ECSS Paris 2023: OP-AP19
INTRODUCTION: Previous research has shown that swimmers sleep less prior to early morning training compared to a rest day (Sargent et al., 2014). Whether sleep can be extended by postponing the early morning training has not been investigated thus far. Moreover, it is unclear which effect this might have on performance and perceived fatigue. Therefore, the aim of the current study was to assess the effect of postponed morning training on sleep, performance and perceived fatigue in swimmers. METHODS: Employing a randomized cross-over design, this study involved twenty-seven national level youth swimmers (13F, 14M; age: 16 ± 1 y) participating in two 8-day training camps. For the duration of the camp, training commenced at 7 a.m. (early training: ET) or at 9 a.m. (late training: LT). Sleep was measured daily using the ActiGraph wGT3X-BT (ActiGraph LLC, Pensacola, FL, USA) alongside a sleep diary. Perceived fatigue was recorded daily using the Short Recovery and Stress Scale for Sport. Performance assessments, comprising 100 m and 800 m all-out tests, were conducted at the start (Pre) and end (Post) of each training camp. The effect of postponed early morning training on sleep duration and perceived fatigue was analyzed using multilevel linear modeling, while performance outcomes were assessed using a two-way analysis of variance (ANOVA). RESULTS: Sleep duration was significantly greater in ET compared to LT. (ET: 6.9 ± 0.7 h vs. LT: 7.9 ± 0.7 h; mean difference (md): 1.0 ± 1.7 h; P < 0.001; ƞ2p = 0.27). No significant intervention x training camp interaction effect was observed for 100 m performance (F(1,20) = 0.72; P = 0.41; ƞ2p < 0.01) or 800 m performance (F-(1,20) = 0.02; P = 0.88; ƞ2p < 0.01). However, perceived stress was significantly lower (ET: 3.4 ± 1.0; LT: 2.5 ± 0.9; med: -0.9 ± 2.5; P < 0.001; ƞ2p = 0.13) and perceived recovery significantly higher (ET: 2.7 ± 0.8; LT: 2.9 ± 0.7 ; md: 0.2 ± 2.0; P = 0.027; ƞ2p = 0.01) in LT compared to ET. CONCLUSION: Postponing early morning training by 2 hrs is associated with extended total sleep time and improved perceived fatigue, but does not have an acute effect on performance. However, it could be speculated that extending sleep might be important in the long-term, considering the importance of perceived fatigue and sleep loss in the development of functional overreaching (Hausswirth et al., 2014). References: Hausswirth, C., Louis, J., Aubry, A., Bonnet, G., Duffield, R., & Le Meur, Y. (2014). Evidence of Disturbed Sleep and Increased Illness in Overreached Endurance Athletes. Medicine & Science in Sports & Exercise, 46(5), 1036-1045. https://doi.org/10.1249/mss.0000000000000177 Sargent, C., Halson, S., & Roach, G. D. (2014). Sleep or swim? Early-morning training severely restricts the amount of sleep obtained by elite swimmers. European Journal of Sport Science, 14(sup1), S310-S315. https://doi.org/10.1080/17461391.2012.696711
Read CV Maxime BrandtsECSS Paris 2023: OP-AP19
INTRODUCTION: This study investigates the influence of strength training and conditioning on specialized swimming techniques, focusing on Haiyang Qin, an elite Chinese male breaststroke swimmer. Spanning from 2022 to 2023, a critical period in Haiyangs career, it examines the interplay between his physical training, rhythmic training, and physiological adaptations. The aim was to elucidate how these factors synergistically contributed to his success in winning gold medals in the 50m, 100m, and 200m breaststroke events, thereby offering valuable insights into competitive swimming training. METHODS: The study employed the following methods: (1) Training session analysis: A comprehensive examination of both aquatic and land-based training regimens, including specific swimming training and perceived exertion ratings (RPE) reported by coaches and athletes, along with monitoring of blood biochemical markers. (2) Functional testing and morphological changes: Regular assessments were carried out to evaluate morphological indicators and physical capabilities such as power and strength (Vertical Jump and Pull-up Test), speed (30 Metre Sprint Test), coordination (Y-Balance Test) and endurance (3 km Run Test). (3) Competition technical analysis: A systematic comparison was made of Haiyang Qins technical performance at the Fukuoka Championships with his previous results, with a focus on biomechanical changes and performance enhancements. RESULTS: (1) High-intensity land-based training sessions (RPE: 8.4±0.9) exhibited a significant correlation with physiological markers such as testosterone levels. Additionally, significant changes in morphology were observed, particularly in chest circumference (101cm to 107cm) and weight (84kg to 93kg). (2) Increases in strength, core stability, agility, and power output led to significant improvements in Vertical Jump and Y-Balance Tests. (3) Specific-swimming performance showed significant enhancements, including a 7.1% increase in stroke rate in the 100m event and a 3.8% increase in stroke length in the 200m event during the Fukuoka Championships. CONCLUSION: The findings indicate that a multi-approach strength training and conditioning program enhances the athletic physique, lower limb strength, and coordination. These improvements played a vital role in Haiyang Qins technical adjustments, resulting in his outstanding performance at the Fukuoka World Championships. The study highlights the potential benefits of a multi-approach physical training program for swimmers, providing valuable insights for coaches and athletes.
Read CV Yang ShuECSS Paris 2023: OP-AP19
INTRODUCTION: Turn time (TT) plays a crucial role in competitive swimming performance. Its proportion in freestyle races spanning from 100 m to 1500 m ranges between 19.69% and 36.87% [1]. The longer the distance is, the more important TT. Of which, 400 m freestyle requires athletes to have both speed and endurance, and a large number of turns can be analysed. Rotation is the main phase of the turn in swimming. It involves entire body movement around the transverse and longitudinal axes [2]. This necessitates engagement of the trunk muscles to facilitate swift and smooth rotations. Therefore, this study aimed to investigate the correlation between trunk strength and TT in 400 m freestyle among swimming athletes. METHODS: Thirteen regional swimming athletes (8 males: 18.63 y, 185.75 cm, 75.88 kg and 5 females: 16.6 y, 169.2 cm, 55.7 kg), whose average best records were 91.71% (male) and 86.86% (female) of the world records respectively, participated in the 400 m freestyle test. Data include total TT, single 15 m-turn (5 m-in: the time from 5 m to wall contact; plus 10 m-out: the time of 10 m after wall contact) in 7 turns for each participant. Trunk strength was assessed during flexion and extension using an isokinetic dynamometer (IsoMed-2000) at speeds of 60°/s and 180°/s, and bilateral trunk rotation was measured at speeds of 90°/s and 150°/s. Pearson correlations were computed between TT parameters and trunk isokinetic peak torque (PT). RESULTS: Pearson correlation showed significant negative correlations between total TT and trunk flexion (r = -0.61, P = 0.027) and extension (r = -0.575, P = 0.04) PT at 60°/s respectively. Similarly, strong to very strong correlations were observed for trunk rotation at 90°/s and 150°/s (left: r = -0.737 ~ -0.77, P = 0.002 ~ 0.004; right: r = -0.659 ~ -0.686, P = 0.01 ~ 0.014). Besides, the correlations from the first turn to the last turn gradually increased every single 15 m-turn, significantly in flexion 60°/s (from r = -0.56 to -0.639), left rotation 90°/s and 150°/s (from r = -0.646 to -0.8), and right rotation 90°/s and 150°/s (from r = -0.547 to -0.782). The higher correlation of left than right side may be caused by the habit of each participant’s rotation. After splitting the TT to 5 m-in and 10 m-out, the total 5 m-in time was negatively correlated with bilateral rotation in both 90°/s and 150°/s (r = -0.56 ~ -0.644, P = 0.018 ~ 0.046). However, the total 10 m-out time was correlated with flexion (60°/s and 180°/s), extension (60°/s), and bilateral rotation in both 90°/s and 150°/s (r = -0.601 ~ -0.806, P = 0.003 ~ 0.001). CONCLUSION: The findings suggest that (1) trunk flexion, extension, and bilateral rotation strength are strongly correlated with TT; (2) the higher correlation of left than right may be caused by habitual turning direction; (3) this correlation may strengthen as the distance increases; (4) the correlations were higher in 10 m-out phases than 5 m-in phases. REFERENCE: [1] Polach et al. 2021. [2] Puel et al. 2023.
Read CV Jiaoyang ZhongECSS Paris 2023: OP-AP19