the Netherlands Working Conditions Survey 2008 (N = 21,639), and Hypotheses were tested using analysis of variance and cross-table analysis. RESULTS: Temporary work was associated with fewer task demands and lower autonomy and was more often passive or high-strain work, while permanent work was more often active work. Except for on-call work, temporary work was more insecure and associated with worse health and work-related attitude scores than permanent work. Finally, the quality of working life and job insecurity partly accounted for most contract differences in work-related attitudes but not in health. CONCLUSIONS: Especially agency workers have a lower health status and worse work-related attitudes. Job redesign measures regarding their quality of working life and job insecurity are recommended.

The effect of opportunity costs on mental fatigue in labor/leisure trade-offs.

Most people experience the feeling of mental fatigue on a daily basis. Previous research shows that mental fatigue impacts information processing and decision making. However, the proximal causes of mental fatigue are not yet well understood. In this research, we test the opportunity cost model of mental fatigue, which proposes that people become more fatigued when the next-best alternative to the current task is higher in value. In 4 preregistered experiments (N = 430), participants repeatedly reported their current level of fatigue and chose to perform a paid labor task versus an unpaid leisure task. In Study 1, all participants were offered the same labor/leisure choice. In Studies 2 and 3, we manipulated the opportunity costs of a labor task by varying the value of an alternative leisure task. In Study 4, we manipulated the opportunity costs of a labor task by varying the value of that labor task. In all studies, we found that people were more likely to choose for leisure as they became more fatigued. In Studies 2 through 4, we did not find that the manipulated leisure value influenced the amount of fatigue participants experienced nor the likelihood to choose for leisure. However, in exploratory analyses, in all studies, we found that participants who reported to value the leisure task more got more fatigued during labor and less fatigued during leisure. Collectively, these results provide cautious support for the opportunity cost model, but they also show that cost-benefit analyses relating to labor and leisure tasks are fleeting. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The impact of cognitive work demands on subsequent physical activity behavior.

After cognitively demanding work, individuals tend to be less physically active. However, the psychological mechanisms underlying this effect have not been thoroughly tested. The aim of this article was to experimentally investigate the impact of cognitive work demands on subsequent physical activity behavior. Across two preregistered experiments, participants were exposed to high or low levels of cognitive work demands, operationalized as workload in Experiment 1 and as working-memory load in Experiment 2. In a subsequent choice task, participants made binary consequential choices between leisure nonphysical activities (e.g., drawing) and effortful physical activities (e.g., cycling). Choice alternatives were matched on attractiveness rankings. Additionally, physical endurance performance was measured using a standardized cycling protocol in Experiment 1. In contrast to the hypotheses, after performing work with high cognitive demands, participants were not more likely to choose nonphysical over physical activities nor did they perform significantly worse on the physical endurance task. Exploratory analyses suggest that preexisting preferences for either physical or nonphysical activities explained physical activity behavior above and beyond exposure to cognitively demanding work. These experiments question the impact of cognitively demanding work on subsequent cognitive fatigue and physical activity behavior. Implications for theory, practice, and future directions are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Investigating the associations among overtime work, health behaviors, and health: a longitudinal study among full-time employees.

BACKGROUND: It has often been suggested that high levels of overtime lead to adverse health outcomes. One mechanism that may account for this association is that working overtime leads to elevated levels of stress, which could affect worker's behavioral decisions or habits (such as smoking and lack of physical activity). In turn, this could lead to adverse health. PURPOSE: The present study examined this reasoning in a prospective longitudinal design. Data from the prospective 2-year Study on Health at Work (N = 649) were used to test our hypotheses. METHODS: Structural equation analysis was used to examine the relationships among overtime, beneficial (exercising, intake of fruit and vegetables) and risky (smoking and drinking) health behaviors, and health indicators (BMI and subjective health). RESULTS: Working overtime was longitudinally related with adverse subjective health, but not with body mass. Moreover, working overtime was associated with lower levels of physical activity and intake of fruit and vegetables, but not with smoking and drinking. Finally, higher levels of risky and lower levels of beneficial health behaviors were longitudinally associated with ill health. CONCLUSIONS: The relation between overtime and ill health is partly accounted for by the unhealthy lifestyle in which overworkers tend to engage. However, a direct longitudinal effect of overtime on health suggested that the effects of overtime on health may also partly be due to the sustained physiological activation that results from working overtime. Whereas working a moderate amount of overtime does not usually entail major health risks, these will increase with increasing overtime.

Costs and benefits of autonomy when learning a task: an experimental approach.

Previous findings suggested that the positive relationship between autonomy and learning outcomes (such as improved task performance) only holds up until a certain optimum level of autonomy has been reached. This assumption was investigated in an experimental study where 95 participants had to learn a computer task. During the learning phase, we manipulated autonomy, distinguishing among no, moderate, and full autonomy. The results revealed that, when learning a task, having autonomy is preferred to having no autonomy. However, increases in autonomy beyond a certain level (i.e., full versus moderate autonomy) will not yield additional advantages regarding the motivation to learn and learning outcomes, and may have disadvantages in terms of learning efficiency.

Labor/leisure decisions in their natural context: The case of the smartphone.

In this research, we attempt to understand a common real-life labor/leisure decision, i.e., to perform cognitive work or to interact with one's smartphone. In an ecologically valid experiment, participants (N = 112) could freely switch back and forth between doing a 2-back task and interacting with their own smartphone. We manipulated the value of the 2-back task (by varying the value of monetary rewards; within-subjects) and of the smartphone (by switching on and off airplane mode; within-subjects) while we recorded incoming notifications, such as text messages. Our study produced three main findings: (1) the current value of the smartphone did not increase our statistical model's ability to predict switches from labor to leisure when the current task value was also taken into account; (2) however, participants reacted strongly to naturally incoming notifications, which were the strongest predictor of labor-to-leisure switches; (3) there was no evidence that taking into account individual differences (in the value assigned to labor and leisure) improved the model's ability to predict labor-leisure switches. In sum, using a situated approach to studying labor/leisure decisions, our findings highlight the importance of high task motivation, as well as the temporary distractive potential of smartphone notifications, when people face the challenge of staying focused on their productive tasks.

Fatigue, boredom and objectively measured smartphone use at work.

Nowadays, many people take short breaks with their smartphone at work. The decision whether to continue working or to take a smartphone break is a so-called labour versus leisure decision. Motivational models predict that people are more likely to switch from labour (work) to leisure (smartphone) the more fatigue or boredom they experience. In turn, fatigue and boredom are expected to decrease after the smartphone was used. However, it is not yet clear how smartphone use at work relates to fatigue and boredom. In this study, we tested these relationships in both directions. Participants (n = 83, all PhD candidates) reported their current level of fatigue and boredom every hour at work while an application continuously logged their smartphone use. Results indicate that participants were more likely to interact with their smartphone the more fatigued or bored they were, but that they did not use it for longer when more fatigued or bored. Surprisingly, participants reported increased fatigue and boredom after having used the smartphone (more). While future research is necessary, our results (i) provide real-life evidence for the notion that fatigue and boredom are temporally associated with task disengagement, and (ii) suggest that taking a short break with the smartphone may have phenomenological costs.

The Impact of Cognitive and Physical Effort Exertion on Physical Effort Decisions: A Pilot Experiment.

Research suggests that cognitive fatigue has a negative impact on physical activity participation. However, the mechanisms underlying this effect are yet unclear. Using an effort-based decision-making paradigm, we examined whether individuals weigh physical effort-costs more strongly when they are cognitively or physically fatigued. Twenty university students visited the lab on three occasions. On each visit, participants underwent a manipulation that was designed to either induce cognitive fatigue (i.e., 2-back task), physical fatigue (i.e., handgrip exercise), or served as a control condition (i.e., documentary watching). After the manipulations, participants performed an effort-based decision-making task in which they decided for 125 offers whether they accepted the offer to exert the required level of physical effort to obtain rewards that varied in value. The probability to accept offers declined with increasing effort requirements whereas the general probability to accept offers was not reduced by any of the experimental conditions. As expected, the decline in accepted offers with increasing effort requirements was stronger after prolonged exertion of physical effort compared to the control condition. Unexpectedly, this effect was not found after exerting cognitive effort, and exploratory analyses revealed that the impact of physical effort exertion on physical effort-based decisions was stronger than that of cognitive effort exertion. These findings suggest that people weight future physical effort-costs more strongly after exerting physical effort, whereas we could not find any evidence for this after exerting cognitive effort. We discuss multiple explanations for this discrepancy, and outline possibilities for future research.

Dim light, sleep tight, and wake up bright - Sleep optimization in athletes by means of light regulation.

Despite an elevated recovery need, research indicates that athletes often exhibit relatively poor sleep. Timing and consolidation of sleep is driven by the circadian system, which requires periodic light-dark exposure for stable entrainment to the 24-hour day, but is often disturbed due to underexposure to light in the morning (e.g. low-level indoor lighting) and overexposure to light in the evening (e.g. environmental and screen-light). This study examined whether combining fixed sleep schedules with light regulation leads to more consolidated sleep. Morning light exposure was increased using light-emitting goggles, whereas evening light exposure was reduced using amber-lens glasses. Using a within-subject crossover design, twenty-six athletes (14 female, 12 male) were randomly assigned to start the intervention with the light-regulation-week or the no light-regulation-week. Sleep was monitored by means of sleep diaries and actigraphy. Due to low protocol adherence regarding the fixed sleep-wake schedules, two datasets were constructed; one including athletes who kept a strict sleep-wake schedule (N = 8), and one that also included athletes with a more lenient sleep-wake schedule (N = 25). In case of a lenient sleep-wake schedule, light regulation improved self-reported sleep onset latency (Δ SOL = 8 min). This effect was stronger (Δ SOL = 17 min) and complemented by enhanced subjective sleep quality in case of a strict sleep-wake schedule. None of the actigraphy-based estimates differed significantly between conditions. To conclude, light regulation may be considered a potentially effective strategy to improve subjective sleep, but less obtrusive methods should be explored to increase protocol compliance.