BACKGROUND:This abstract provides a brief blueprint for a doctoral thesis that is connected to the national doctoral program Sustainable movement education (SMOVE) and research project MoveEarly.

INTRODUCTION:There are overwhelming evidence for the numerous positive health benefits of physical activity (PA).^1,2,3,4,5 Meanwhile, it is well known that PA-levels are insufficient in European and Swedish children alike.^6,7,8 Insufficient PA-levels is a substantial societal challenge since being of concern to the immediate and future development, health and well-being of children^9,10  as well as being of great economic burden to society^11,12.  Several policymakers, such as the World Health Organization (WHO),¹³ the Swedish public health agency and Swedish government^14,15 highlights the importance of PA for enhancing health. Further, the Swedish school law¹⁶ and curriculum¹⁷, emphasizes a health promoting school system where preschools and schools are assigned to e.g., provide children with opportunities for daily movement as well as conditions for developing movement capabilities, enjoyment of movement and an interest to be physically active. The early childhood years, often defined as 0-5 years, is regarded as a central period for PA-promotion since being a period that is fundamental for the development of PA-behaviors, overall well-being and health^{18,19,20,21,22} as well being a period where young children can develop PA-behaviors that might track into adulthood^23,24,25. For many Nordic children, much of their early childhood is spent in preschool, and in Sweden and Norway attendance is high, reaching >94% of 3-5 year-olds^26,27 hence, it is important to investigate how to create an ECE-environment that produces enriched opportunities for movement, play, exploration and thus adequate PA. Already in 1996, Siedentop²⁸ argued that effective PA-promotion must include a relationship between school, community, and family and that the school setting is the central point of this relationship, based on the discussion above, one could argue that today, the same goes for the preschool setting. Against this background, combined with the fact that the Swedish curriculum assigns preschools to work health promotive, the Nordic ECE is a setting well suited for PA-promotion, since it is a context encompassing most Nordic children at an age critical for their overall development and health.  

METHODS:The overall aim for this doctoral thesis is to, 1) develop an environment rating scale (ERS) that aligns with the theories of Ecological dynamics (ED), Enriched environment (EE) as well as the constructs of movement, play and exploration in ECE and, 2) evaluate this ERS against outcome effects such as PA, physical fitness, sleep and cognitive tasks from a large-scale intervention in ECE. 

To achieve this, four papers will be produced.I) a literature review on the topic of ERS in general, and on ERS in ECE specificallyII) method development of a new ERS that aligns with EE, ED, movement, play and explorationIII & IV) cross-sectional association studies investigating the associations of the newly developed ERS and outcome effects (e.g., PA and cognitive tasks) of pedagogical interventions in ECE, and  

RESULTS:Tentatively, the result of this dissertation is expected to provide, 

1. an ERS-tool that is able to capture how ECE environments affords, and create opportunities for movement, play and exploration in preschool children and consequently increases PA in this group. 
2. a practical ERS-tool that practitioners within ECE can use to evaluate their own environment and how it relates to creating opportunities for children’s PA via movement, play and exploration.
3. an overview of existing ERS-tools and their characteristics, e.g., validity, reliability, context, advantages and limitations. 
4. associations between the developed ERS-tool and outcome measures on child level such as total amount of PA, physical fitness, cognitive tasks and sleep. 
5. indications of effectiveness of the ERS-tool to promote PA and child development in ECE.
6. guidance for future research connected to PA-promotion, and child development in ECE. 

CONCLUSION:With individual, and public health advancements in mind, there is ample reason to enhance our understanding in the field. It is my hope that this dissertation will contribute to an ECE that advances children’s enjoyment of, and relation to, movement, learning and PA, both in an immediate and life-long perspective. 

INTRODUCTION:There are substantial evidence for the numerous positive health benefits of physical activity (PA) [1]. At the same time, PA-levels in European and Swedish children are insufficient [2]. Inadequate PA-levels, and associated noncommunicable diseases, are regarded as one of the most significant public health challenges confronting us. Hence, it is important to understand how we can promote ways for children to reach adequate PA-levels. Physical Literacy (PL), a theory with potential benefits for PA-behaviors and health, has garnered increasing attention over the last few years. Encompassing physical, affective, and cognitive dimensions PL is often described as an individual’s capacity, confidence, and motivation to partake- and engage in PA [3]. The early childhood years are suggested for PL promotion since this period is regarded as crucial for PA-behaviors, future health, and the opportunity to reach most children via school settings. However, the assessment and status of PL in young children, specifically in Sweden, is at best scarce. Consequently, research is required to assess PL and its connection to PA-levels in young Swedish children.

METHODS:The data for this study will be derived from hip-worn accelerometers (GT3X+, Actigraph) worn for 7 days to assess PA-levels, as well as a modified version of the Canadian Preschool Physical Literacy Assessment to assess PL. The study will include 412 preschool children, aged 3-6, from 20 preschools. The data will be analyzed and presented via descriptive statistics, and multi-level linear regression models will be used to determine associations between total- and intensity stratified PA-levels and PL.

RESULTS:Tentatively, the results of this study are expected to provide: 1) a picture of PL and PA in Swedish preschool children and the connection therein; 2) much-needed data for the fields of PL and early childhood research; 3) Indications on effectiveness of PL for promoting PA; and 4) guidance for future research in PL.

CONCLUSION:With individual, and public health advancements in mind, there is ample reason to enhance our understanding of the relationship between PL and PA-levels of Swedish preschool children, as well as, adding data to the PL-field. The present study has the potential to contribute to these objectives.

References:1. Warburton, D. E., & Bredin, S. S. (2017). Health benefits of physical activity: a systematic review of current systematic reviews. Current opinion in cardiology, 32(5), 541-556.2. Steene-Johannessen J, Hansen BH, Dalene KE, Kolle E, Northstone K, Møller NC, et al. Variations in accelerometry measured physical activity and sedentary time across Europe – harmonized analyses of 47,497 children and adolescents. Int J Behav Nutr Phys Act. 2020;17(1):38.3. Edwards, L. C., Bryant, A. S., Keegan, R. J., Morgan, K., & Jones, A. M. (2017). Definitions, foundations and associations of physical literacy: a systematic review. Sports medicine, 47(1), 113-126.

Introduction

It is well known that muscle strength increases in both the untrained and trained limb after a period of unilateral strength training. However, it is not known how this so called cross-education effect (CE-effect) is affected by a long period of detraining, and if there are any sex differences. Also, there are conflicting results regarding the effect of unilateral training on muscle mass in the untrained limb.

Aim

The primary objective was to study the CE-effect in men and women after a period of unilateral strength training and detraining. The secondary objective was to study if training one limb would affect the muscle mass of the homologous opposite limb.

Method

Sixteen untrained individuals, 9 females and 7 males, completed the study. The training intervention was 10 weeks (34 sessions) of unilateral strength training (leg press (LP) and leg extension (LE) exercise). 1RM and muscle thickness (vastus lateralis) were measured pre-, post- and 20 weeks post-training.

Results

Strength (1RM) in the trained leg increased for both men and woman (LP: ~60%, LE ~20%, p<0.01), with no sex differences. However, only the men had a strength increase in the untrained leg (LP: 26%, LE: 10%, p<0.05) and the non-significant increase observed for the woman (LP: 10%, LE: 3%) was significantly smaller than the increase in the men (p<0.05). Muscle thickness increased similarly for both men and women (trained leg: ~14%, p<0.01; untrained leg: ~4%, p<0.05). The detraining period did not affect strength, but muscle thickness was reduced close to pre-training values in both men and women.

Conclusion

The results of the present study show that the CE-effect is larger in men than women, and that it is long lasting (at least 20 weeks). Further, strength training of one leg can increase the muscle mass of the homologous opposite leg.