Effect of Physical Activity Behaviors, Team Sports, and Sitting Time on Body Image and Exercise Dependence

Background and Purpose: Mental health is a fundamental component of overall well-being, closely linked to quality of life and influenced by lifestyle factors such as smoking, diet, alcohol consumption, and high sitting time behavior. Physical activity, exercise, and sport participation are widely recognized as protective determinants, reducing anxiety and depression while enhancing self-confidence, self-efficacy, and body image. Body image is a multidimensional construct that includes perceptual, cognitive–affective, and behavioral dimensions. The effect of exercise or sport on body image may be due the improvements in physical fitness and body composition; however, athletes may also experience body dissatisfaction due to aesthetic ideals, weight categories, or performance-related pressures. This paradox reflects sport-specific demands that can develop maladaptive behavior such as unhealthy diet, worst chronotype or exercise dependence. Moreover, sex differences play a key role on body image, where women are often more dissatisfied with their bodies. Beyond body image, other lifestyle factors, particularly dietary adherence and sleep quality, are key determinants of both health and performance. Adherence to the Mediterranean diet, characterized by fresh and minimally processed foods, supports metabolic and cardiovascular health, enhances sleep quality, and reduces the risk of chronic diseases and psychological disorders. Sleep quality is essential for physical recovery, increase performance, and mental health, but athletes frequently could develop poor sleep quality given the higher training demands and competitive stress. The interaction among body image, diet, and sleep highlights the need for a multidimensional perspective when examining the health and well-being of athletes and physically active populations. In Italy, soccer and volleyball are the most practiced team sports among young adults, providing a relevant context to study these dynamics, particularly given the sociocultural pressures. Given the complex link between physical activity, perception of one’s own body, excessive exercise, healthy diet, and sleep quality, there is a need for an in-depth investigation that examines these dynamics in populations with different physical activity behaviors. Therefore, this doctoral research aims to investigate, through a multidimensional approach, how lifestyle behaviors, including team sport participation, physical activity levels, and high sitting time behavior, relate to body image, exercise dependence, dietary adherence, and sleep quality, also considering sex differences. Methods: Three cross-sectional studies were conducted in the Human Performance Lab of the University of Cassino and Lazio Meridionale, in accordance with the Declaration of Helsinki and IRB approval (8 March 2023; approval number: 9407). Young adults (18-35 years) were recruited among the student and student athlete population of the University of Cassino and Lazio Meridionale, testing individually during afternoon sessions (around 30 min). Student-athletes who reported regular team sport participation were included if they had ≥ 4 years of training in the sex-typical Italian team sport (males: soccer; females: volleyball) and competed at the Tier-2 amateur level. Non-athletes were classified into (i) physically active individuals (males and females) if they recognized as health-enhancing physical activity by the International Physical Activity Questionnaire or (ii) individuals with high sitting time behavior (males and females) if reported sitting time 5 or more hours in total each day. Body image and exercise dependence were assessed with the Italian Body Image Dimensional Assessment (BIDA) and 21-item Exercise Dependence Scale (EDS-21). BIDA is a silhouette-based scale, where three direct indices are derived from the participants’ responses: body dissatisfaction, sexual body dissatisfaction, and comparative body dissatisfaction. EDS-21 is a six-point Likert scale that evaluates seven dimensions of exercise dependence (tolerance, withdrawal, intention effects, lack of control, time, reductions in other activities, and continuance) and provides an overall score. The dietary adherence was assessed using the Italian version of the 14-item questionnaire for the assessment of PREvención con DIetaMEDiterránea (PREDIMED). Scores of 1 and 0 were assigned for each item; the PREDIMED score was calculated as follows: 0–5, lowest adherence; score 6–9, average adherence; score ≥10, highest adherence. Regarding sleep quality and chronotype, the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the Morningness–Eveningness Questionnaire (MEQ) were used. PSQI consists of seven components, including subjective sleep quality, habitual sleep efficiency, sleep medication use, sleep duration, sleep latency, sleep disturbances, and daytime dysfunction. The PSQI score is a global score ranging from zero to 21, and poor sleep quality was defined as a PSQI score of 5 or greater, while good sleep quality was defined as a PSQI score of less than 5. The MEQ consists of 19 questions regarding sleep habits and daily performance. The sum of the individual items produced a total score ranging from 16 to 86, and based on their score, individuals were classified as morning (59–86), neither (42–58), or evening (16–41) chronotypes. The statistical analysis from this project includes the following: Phase I: A multivariate analysis of variance (MANOVA) was used to examine the effects of different levels of physical activity, team sport participation (soccer and volleyball), and high sitting time behavior on participants’ body image indices and dimensions of exercise dependence according to sex. Phase II: One-way analysis of variance (ANOVA) examined differences between student-athletes and non-athlete students with high sitting times on PREDIMED, PSQI score, the seven component scores of sleep, MEQ, and BIDA scores. Phase III: One-way ANOVA was used to compare PSQI score, PREDIMED score, and MEQ score among soccer players, physically active individuals, and individuals with high sitting time behavior. Pearson’s correlation coefficients (r) were calculated to examine the associations between PSQI score, PREDIMED score, and MEQ score. Results: The main findings from this project include the following: Phase I: Volleyball players showed significantly higher body dissatisfaction than soccer players and the male physically active group, who had lower values than the female high sitting time behavior group. Soccer players had lower comparative body dissatisfaction values than volleyball players, and females with high sitting time behavior, who had higher values than males with high sitting time behavior. Females with high sitting time behavior had significantly lower exercise dependence scale score than volleyball players, soccer players, and physically active males. Phase II: Student-athletes showed significantly higher adherence to the Mediterranean diet, although experiencing poorer sleep quality compared to non-athlete students with high sitting time. Conversely, comparative body dissatisfaction was significantly higher in non-athlete students with high sitting time than in student-athletes. Phase III: Better sleep quality was found in amateur soccer players and physically active individuals than in individuals with high sitting time behavior. No significant differences were found in adherence to the Mediterranean diet and chronotype. A negative relationship was observed between chronotype and sleep quality among individuals with high sitting time. Conclusions: The findings highlight the impact of regular physical activity on body dissatisfaction and the variance in body image perceptions between the sexes. The high exercise dependence values found in volleyball and soccer players and physically active males suggest an effect of intense training and maladaptive exercise behaviors, underlining the need for comprehensive strategies to address exercise dependence. Moreover, the findings highlighted a paradoxical health pattern in female student-athletes who combine healthier eating habits with poorer sleep quality. Structured behavioral routines in amateur soccer may support a good sleep quality, although adherence to the Mediterranean diet appears independent of amateur sport participation. These findings suggest that participation in sports alone may not be sufficient to promote healthier dietary habits or protect against body image concerns. Multidimensional strategies that integrate physical activity, nutritional education, and body image awareness are needed to improve health-related behaviors and psychological well-being in university and athlete-students.