(1) Background: There are few studies investigating the relationship between physical fitness and body composition in young adults and, to our knowledge, there are no such reports focusing specifically on physiotherapy students. This observational study aimed to assess the relationship between physical fitness and selected anthropometric measurements as well as body composition in Polish students in the first year and in the final year of a university course in physiotherapy. (2) Methods: A group of 100 randomly selected individuals were recruited among first- and fifth-year students of physiotherapy (50% women), who were assigned to two groups: A (aged 19 years) and B (aged 23 years). Body composition was assessed using a Tanita TBF-300 Analyzer, and physical fitness was measured using Zuchora’s Physical Fitness Index. (3) Results: A higher level of general fitness was identified in students from Group B (p = 0.0261), and lower values of the fat mass index was found in Group A (p = 0.0441). Group A was found with correlations between general level of physical fitness and the following indexes: fat% (R = −0.4; p = 0.0018), FM (R = −0.3; p = 0.0310), FFM (R = 0.3; p = 0.0229) and TBW (R = 0.4; p = 0.0024), whereas Group B was found with correlations between general physical fitness and BMI (R = 0.3; p = 0.0308) as well as FM index (R = 0.3; p = 0.0431). (4) Conclusions: The findings show significant differences between the groups in physical fitness, body composition and selected anthropometric measurements. Older students presented higher level of general fitness, whereas younger students were found with a lower mean value of fat index.

Introduction. Physical fitness is defined as the ability to undertake motor tasks in various life situations. Its development is determined by genotype, health, and lifestyle, but also by many socio-economic and environmental factors. The aim is to determine the environmental factors affecting motor abilities and physical fitness in adolescents. Material and Methods. The authors enrolled 235 high school students aged 16-17 years to participate in this study. The study procedures included Zuchora’s Physical Fitness Index and a survey containing questions regarding general personal information and social-, family- and environment-related factors. Results. No differences occurred in motor abilities and physical fitness between adolescents according to the place and type of residence. In girls, a positive correlation appeared between the number of working people in the family with abdominal muscle strength and general physical fitness. In boys, a positive correlation occurred between arm strength and the number of family members, the number of working people in a family, and the number of children in a family. There was also a positive correlation between the number of children in a family and general physical fitness. In boys with different levels of activity in childhood, differences were found in speed, jumping ability, arm strength, and general physical fitness. In girls with different levels of physical activity in childhood, differences occurred in abdominal strength and general physical fitness. Conclusions. The number of family members, working people and children in a family, and childhood activity seem to be factors determining motor abilities and physical fitness in adolescents while living conditions such as place and type of residence and sharing the bedroom do not.