Affective reactions to real-life stressors and the role of physical activity in sports students - An Ambulatory Assessment study.

Students are exposed to a variety of stressors that can negatively affect their health and performance. Using an Ambulatory Assessment approach, this study investigated whether and how positive affect (PA) and negative affect (NA) changed in response to real-life stressors in sports students. In addition, the study investigated how physical activity (PhyA) moderated affective reactions to stressors. 62 participants of a German university (m = 23, f = 38, d = 1; age: M = 21.55 years, SD = 2.47) reported their daily stressors, affective states and PhyA (context, intensity and duration) six times per day via smartphone over five days (30 prompts per participants). To test the hypotheses multilevel models were calculated. Stressor context predicted affective reactions. PA was lower and NA was higher when general (financial problems) or academic (exam periods) stressors were reported. General PhyA had a positive effect on sports students affect (higher PA, lower NA). However, when PhyA was performed in exercise classes within their study program and a stressor was reported, PA decreased. The results showed that certain stressors interact negatively with affective states. Furthermore, the results suggested that PhyA, depending on the context where it occurred, may also induce negative affective changes in this target group of sport students. More studies need to examine how PhyA moderates affective reactions to stressors and examine the influences of context specific PhyA (e.g., type of PhyA) in more detail.

Quality Evaluation of Free-living Validation Studies for the Assessment of 24-Hour Physical Behavior in Adults via Wearables: Systematic Review.

BACKGROUND: Wearable technology is a leading fitness trend in the growing commercial industry and an established method for collecting 24-hour physical behavior data in research studies. High-quality free-living validation studies are required to enable both researchers and consumers to make guided decisions on which study to rely on and which device to use. However, reviews focusing on the quality of free-living validation studies in adults are lacking. OBJECTIVE: This study aimed to raise researchers' and consumers' attention to the quality of published validation protocols while aiming to identify and compare specific consistencies or inconsistencies between protocols. We aimed to provide a comprehensive and historical overview of which wearable devices have been validated for which purpose and whether they show promise for use in further studies. METHODS: Peer-reviewed validation studies from electronic databases, as well as backward and forward citation searches (1970 to July 2021), with the following, required indicators were included: protocol must include real-life conditions, outcome must belong to one dimension of the 24-hour physical behavior construct (intensity, posture or activity type, and biological state), the protocol must include a criterion measure, and study results must be published in English-language journals. The risk of bias was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool with 9 questions separated into 4 domains (patient selection or study design, index measure, criterion measure, and flow and time). RESULTS: Of the 13,285 unique search results, 222 (1.67%) articles were included. Most studies (153/237, 64.6%) validated an intensity measure outcome such as energy expenditure. However, only 19.8% (47/237) validated biological state and 15.6% (37/237) validated posture or activity-type outcomes. Across all studies, 163 different wearables were identified. Of these, 58.9% (96/163) were validated only once. ActiGraph GT3X/GT3X+ (36/163, 22.1%), Fitbit Flex (20/163, 12.3%), and ActivPAL (12/163, 7.4%) were used most often in the included studies. The percentage of participants meeting the quality criteria ranged from 38.8% (92/237) to 92.4% (219/237). On the basis of our classification tree to evaluate the overall study quality, 4.6% (11/237) of studies were classified as low risk. Furthermore, 16% (38/237) of studies were classified as having some concerns, and 72.9% (173/237) of studies were classified as high risk. CONCLUSIONS: Overall, free-living validation studies of wearables are characterized by low methodological quality, large variability in design, and focus on intensity. Future research should strongly aim at biological state and posture or activity outcomes and strive for standardized protocols embedded in a validation framework. Standardized protocols for free-living validation embedded in a framework are urgently needed to inform and guide stakeholders (eg, manufacturers, scientists, and consumers) in selecting wearables for self-tracking purposes, applying wearables in health studies, and fostering innovation to achieve improved validity.

Ambulatory Assessment for Physical Activity Research: State of the Science, Best Practices and Future Directions.

Technological and digital progress benefits physical activity (PA) research. Here we compiled expert knowledge on how Ambulatory Assessment (AA) is utilized to advance PA research, i.e., we present results of the 2nd International CAPA Workshop 2019 "Physical Activity Assessment - State of the Science, Best Practices, Future Directions" where invited researchers with experience in PA assessment, evaluation, technology and application participated. First, we provide readers with the state of the AA science, then we give best practice recommendations on how to measure PA via AA and shed light on methodological frontiers, and we furthermore discuss future directions. AA encompasses a class of methods that allows the study of PA and its behavioral, biological and physiological correlates as they unfold in everyday life. AA includes monitoring of movement (e.g., via accelerometry), physiological function (e.g., via mobile electrocardiogram), contextual information (e.g., via geolocation-tracking), and ecological momentary assessment (EMA; e.g., electronic diaries) to capture self-reported information. The strengths of AA are data assessment that near realtime, which minimizes retrospective biases in real-world settings, consequentially enabling ecological valid findings. Importantly, AA enables multiple assessments across time within subjects resulting in intensive longitudinal data (ILD), which allows unraveling within-person determinants of PA in everyday life. In this paper, we show how AA methods such as triggered e-diaries and geolocation-tracking can be used to measure PA and its correlates, and furthermore how these findings may translate into real-life interventions. In sum, AA provides numerous possibilities for PA research, especially the opportunity to tackle within- subject antecedents, concomitants, and consequences of PA as they unfold in everyday life. In-depth insights on determinants of PA could help us design and deliver impactful interventions in real-world contexts, thus enabling us to solve critical health issues in the 21st century such as insufficient PA and high levels of sedentary behavior.

Stress in Physical Education Teachers: A Systematic Review of Sources, Consequences, and Moderators of Stress.

Purpose: The purpose of this systematic review was to identify sources of stress, consequences of chronic stress and moderators of stress in physical education teachers and to formulate implications for future research and teacher education. Methods: The initial search identified 2483 publications, including 47 that met the inclusion criteria. Results: The most important sources of stress in physical education teachers were the curriculum, inadequate facilities/equipment, the low status of PE and students´ discipline problems. Regarding the consequences of chronic stress, the majority of studies assessed burnout and reported low to moderate levels of burnout in general. However, of the studies that reported percentages, 20-25% of physical education teachers indicated high levels of burnout. Conclusions: Regarding the relationship between sources of stress and consequences of chronic stress in physical education teachers, future studies should (a) take into account the whole stress process (b) use more adequate measures for stress and (c) address potential moderators of stress. In terms of practical implications, PE teachers should receive an adequate pre- and in-service training that aims at being aware of the main sources of stress in PE teachers and building up adequate coping strategies. In addition, PE teacher education should consider interventions to prevent health consequences of stress such as voice disorders.