Search Results (169)

Background: Estimating race times for open-water swimming based on pool swimming times could be useful for talent identification and training optimisation. We aimed to compare the swimming speeds of the world’s top and other swimmers in the 2023 Aquatics Championship men’s 10 km OWS race. Methods: Sixty-five swimmers were divided into four groups: G1 (1st–10th positions), G2 (11st–30th positions), G3 (31st–47th positions), and G4 (48th–65th positions). Swimming speed, stroke frequency (SF), and stroke length (SL) for each lap (laps 1–6) were recorded. Critical speed (CS) was calculated from each participant’s personal best times in the 400, 800, and 1500 m freestyle events in the pool. Swimming speed against CS was calculated (%CS). Results: The top performance group (G1) maintained their swimming speed from beginning (lap 1, 1.53 m/s) to end (lap 6, 1.50 m/s), at 92.7 ± 1.9% of CS, characterised by longer SL (1.26 m) and lower SF (72.86 rpm). G3 and G4 were unable to maintain their swimming speed, which decreased from G3: 97.64 ± 1.62% and G4: 96.10 ± 1.96% of CS at lap 1 to G3: 88.39 ± 3.78% and G4: 85.13 ± 5.04% at lap 6. This reduction in swimming speed is consistent with the increased reliance on anaerobic metabolism reported in previous studies under similar conditions. Conclusions: Race pacing for maintaining speeds of 92%CS throughout the race could be an important resilient index in open-water swimming. %CS might be a useful index for estimating the athletic performance level in open-water swimming. Full article

Objective: As performance progression provides an essential indicator for talent selection and development, this study aimed to compare annual swimming performance progression between different competitive levels and to establish benchmarks for long-term athlete development. Methods: Annual best times of swimmers who competed up to the age of 21 years and achieved over 450 World Aquatics points were extracted from the database of European Aquatics. A total of 13,310 male and 7798 female pool swimmers of all race distances were grouped into three performance levels. Results: The results showed a continuous decline in annual performance progression throughout the years across all race distances (all p < 0.001) and in both sexes. There were differences between performance level across the age groups for all race distances in male swimmers, but only for the 100–400 m races in females (p < 0.05). Absolute performance showed significant main effects for level and age over all race distances for both sexes (all p < 0.001). Conclusions: Annual performance progression of swimmers consistently decreases across the competitive lifetime in both sexes, regardless of race distance and performance level. The event-specific benchmarks should be used as a framework to set realistic goals for both sexes and swimmers of different competitive levels, as well as to guide swimmers throughout their careers. Full article

Background: Optimal nutrition and training regimens are essential for athletes to maximize performance and recovery. Probiotic supplementation, through the modulation of the gut microbiota, and omega-3 fatty acids, known for their anti-inflammatory properties, may enhance physiological adaptations when combined with targeted training. This study evaluated the effects of probiotics and omega-3 supplementation, alongside ultra-short race pace training (USRPT), on performance metrics in competitive sprint swimmers. Methods: In this double-blind, placebo-controlled study, 60 male sprint swimmers (age: 19.2 ± 3.6 years; height: 182.2 ± 5.2 cm; weight: 81.6 ± 4.4 kg) with a minimum of five years of training experience, were randomly assigned to six groups (n = 10 per group): (1) Control (CON), (2) USRPT only, (3) Placebo + USRPT (PLA + USRPT), (4) Probiotics + USRPT (PRO + USRPT), (5) Omega-3 + USRPT (OMEGA + USRPT), and (6) Probiotics + Omega-3 + USRPT (PRO + OMEGA + USRPT). Over the eight-week intervention, the participants in PRO + USRPT consumed one multi-strain probiotic capsule daily (4.5 × 10¹¹ CFU) and a placebo capsule. Those in OMEGA + USRPT ingested 1000 mg of fish oil after lunch (500 mg EPA and 180 mg DHA per capsule) paired with a placebo capsule. The combined supplementation group (PRO + OMEGA + USRPT) received both probiotic and omega-3 capsules. The PLA + USRPT group consumed two starch capsules daily. The USRPT protocol was implemented across all the training groups, where the swimmers performed 17 sets of 25 m and 12.5 m sprints based on weekly recorded race times. Performance assessments included pre- and post-test measurements of sprint times (50 m and 100 m freestyle), vertical jump tests (both in water and on dry land), and other strength and endurance metrics (reaction time, agility T-test, sprint index, fatigue index, and velocity). Results: The combined intervention of probiotics and omega-3 with USRPT produced the greatest improvements in performance. The PRO + OMEGA + USRPT group reduced 50 m freestyle time by 1.92% (p = 0.002, pEta² = 0.286) and 100 m freestyle time by 2.48% (p = 0.041, pEta² = 0.229), demonstrating significant Time × Group interactions consistent with a synergistic effect. Additionally, the sprint index improved (pEta² = 0.139, p = 0.013) and reaction time decreased (pEta² = 0.241, p = 0.009) in the combined group, indicating enhanced anaerobic capacity and neuromuscular responsiveness compared to single interventions. Conclusions: This study suggests that combining probiotics and omega-3 supplementation with USRPT leads to synergistic improvements in sprint swimming performance, enhancing anaerobic power and recovery beyond what is achieved with individual interventions. This integrated approach may provide a practical strategy for competitive swimmers seeking to optimize their performance. Future studies should incorporate mechanistic markers, longer intervention durations, and diverse athlete populations to clarify further and extend these findings. Full article

This paper introduces a novel bio-inspired metaheuristic algorithm, named the sharpbelly fish optimizer (SFO), inspired by the collective ecological behaviors of the sharpbelly fish. The algorithm integrates four biologically motivated strategies—(1) fitness-driven fast swimming, (2) convergence-guided gathering, (3) stagnation-triggered dispersal, and (4) disturbance-induced escape—which synergistically enhance the balance between global exploration and local exploitation. To assess its performance, the proposed SFO is evaluated on the CEC2022 benchmark suite under various dimensions. The experimental results demonstrate that SFO consistently achieves competitive or superior optimization accuracy and convergence speed compared to seven state-of-the-art metaheuristic algorithms. Furthermore, the algorithm is applied to three classical constrained engineering design problems: pressure vessel, speed reducer, and gear train design. In these applications, SFO exhibits strong robustness and solution quality, validating its potential as a general-purpose optimization tool for complex real-world problems. These findings highlight SFO’s effectiveness in tackling nonlinear, constrained, and multimodal optimization tasks, with promising applicability in diverse engineering scenarios. Full article

This study explores the identification, characterization, and biological evaluation of angiotensin I-converting enzyme (ACE)-inhibitory peptides derived from enzymatic hydrolysates of crucian carp swim bladders. Following sequential purification by size-exclusion and reversed-phase chromatography, two bioactive peptides—Hyp-Gly-Ala-Arg (Hyp-GAR) and Gly-Ala-Hyp-Gly-Ala-Arg (GA-Hyp-GAR)—were identified using ultra-high-performance liquid chromatography coupled with linear ion trap–Orbitrap tandem mass spectrometry. The synthetic peptides demonstrated potent ACE-inhibitory activity in vitro, with IC₅₀ values of 12.2 μM (Hyp-GAR) and 4.00 μM (GA-Hyp-GAR). Molecular docking and enzyme kinetics confirmed competitive inhibition through key interactions with ACE active site residues and zinc coordination. In vivo antihypertensive activity was evaluated in spontaneously hypertensive rats, revealing that GA-Hyp-GAR significantly reduced systolic blood pressure in a dose-dependent manner. At a dose of 36 mg/kg, GA-Hyp-GAR reduced systolic blood pressure by 60 mmHg—an effect comparable in magnitude and timing to that of captopril. Mechanistically, GA-Hyp-GAR modulated levels of angiotensin II, bradykinin, endothelial nitric oxide synthase, and nitric oxide. A 90-day subchronic oral toxicity study in mice indicated no significant hematological, biochemical, or histopathological alterations, supporting the peptide’s safety profile. These findings suggest that GA-Hyp-GAR is a promising natural ACE inhibitor with potential application in functional foods or as a nutraceutical for hypertension management. Full article

Background: This study aimed to compare the effects of an eight-week horizontal versus vertical vector resistance training program on swim start performance and lower-limb neuromuscular function in competitive swimmers. Methods: A total of 16 collegiate swimmers (14 males and 2 females; height: 176.3 ± 10 cm; body mass: 68.8 ± 10.3 kg; age: 20.5 ± 2.3 year) were assigned to either a horizontal vector training (HOR) or a vertical vector training (VER) group and completed an eight-week training program. Pre- and post-intervention assessments included flight time, flight distance, underwater speed, 15 m swim speed, 25 m swim speed, and force–time metrics within both concentric and eccentric phases of the countermovement jump and squat jumps. Results: No group or interaction effects were observed. However, time effects were found for flight distance (↑ 4.1–5.5%), flight time (↑ 6.2–12%), 15 m swim speed (↑ 0.3–0.7%), and jump performance. The HOR showed more favorable within-group trends in regards to swim start performance and concentric performance of countermovement and squat jumps. Moderate correlations (r = 0.450–0.476) were found between changes in concentric jump variables and 15 m swim speed. Conclusions: These results suggest that both vertical and horizontal vector resistance training can improve lower-limb neuromuscular performance and swim start performance. Full article

The adverse impacts of invasive salmonids on native galaxiids are well documented at the population level in the freshwater ecosystems of the Southern Hemisphere. However, the mechanism underlying these interactions and sub-lethal effects of salmonids on native galaxiids at the individual level remain poorly understood. In this study, a series of controlled experiments was conducted to assess sub-lethal interactions between invasive brown trout (Salmo trutta) and the native Galaxias platei at an individual level. The microhabitat preferences of G. platei were evaluated in response to potential competition with juvenile brown trout and predation risk from piscivorous adults. In addition, the swimming capacity of G. platei was assessed to determine their ability to escape predation. The results show that at increasing densities of juvenile brown trout, G. platei fails to increase refuge use and are more frequently observed in open habitats. Furthermore, G. platei juveniles exhibit significantly lower swimming capacity compared to brown trout. In the presence of predatory trout, G. platei does not display a heightened preference for refuge habitats. These findings suggest that the behavioral response of G. platei could be insufficient to reduce competition and predation risks posed by brown trout and potentially other salmonids. Full article

Swimming goggles still face numerous challenges in practical use, including deterioration and failure of anti-fog coatings, residual water marks on lens surfaces, and relatively short service life in complex environments. When swimming outdoors during winter, goggles also present an icing problem. To address these problems and enhance the performance of swimming goggles, this study employs a combination of plasma cleaning and mechanical spraying methods, utilizing HB-139 SiO₂ to modify the surface of goggle lenses, thereby fabricating lenses with superhydrophobic properties. The changes in lens surfaces before and after friction and immersion treatments were characterized using three-dimensional profilometry and scanning electron microscopy, further investigating the hydrophobic, drag-reducing, wear-resistant, and anti-icing properties of the lenses. Experimental results demonstrate that SiO₂ can enhance the hydrophobic, drag-reducing, durability, and anti-icing performance of the lenses. Under standard conditions, the contact angle of modified samples reached 162.33 ± 3.15°, representing a 48.77 ± 2.15% improvement over original samples. Under friction conditions, modified samples exhibited a 45.86 ± 2.53% increase in contact angle compared to original samples, with Sa values decreasing by 58.64 ± 3.21%. Under immersion conditions, modified samples showed a 54.37 ± 2.44% increase in contact angle relative to original samples. The modified samples demonstrated excellent droplet bouncing performance at temperatures of −10 °C, 10 °C, and 30 °C. De-icing efficiency improved by 14.94 ± 2.37%. Throughout the experimental process, SiO₂ demonstrated exceptional hydrophobic, drag-reducing, durability, and anti-icing capabilities. This establishes a robust foundation for the exemplary performance of swimming goggles in both training and competitive contexts. Full article

Triathlon is a multi-sport event that combines swimming, cycling and running. The distances vary and the physiological demands are high. Objectives: This review compiles information on nutritional strategies and ergogenic supplements for triathlon training, competition and recovery. It aims to provide an understanding of the specific challenges and needs of the sport to help triathletes and coaches optimise performance through effective training and nutrition plans. Methods: English-language publications were searched using the keywords triathlon, nutrition, recovery and ergogenic aids, alone or in combination, in databases. Results: Maintaining good glycogen levels, consuming enough carbohydrates and staying properly hydrated are key to athletic performance, especially for triathletes. Education regarding nutrition, the role of probiotics and supplements, and diet modification for the enhancement of performance and recovery are pivotal considerations. Conclusions: Triathletes are at risk of RED-S due to negative energy balance and high fibre/plant protein diets, especially women. Optimising muscle glycogen through tailored diet and training, especially pre- and in-race nutrition, including carbohydrate loading and hydration strategies, is critical. Education is needed to improve post-exercise nutrition, while probiotics and certain supplements may aid performance and recovery. Dietary support is important for resistance training to optimise performance and recovery. Full article

Background: Objective evaluation of the swimming start is crucial for sprint performance improvement. Traditional visual assessment of its phases—reaction, take-off, flight, and underwater glide—lacks precision. This study addresses the need for more integrated and accessible biomechanical tools by validating IQ LAB software (Version 250319), which is embedded in the SwimPro system and enables immediate video-based motion analysis without external processing. Existing tools like Dartfish (ProSuite 4.0) require separate video handling and licensing, whereas IQ LAB offers a built-in, streamlined solution suitable for applied environments. Methods: We evaluated the concurrent validity of the IQ LAB software, a desktop 2D motion analysis tool, using Dartfish (ProSuite 4.0) as the gold standard. The reliability was assessed using intrarater temporal stability and interrater agreement, considering selected kinematic parameters related to the swimming kick start (to 5 m). A sample of 13 competitive male swimmers (age 17.2 ± 1.1 years) was analyzed across two sessions. Concurrent validity was assessed by comparing IQ LAB outputs to those from Dartfish software in the sagittal plane. Intrarater reliability was measured using a test–retest design across two sessions spaced 7 days apart. Interrater reliability involved two independent raters analyzing the same video data using IQ LAB. Results: IQ LAB and Dartfish kinematic parameters demonstrated strong agreement (Pearson r ≥ 0.95), with no significant systematic differences. The intrarater and interrater reliability were excellent (ICC ≥ 0.94, 95% CI included). The test–retest reliability of the selected parameters across seasons also showed excellent reproducibility (ICC ≥ 0.93). Conclusions: IQ LAB software provides a valid and reliable 2D kinematic assessment of the swimming kick start, offering a practical and accessible tool for coaches and researchers. This study introduces a novel validated software solution for biomechanical analysis in swimming starts. Full article

This case report analyses the physiological changes of a nine-time world champion triathlete over a competitive season. The triathlete, aged 34, resumed training after a 3-month injury-related break. The study monitored key physiological variables at three points: pre-season (PRE), base period (BASE), and peak performance (PEAK). The athlete trained an average of 25,000 m swimming, 400 km cycling, and 90 km running weekly. Incremental cycling tests were performed at each stage, measuring power output, oxygen uptake (VO₂), ventilatory thresholds (VT1, VT2), muscle oxygen saturation (SmO₂), heart rate, and lactate levels. Results showed significant improvements in relative power output (+37.2% at VT1), VO₂ max (+12.6%), and body composition (body fat reduced from 10.43% to 7.33%). Heart rate and lactate concentration remained stable, while SmO₂ showed a greater difference between VT2 and peak performance. The triathlete achieved top-10 finishes in all key events, including a win at the Ironman 70.3 World Championship. The findings suggest that elite triathletes can regain peak performance after injury through structured training, with improvements in ventilatory efficiency and body composition contributing to better competition results. This study provides valuable insights for coaches on the recovery and performance optimization of elite triathletes. Full article

Background: Tapering, a period of reduced training load following intense training, contributes to performance enhancement. However, research on recovery status during tapering is limited. This study investigates the impact of recovery status on race performance. Methods: Total quality recovery (TQR) scale scores were monitored over two seasons in 22 college competitive swimmers (age: 19.7 ± 1.8 years), including 6 females. They participated voluntarily in the study. Rolling averages (TQRra) and exponentially weighted moving averages (TQRewma) over 7, 14, 21, and 28 days before the race were calculated. Performance data from 550 race days were analyzed by quartiles, and odds ratios were computed for TQR-related variables against race performance improvements. Results: The median TQR was 11 (interquartile range: 10–13). Seasonal bests were achieved in 31.6% of races (174 of 550). The highest odds ratios (ORs) for performance improvement in the highest quartile (Q4) of TQR and z-TQR were 3.13 (p < 0.001) and 4.35 (p < 0.001), respectively. Significant ratios for TQRewma were observed for 7d:21d (OR: 2.62, p < 0.001) and 7d:28d (OR: 2.48, p < 0.001) comparisons. Conclusions: Better recovery status on race day has been associated with improved swimming performance. Additionally, optimizing the TQRewma ratio of the most recent 7 days compared to the preceding 21 to 28 days may further enhance race performance. It highlights the need to monitor an athlete’s recovery over several weeks as an important pre-race strategy. Full article

Background: Motivation is a crucial factor in maintaining athletic performance and preventing dropout among competitive athletes. This process is influenced by both physical and psychosocial factors, which interact and shape decision—making regarding continued participation or withdrawal from sports. Aim: This study examines the motivational level of competitive swimmers in Romania, related to the dropout perspective. Methods: In order to conduct the research, the AMI (Achievement Motivation Inventory)—a validated psychometric tool was used in two distinct phases, conducted six months apart. The study included N = 20 swimmers, finalists and medalists in national swimming competitions. The intervention consisted of motivational coaching, personalized training plans, and the development of mental skills. Results: The results highlighted significant improvements in dimensions such as success confidence, compensatory effort, and goal-setting, indicating the positive effects of the intervention on athletes’ motivation. Inferential analysis using Student t-test confirmed significant differences between the initial and final assessments, for eagerness to learn (p = 0.035), status orientation (p = 0.03) and the Wilcoxon test revealed significant difference for general motivational index (p = 0.020). Conclusions: The findings underscore the importance of psychological approaches in training high-performance athletes, showing that maintaining motivation and clarifying goals are essential factors in preventing sports dropout. The conclusions of this research can serve as a foundation for developing coaching strategies aimed at supporting continuity in performance swimming and reducing the dropout rate among competitive swimmers. Our findings confirm similar studies emphasizing the role of the training patterns and coach influence not just on the performing athlete, but also on his psychosocial individual development. Full article

The aim of this study was to analyze the joint characteristics of the foot and ankle in competitive swimmers aged 16–18 and 19–24 years and their relationship with the presence of muscle pain during swimming. A total of 74 swimmers were evaluated: 38 ‘junior’ (16–18 years) and 36 ‘senior’ (19–24 years). The following parameters were recorded: ankle dorsiflexion, rearfoot mobility, first metatarsophalangeal dorsiflexion, presence of hallux valgus, foot posture, first ray mobility, arch height, and plantar pressure. Additionally, the frequency and location of muscle pain in the triceps surae were analyzed. A cluster analysis was performed to identify variables that differentiated both groups. Ankle dorsiflexion was limited in both groups, with a greater restriction observed in adults (p < 0.001 with an extended knee; p < 0.014 with a flexed knee). The predominant foot type was the cavus foot. The most common pain was localized in the triceps surae, followed by the plantar musculature, with no significant differences between groups. Swimmers exhibited gastrocnemius shortening, which could limit ankle dorsiflexion and contribute to the onset of muscle pain in the leg and foot. These findings suggest the importance of incorporating lower limb flexibility strategies into the training of competitive swimmers. Full article

Objectives: To investigate performance development and variety in swimming strokes of female swimmers from early junior to elite age. Methods: A total of 194,788 race times of female 200 m swimmers representing 77 nations were ranked at peak performance age and clustered into world-class finalists (>850 swimming points), international-class (750–850), national-class (650–750) and regional-class swimmers (550–650). Annual best times for each swimming stroke were retrospectively extracted throughout adolescence from 13 years of age. Longitudinal performance development and differences between the swimmers’ main and their secondary swimming strokes were analyzed using linear mixed model. Results: World-class freestyle swimmers show significantly (p ≤ 0.042) higher swimming points across all age categories compared to international-, national- and regional-class swimmers. Linear mixed model analysis indicates a significant performance progression for international- and national-class freestyle swimmers up to the 19–20-year-old category (p ≤ 0.038), but an earlier plateau was observed for regional-class swimmers (p = 0.714). Comparing main and secondary swimming strokes, freestyle swimmers show the highest degree of specialization. For breaststroke and individual medleys, specialization increases with increasing performance level and the closer an athlete is to elite age. World-class butterfly and backstroke finalists show the lowest specializations in terms of the smallest number of significant differences compared to performances in their secondary swimming strokes. Conclusions: Higher ranked swimmers show a greater degree of specialization. As different specialization patterns are evident for the various swimming strokes, decision makers and talent specialists should align development guidelines accordingly and base them on the most advantageous combinations of swimming strokes. Full article