There is increasing presentation of psychological symptoms in children and adolescent, elevating societal concerns about possible causes and consequences. One in five children worldwide experience mental health problems (Kieling et al., 2011). The most common symptoms are those of anxiety and depression. Approximately one in ten young people currently have a mood disorder in the United Kingdom (Green et al., 2004) and the United States (Merikangas et al., 2010). A systematic review by Bor et al, 2014 demonstrated that internalizing problems is increasing in adolescent girls but not so clearly in boys (Bor et al., 2014). Psychological symptoms and emotion differences is described by Rottenberg and Gross in (2003) (Rottenberg and Gross, 2003), who describe emotion as a ""storm" while psychological symptoms are more like a ""seasonal climate change". Basically emotion is a harmonized reaction to an important motivation, and causes an explicit behaviour which is short term and could disappear with losing the motivation. Unhealthy psychological symptoms form slowly and have a longer-term effects (Rottenberg and Gross, 2003).
This study used the Flanker task as a measure of cognitive control in early adolescents. There are several studies, which support that cognitive control, and psychological symptoms are interrelated with mood affecting performance during different cognitive tasks including reaction time (Peretti, 1998; Reveillon, 2018).; Reaction time (RT) is recording the time between a stimulus and response, typically including both thinking and movement time (Donders, 1868-1869). As such, RT measured by flanker task is an indicator of the inhibition of movement responses /and vulnerability to distractions. The Flanker task requires capacity of resisting distraction and "interference control" (Sanders and Lamers, 2002; Scharinger et al, 2015). These capabilities make the flanker task a suitable tool to assess cognitive control of movement in adolescents. Although there are limited studies exploring emotions and cognitive control in 9-11 year olds' (Reveillon, 2018).
Darwin was one the first researchers which in 1872 investigated the association between human emotions and movement in "The Expression of the Emotions in Man and Animals" (Darwin, 1872). More recent studies by Michalak et al. (2009) and Gross et al., (2012) showed that emotions affect movement patterns. Lemke et al., (2000) found that gait speed and stride length were 15.5 and 6.3% less, respectively, for individuals with major depressive disorder compared with control individuals (Lemke et al., 2000). Evidence suggests that children and adolescents who are more physically active, experience lower levels of psychological symptoms such as, anxiety, depression and mood difficulties, and have a higher self-esteem rather than less active children and adolescents (Ekeland et al., 2005). Moreover, in support of the direction of causality, a review of reviews about physical activity and psychological symptoms shows that conducting routine physical activity can reduce depression and improve self-esteem, cognitive performance and academic achievement in children and adolescents (Biddle and Asare, 2011). However, whether individuals with low mood move less or moving less leads to low mood has not been established.
Finally there is a strong inter-relationship between cognitive functioning and movement quality and quantity strongly evidenced in adults (Meester et al., 2014; Verlinden, 2014) which implicate the importance of the body mind axis with emerging evidence of a relationship during childhood and adolescence (review of exercise on cognition) (Biddle and Asare, 2011; Hogan et al., 2013). Again, the direction of causality is unclear and complicated by individual, family, community contextual and personal factors.
Considering the evidence to date, and underpinning understanding of these inter-relationships, we hypothesize that young people with unhealthy psychological symptoms, particularly emotional problems will react slower, move slower and subsequently perform less vigorous physical activity. In this study unhealthy psychological symptoms including emotional problems, will be evaluated alongside measures of movement quality and quantity in a whole year group of adolescents.
A Cross sectional study design used in this study to assess the reflection of psychology symptoms on selected measures of quality and quantity of movement in adolescents.
All of the participants recruited from year 9 average age of 13.36 ([+ or -] 0.48) of an urban UK school as a part of the Engagement, Participation, Inclusion and Confidence in Sport study (EPIC) with clinical trials.gov identifier (NCT number): NCT03150784. This study was part of the screening phase of the EPIC at baseline and included four different assessments including the Flanker test for reaction time; a gait test, a physical activity assessment and the Strengths and Difficulties Questionnaire (SDQ).
Ethical approval granted by Oxford Brookes University Ethical Advisory Committee (UREC 140844). Additional authorization obtained from the school's head teacher to recruit participants, and written consent collected from each participant's parent or legal guardian.
Evaluation of unhealthy psychological symptoms and emotional problems: The Strengths and Difficulties Questionnaire (SDQ) is a validated screening tool for evaluating psychological symptoms including emotional and behavioural problems in children and adolescents (Goodman, 1997; 2001). This study used the English original youth 11-17 self-report version with 25 questions, which evaluates 5 factors: Conduct Problems, Hyperactivity/inattention, Emotional symptoms, Peer relationship problems and pro-social scales (Goodman, 1997; 2001). Total psychological symptoms scores calculated using all but the prosocial scale (Goodman, 1997; 2001). In line with the recommendations, this study utilized 4 main factors (Conduct Problems, Hyperactivity/inattention, Emotional symptoms, Peer relationship problems) for calculation of psychological symptoms.
The resultant score ranges from 0 to 40. Scores divided into 4 categories ('Close to average' (0 - 14), 'slightly raised' (15 - 17), 'high' (18 - 19) and 'very high' (20 - 40)). Participants with higher scores have the higher level of psychological symptoms (Goodman, 1997; 2001).
For assessment of emotional problems, the same scoring method used based on the (not true, somewhat true and certainly true) answers for the five emotional questions in the SDQ questionnaire. The questions included; (Often complains of headaches, stomachaches or sickness, Many worries or often seems worried, Often unhappy, depressed or tearful, Nervous or clingy in new situations, easily loses confidence, Many fears, easily scared) (Figure 1). The Emotional problem scores were categorized according to 4 different levels: ('Close to average' (0 - 4), 'slightly raised' (5), high' (6) and 'very high' (7 - 10)) (Goodman, 1997; 2001).
Flanker test: The Flanker task (Eriksen and Eriksen, 1974) has been used in numerous studies, and can be broadly referred to as a cognitive control task which measures a person's capability to focus on the task and respond appropriately (Casey et al., 2005). For assessing total RT, congruent RT, incongruent RT and average RT during the test, a modified version of the Flanker test was used (Eriksen and Eriksen, 1974). On each trial, adolescents were presented an array of five blue fish pictures consisting of a central picture (target stimulus) surrounded by two pictures on each side of it (flankers). The task consists of 5 practice and 25 main trials. The test contains 4 trial types: same direction (congruent: >>>) or the opposite direction (incongruent: >>). In the current study, 52% of the tasks were congruent and 48% of tasks were incongruent. A trial starts with a blank screen for 500ms, followed by the stimulus array for 500ms and another blank screen for 1684ms. Responses within 500ms and 1500ms after stimulus onset considered valid (Eriksen and Eriksen, 1974). Researchers asked the study participants to sit in front of a laptop computer. A skilled researcher explained the instruction for them. According to this study instruction, participants had to use their both index fingers to click on left or right arrow buttons on keyboard if the fish in the middle was facing to the left or right. Data for each participant recorded in an excel spreadsheet and total RT, Average of RT, Congruent RT and Incongruent RT calculated for all the participants.
Gait: Gait assessed by administering an instrumented standardized 10-metre walk test, whereby participants were instructed to walk from standing, at their self-selected walking pace to a 10-metre line where they were instructed to stop and remain standing still for an additional 2 seconds. Participants were instrumented by an inertial measurement unit (LPMS-B2, Life Performance Research, Japan) attached over the projected centre of mass located over the 4th lumbar vertebra (Esser et al., 2009). Acceleration transformed to vertical positioning, driving an inverted pendulum model to derive both temporal (cadence [steps/min], step time [ms]) and spatial gait parameters (stride length [m], and walking speed [m/s]) (Esser et al., 2009; Esser, 2011). Walk ratio, described as the stride length to cadence ratio [mm/ (steps/min) was derived as an indicator of motor control (Lowe et al., 2019). Gait data was standardized with the participants height and feet size using a lab view program (DataGait V11.1) developed by Oxford Brookes University.
Accelerometer: This study used objective method for assessment of physical activity. Daily amount of sedentary behaviour and physical activity time measured using the Axivity AX3, a "wrist-worn" tri-axial accelerometer designed by Open Lab...