ECSS Paris 2023: OP-AP17
INTRODUCTION: Front crawl is the fastest and most streamlined swimming stroke, with the swimming phase accounting for the majority of race time, excluding the start and turns [1]. Effectively utilizing aquatic resistance training to simulate race conditions and enhance swimming performance is crucial. Therefore, the purpose of this study is to compare the effects of different aquatic resistance loads on swimming performance and determine the optimal resistance load. The findings aim to provide practical guidance for implementing aquatic resistance training. METHODS: This study recruited 19 male elite swimmers. Resistance cord was attached to the waist using a semi-systematic electromechanical device (1080 Sprint 2). Resistance loads were set at 1%, 3%, and 5% of body weight for a 25 m front crawl sprint test. Analyze parameters such as maximum velocity, peak force, peak power, and velocity decrement rate (VDR) from 5 to 20 m. One-way repeated measures ANOVA was conducted to examine the effects of different resistance loads on short-distance sprint performance. RESULTS: The results of this study showed that under different resistance loads. The 1% load achieved the highest maximum velocity, while maximum velocity decreased as resistance load increased (p = .000). In addition, The peak force and peak power were highest at the 5% load (p = .00). Further analysis of the VDR1-5% revealed an 18% reduction (p = .000), 10% reduction from VDR1-3% (p = .00), and 8% reduction from VDR3-5% (p = .000). CONCLUSION: The results of this study indicate that an increase in resistance load further enhances peak force and peak power, demonstrating that a moderate increase in resistance can effectively improve an athlete’s strength and power output. However, excessive resistance may lead to a significant decline in maximum velocity, which is detrimental to explosive power development. Given that the VDR1-5% was significantly higher than at VDR1-3%, 5% body weight resistance load is not conducive to maximum velocity. Therefore, 3% resistance load is recommended as an optimal training intensity to help athletes achieve better strength and speed performance for developing more tailored resistance training strategies for athletes at different competitive levels. 1. Arellano et al. (2018)
Read CV Zi-Wei ZhouECSS Paris 2023: OP-AP17
INTRODUCTION: Trunk muscles are critical for effective freestyle turn performance because they facilitate dual rotational movements—rolling and twisting. Enhanced trunk strength not only stabilizes the spine and overall body but also improves underwater performance (e.g., gliding and undulatory underwater swimming) by reducing disturbances and drag while increasing body amplitude [1-2]. Previous studies have shown that incorporating trunk strength training (TST) into day-land programs can improve 50 m freestyle performance and turn efficiency (measured as the 5 m segment following wall contact) [3-4]. However, due to differences in performance parameters between sprint- and middle-distance events, the effects of TST on 400 m freestyle remain unclear. Thus, thus study aimed to examine the impact of TST on turn time performance during 400 m freestyle among national-level swimmers. METHODS: Fourteen national-level swimmers (8 males, 6 females) specializing in middle-distance freestyle were divided into an experimental group (EG: 18.3 ± 3.3 y, 177.3 ± 9.5 cm, 65.7 ± 9.5 kg) and a control group (CG: 20.3 ± 4.2 y, 179.5 ± 7.3 cm, 69.4 ± 11.7 kg). In addition to their regular day-land training (focusing on upper and lower limb strength), the EG completed an 8 weeks TST program (three sessions per week) divided into two phases: a basic stage (4 weeks) focusing on trunk bilateral rotation stability and dynamic strength, followed by advanced stage (4 weeks) emphasizing explosive power and specific turn exercise. Pre- and post-intervention assessments included trunk isokinetic peak force (PT) using an IsoMed 2000 dynamometer for flexion-extension (60°/s) bilateral rotation (150°/s), and turn time parameters during 400 m freestyle test. Turn performance was evaluated by overall turn time (OTT: the cumulative time for 7 turns, measured from the last 5 m before the rolling rotation to the 10 m mark after wall contact) and the average 5 m round turn time (5 m-RTT). A two-way repeated measures ANOVA was used to analyze intervention effects. RESULTS: Significant interactions between time (pre vs. post) and group (EG vs. CG) were found for trunk flexion PT (F = 5.600, p = 0.036, η2p = 0.318), extension PT (F = 5.534, p = 0.037, η2p = 0.316), left rotation PT (F = 19.496, p = 0.001, η2p = 0.619) and right rotation PT (F = 10.626, p = 0.007, η2p = 0.470), OTT (F = 15.061, p = 0.002, η2p = 0.557), 5 m-RTT (F = 21.396, p = 0.001, η2p = 0.641), and overall 400 m freestyle performance (F = 9.526, p = 0.009, η2p = 0.443). Compared to the CG, the EG showed significantly greater improvements in trunk strength and turn performance. CONCLUSION: Combined TST can enhance trunk flexion, extension, and bilateral rotation strength, leading to improved turn efficiency and overall performance in 400 m freestyle among national-level swimmers. Reference: [1] Kwok et al., 2021; [2] Ikeda et al., 2021; [3] Weston et al., 2015; [4] Karpiński et al., 2020
Read CV Jiaoyang ZhongECSS Paris 2023: OP-AP17
INTRODUCTION: This study focuses on Chinese elite swimmers and deeply analyzes their arm stroke force characteristics, aiming to provide crucial scientific bases for enhancing athletes athletic performance and optimizing training programs. By measuring the arm strokes of 48 high-level swimmers during a 50-meter all-out swim, comprehensively collecting and analyzing the force data of arm strokes, this research reveals the internal connections and laws among various force indicators, explores the key factors influencing swimming performance, breaks through the limitations of traditional training ideas, and lays the foundation for formulating innovative training strategies. METHODS: The eoswimbetter force plate was used to test 48 freestyle swimmers (FINA score 852 ± 8, with a training experience of 7.3 ± 3.5 years and the dominant side being the right hand). The athletes first completed a standardized routine warm-up and then swam a 50-meter freestyle with full effort while breathing normally, ensuring that the test conditions were close to the actual competition situation. Various statistical methods were applied to process the data obtained from the force plate. Descriptive statistics such as means and standard deviations were calculated, box plots and heat maps were drawn, and the correlations among various indicators were thoroughly analyzed to explore the characteristics and laws of arm stroke mechanics. RESULTS: Regarding the individual characteristics of the athletes, the average force has a mean value of 2.35, with differences among different athletes, and shows a strong positive correlation (with a correlation coefficient of 0.82) with the average forces of the left and right hands. The average stroke frequency has a mean value of 38.71 and a high degree of dispersion (standard deviation of 8.21), and has a certain positive correlation with the number of movements, being affected by factors such as personal habits. The force distribution has different values in various directions among different athletes, reflecting the differences in the emphasis of force application. The forward propulsion efficiency percentage has a mean value of 0.48, with concentrated data, and has a certain positive correlation with the number of movements, but a weak correlation with the average force and average stroke frequency. CONCLUSION: From the perspective of the group performance of the athletes, the data were classified according to quartiles, clarifying the performance level distribution of different athletes in terms of average force, stroke frequency and other indicators. Based on individual differences, personalized training strategies can be formulated. In terms of the symmetry characteristics of arm strokes, the average symmetry index is 0.18, with a standard deviation of 0.15, showing obvious individual differences. Athletes with a symmetry index close to 0 have excellent symmetry in arm stroke mechanics; those in the range of 0.1 - 0.3 have relatively good symmetry; those in the range of 0.3 -
Read CV mingyu ShangECSS Paris 2023: OP-AP17