CHANGES IN THE LEVEL OF FITNESS AND PHYSICAL DEVELOPMENT IN CHILDREN FROM FIRST-GRADE SWIMMING CLASSES COMPARED TO PEERS
Authors: Żukowska Hanna , Szark-Eckardt Mirosława 
Published: April 2021

Introduction. In the changes occurring in competitive sport, proper choice and selection for sport and the age of starting the training are of great importance.

Aim. Determining the magnitude of changes in physical fitness and physical development of first-grade children practicing swimming in relation to the non-training peers.

Material and methods.
The study included two groups of children - the first one was a children practicing swimming (26 boys and 23 girls) and the second one was a non-training class (26 boys and 23 girls). In both groups, MTSF trials were conducted in September and June. The results of the study focused on three aspects: the evaluation of sexual dimorphism, the identification of differences and their direction between groups and sex.
Results.
There were no statistically significant differences in physical development among children who practiced swimming. There were statistically significant differences in body heights in the non-training group - only in the first study (boys – 120.30; girls – 117.86) also in body weight in the first study (boys – 24.57; girls – 21.22) and also in the second study (boys – 26,80; girls – 22,83). In the assessment of physical fitness, in the group of children training swimming, sexual dimorphism was found in: standing long jump (only in the first study boys – 151,65, girls – 134,96); hand strength measurement (only in the first study boys – 23.5; girls – 19,36); bent arm hang, both in the first study (boys – 13,40; girls – 7,70) and also in the second study (ch-14,46; dz-6,31); forward stretches (only in the first study boys – 5; girls – 1.34); 4x10m run both in the first study (boys – 14,54; girls – 15,23) and also in the second study (boys – 13,66; girls – 15,11). Whereas, in the control group in: standing long jump (also only in the first study boys – 107.78; hand strength measurement in both the first study (boys – 18,95; girls – 12,26) as in the second study (boys – 12,09; girls – 12,77); bent arm hang (only in the first study (boys – 8.21; girls – 3.02); forward stretches in both the first (boys – 2,43; girls – 1,30) as in the second study (boys – 3,30; girls – 2,19).
Conclusions.
In both groups, boys as well as girls reported statistically significant changes in physical development, which is a normal symptom of growth, but only in the group of girls a statistically significant increase in BMI occured. In evaluating swimming training and its effect on fitness, it can be stated that the boys were positively influenced by such tests as (bent arm hang and sit-ups) and negatively by 50 m and 600 m run. On the other hand, among girls: positive only in the sit-ups test, and negative, as in the group of boys in at 50 m and 600 m run. In the group of girls, it was also noted that the trainees, despite the fact that in the first study achieved a significantly better result in the bent arm hang test, in the second attempt they obtained a considerably weaker result, while the non-training girls in the second measurement achieved a statistically better result than the first one.