Associations between Selected Biological Features and Absolute and Relative Swimming Performance of Prepubescent Boys over a 3‐Year Swimming Training Program: A Longitudinal Study

Abstract

The study aimed to investigate the effect of 3-year swimming training on selected biological variables in prepubescent male swimmers and to determine the best predictors of absolute (VSa) and relative (VSr) swimming velocity for 50 m and 400 m front crawl. Twenty-one 10-year old boys subjected to endurance swimming training (4 x 70 min per week) and 18 boys consisting a control group were assessed semi-annually for basic anthropometric and respiratory characteristics, breath-hold time (BHT), VO2max, leg explosiveness (HJ), and abdominal strength endurance (ASE). After three years of training, BHT (p < 0.001), VO2max (p < 0.01), HJ (p < 0.01) and ASE (p < 0.01) were greater in the swimmers than in the controls. VSa and VSr expressed as a percentage of baseline velocity increased more for the 50 m than for the 400 m distance (p < 0.001 and p < 0.01, respectively). The 50 m VSa and VSr positively correlated with those obtained for the distance of 400 m (in both cases p < 0.001). Baseline VSa was negatively correlated with the increase in absolute swimming velocity for both distances (50 m: r = -0.684, p < 0.001 and 400 m: r = -0.673, p < 0.001). The best predictors of VSa for 50 m and 400 m front crawl were HJ (r2 = 0.388; p < 0.001) and VO2max (r2 = 0.333; p < 0.001), respectively. The key predictors of VSr for both distances were age (50 m: r2 = 0.340, p < 0.001 and 400 m: r2 = 0.207, p < 0.001) and, after excluding it from analysis, HJ (50 m: r2 = 0.176, p < 0.001 and 400 m: r2 = 0.104, p < 0.001). These results suggest that regardless of prepubescent boys’ initial abilities and exercise capacity, improvement in their swimming performance mainly depends on increases in power and neuromuscular coordination.

Understanding the Importance of Drag Coefficient Assessment for a Deeper Insight into the Hydrodynamic Profile of Swimmers

“…Thus, the C D (that changes according to the shape, orientation, and Reynolds number) will be the variable responsible for such improvement. Considering young swimmers, they tend to meaningfully increase their swimming speed due to growth and technical development ( Kuberski et al, 2022 ; Morais et al, 2013 ). However, drag also increases with speed.…”