The objective of this study was to evaluate the impact of a three-year swimming training program on selected anthropometric variables in a general population sample of pre-adolescent girls. Material and Method: The analysis included two groups of 10-year-old girls at the start of the study. Each research group consisted of 14 swimmers (body mass: 34.99 ± 2.77 kg; height: 146.00 ± 3.05 cm). The control group comprised girls (body mass: 37.93 ± 6.02 kg; height: 145.55 ± 3.88 cm) who participated only in mandatory physical education classes. The study spanned three consecutive years with measurements taken every six months. Selected anthropometric measurements were recorded. Results: Significant differences between the first and last measurements were observed for all anthropometric traits within both groups, with larger dimensions recorded at time 6. Besides height and body weight, the greatest difference was in shoulder width, with mean increases of 11.64 cm in the experimental group and 13.71 cm in the control group. No significant differences were found between the groups for most anthropometric measurements, except for body weight, where the control group gained an estimated 3.57 kg more than the swimmers over 6 years. Discussion: In conclusion, the study highlights that regular swimming training in young girls contributes to overall physical fitness and may positively influence certain body dimensions, such as chest width and foot width. However, the majority of growth in anthropometric traits appears to be driven by natural developmental processes rather than the effects of swimming training alone.

The data regarding somatic and physiological effects of sport-related physical activities in youth are limited. Moreover, whether exercise training is capable of increasing cardio-respiratory fitness remains a disputable issue. The study undertook to assess the effect of swimming training on cardio-respiratory fitness (CRF) and the development of physical traits in prepubertal boys, and to determine which of the traits is the best predictor of their CRF. Forty 10-year old prepubertal boys (10.5 ± 0.3 y) were divided into two groups (swimmers (SG), n = 20, and controls (CG), n = 20), which underwent anthropometric measurements and performed a 20 m shuttle run test (20 mSRT) semi-annually over a 3-year period. CRF indices (the number of 20 mSRT shuttles, maximal speed, and VO₂max) were higher overall in the SG compared with the CG (p < 0.001). The values of the main physique variables increased faster in the CG, but the groups showed no differentiation of physical traits. In both groups, CRF indices were associated with the participants’ physical traits, the most strongly with the sum of four skinfold thicknesses in the SG and knee breadth in the CG. These results suggest that swimming training is a form of additional physical activity that improves prepubertal boys’ CRF but does not significantly affect their physical development. In using the 20 mSRT to assess the CRF of prepubertal boys, their physical activity level and age-related changes in body fatness need to be considered.

Introduction: The aim of this research is to evaluate the somatic changes of female prepubertal swimming athletes. The question posed was: how does three years of swimming training affect the weight, body height and BMI and biological age of pre-adolescent girls who entered swimming training without pre-selection. Material and methods: The study group consisted of 14 girls aged 10 years at the start of the study (body weight: 34.99 ± 2.77 kg; body height: 146.00 ±3.05 cm) practising swimming, the control group of 14 girls aged 10 years at the start of the study (body weight: 37.93 ± 6.02 kg; body height: 145.55 ± 3.88 cm) attending physical education classes only. The study was conducted before 3 consecutive years, equally every 6 months between 8 and 12 am. Body weight and height were measured in both groups and the biological maturity shift index and body mass index were determined. Results: The analysis shows that female swimmers after systematic training have a lower body weight (F=10.78, p<0.01) and a lower BMI of 2.63 (F=12.23, p0.05). Conclusion: The study shows that swimming training influences changes in selected somatic indices of prepubertal girls. However, the conducted training does not affect the biological age, so it does not interfere with the natural development of the subjects. This may indicate a better assessment of the overall health of young female swimmers.

Objectives: The aim of this study was to indicate which variables are the most important determinants of swimming results in the 50 m front crawl among non-elite pre-pubertal female swimmers. Methods: The study group consisted of 14 female swimmers (at the time of the research commencement—biological age: 10.52 ± 0.37 years; body mass: 34.99 ± 2.77 kg; height: 146.00 ± 3.05 cm). The study was conducted over three years. The swimmers performed capacity training recommended by the British Swimming Federation. Every 6 months, in the participants the following parameters were measured: percentage of body fat; anthropometric measurements; aerobic and anaerobic capacity; and respiratory parameters: vital capacity—VC, forced expiratory volume—FEV1, and forced vital capacity—FVC. Additionally, a 50 m front crawl swim test was performed. Results: After adjusting for multicollinearity, the most influential determinants of swimming performance were anthropometric measures: shoulder width was the most influential predictor, with a regression coefficient of −0.66, followed by foot length (with a beta of −0.15) and chest depth (with a beta of 0.008). The remaining anthropometric and physical predictors did not contribute to the prediction of 50 m freestyle performance. Conclusions: These research results suggest to coaches and trainers that sports performance in sprint distances in pre-pubertal girls is not determined by aerobic and anaerobic capacity or body fat but is based on the somatic build of the swimmer.

Introduction: The aim of this study was to assess the impact of a 3-year swimming training programme on body fat measurements in adolescent girls, without prior selection. Method: Two groups of 10-year-old girls were analysed at the beginning of the study (4th grade in primary school). The experimental group consisted of 14 swimmers (body mass: 34.99 ± 2.77 kg; height: 146.00 ± 3.05 cm). The control group consisted of 14 girls (body mass: 37.93 ± 6.02 kg; height: 145.55 ± 3.88 cm) who only participated in mandatory physical education classes. The study was conducted over a period of 3 years, with measurements taken every 6 months. Body fat was measured through the thickness of skinfolds at four anatomical locations: above the biceps; above the triceps; below the lower angle of the scapula; and above the superior iliac crest. Based on these measurements, the percentage of body fat was calculated. Results: Statistical analysis revealed that despite the lack of initial selection, there was no significant difference in the percentage of body fat between the experimental and control groups at the start of the study—18.62% vs 24.85%. This difference persisted until the final measurement after 3 years, at which point it became statistically significant—17.31% vs 27.14% (F = 37.44, p < 0.05). Discussion: Our findings indicate that 3 years of swimming training in adolescent girls resulted in a reduction in fat tissue growth across all four measurement sites. Initially, body fat percentage had a strong negative impact on VO₂ max, particularly in the experimental group. However, this effect diminished in both groups over the course of the study. Conclusion: Swimming may be an effective means of preventing obesity. Coaches should consider a slim physique in swimming candidates.

Aims: The aim of the study was to identify which anthropometric, physiological, and respiratory parameters are the most important determinants of 400 m front crawl swimming performance among prepubescent, non-elite female swimmers. Materials and methods: The study group consisted of 14 swimmers (mean biological age at baseline: 10.52 ± 0.37 years; body mass: 34.99 ± 2.77 kg; height: 146.00 ± 3.05 cm). The study was conducted over three years. The swimmers followed endurance training recommended by the British Swimming Federation. Every six months, the following parameters were measured: percentage of body fat, anthropometric variables, aerobic and anaerobic capacity, respiratory parameters [vital capacity [VC], forced expiratory volume in 1 s [FEV ₁ ], forced vital capacity [FVC]], and a 400 m front crawl swimming test. Results: After accounting for multicollinearity, the most influential factors determining 400 m front crawl performance were foot dimensions, VC and % body fat. Other somatic and physiological predictors had a less of an impact on swimming performance. Conclusions: The 400 m front crawl performance among prepubescent girls is not determined by aerobic capacity but rather by foot length and respiratory indicators.