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The presence of oxygen in active muscles dictates substrate metabolism which is crucial for sport performance. However, it's information in dragon boat races is limited. This study aimed to evaluate muscle oxygenation and energy substrate utilization during 200-m and 500-m dragon boat races among elite athletes. Ten male dragon boat athletes participating in international competitions (age 26.60 ± 3.20 years, weight 79.54 ± 3.36 kg, height 174.80 ± 5.67 cm) completed 200-m and 500-m simulated race trials on an ergometer in a randomized, counterbalance, crossover fashion, with a 2-day separation. Near-infrared spectroscopy (NIRS) monitors were placed on the biceps brachii (BB) and latissimus dorsi (LD) to investigate tissue saturation index (TSI), oxyhemoglobin concentration (O2Hb), deoxyhemoglobin concentration (HHb), and total hemoglobin (tHB) during the trials, and gas analyzer was employed to evaluate energy substrate utilization. The results revealed that during 200-m and 500-m races, TSI, O2Hb, and tHb in the BB significantly decreased (P<0.05), whereas HHb significantly increased (P<0.05). In the LD, this change was observed only in 200-m race (P<0.05). When comparing between the distances, all oxygen parameters in the BB were significantly higher in 500-m than 200-m (P<0.05), while in the LD, TSI, O2HB, and tHb were significantly higher (P<0.05). Total energy and energy from carbohydrate were also significantly higher in 500-m than 200-m race (P<0.01). The results of this study indicate that there is difference in muscle oxygenation and energy substrate expenditure during 200-m and 500-m dragon boat races. This disparity may be resulted from different muscle recruitment patterns, as indicated by difference in oxygen parameters in the BB and LD during the races. This study provides new knowledge to the area of paddle sports and offers practical insights that can help coaches and related persons to optimize athletic performance during training and competitions. More researches are required to clarify the mechanisms underlying the differences in muscle oxygenation in different dragon boat race distances. [ABSTRACT FROM AUTHOR]

Purpose: (1) To compare various physiological indicators of performance during a 5 × 1500-m incremental kayak test performed on an ergometer and on-water and (2) to analyze the relationships between these indicators and the actual competition performance of elite sprint kayakers, aiming to provide information to coaches for evaluating and planning training on-water. Methods: A total of 14 male and female German elite sprint kayakers performed an incremental test both on an ergometer and on-water. The tissue saturation index of the musculus (m.) biceps brachii, oxygen consumption, ratings of perceived exertion, and levels of blood lactate were measured and compared with actual racing times. In addition, power output was monitored during ergometer testing only. Results: Oxygen consumption during the fourth (P =.02; d = 0.32) and final (fifth; P <.001; d = 0.32) steps of incremental testing was higher on-water than on the ergometer. The tissue saturation index of the m. biceps brachii was approximately 21% higher at the end of the ergometer test (P =.002; d = 1.14). During the second (P =.01; d = 0.78), third (P =.005; d = 0.93), and fourth stages (P =.005; d = 1.02), the ratings of perceived exertion for ergometer kayaking was higher. During the final step, power output was most closely correlated to 200- (r =.88), 500- (r =.93), and 1000-m (r =.86) racing times (all Ps <.01). Conclusions: During high-intensity kayaking on an ergometer or on-water, the oxygen consumption and tissue saturation index of the m. biceps brachii differ. Furthermore, at moderate to submaximal intensities, the ratings of perceived exertion were higher for ergometer than for on-water kayaking. Finally, of all parameters assessed, the power output during ergometer kayaking exhibited the strongest correlation with actual racing performance. [ABSTRACT FROM AUTHOR]

The need to determine the factors that positively or negatively affect the acquisition of swimming knowledge arose with the development of various swimming programs. The aim of this research was to determine the connection between the level of anxiety and success in the process of motor learning in swimming training program for non-swimmers. A sample of 77 children, aged (11.00±0.71), participated in a swimming training program for non-swimmers for 20 hours according to the standard method used in the Republic of Croatia. In the first and last lesson, the swimming knowledge was determined by means of a scale of eleven grades that describe the level of acquisition of swimming knowledge. Level of anxiety was assessed by modified CSAI-2CSWIM anxiety level questionnaire. Correlation analysis determined that the level of anxiety has a significant negative correlation with performance in all three observed domains, cognitive anxiety -0.273 and -2.46, somatic anxiety -0.384 and -0.337 and self-confidence -0.420 and -0.308 with results on the final test and with progress in swimming learning. The results of the conducted research showed that the level of anxiety has a significant influence on the children’s swimming learning process. [ABSTRACT FROM AUTHOR]

Introduction: Australia is one of the largest surfing nations with over 10% of the population participating; yet there is a paucity of literature analysing the injuries from surfing participation, particularly injuries requiring orthopaedic care. This study retrospectively analyses surfing injuries presenting to a tertiary hospital Emergency Department over a ten-year period with aims of quantifying surfing injuries and investigating injury characteristics requiring orthopaedic input.Methods: A retrospective clinical audit of presentations to Gold Coast Public Hospital Emergency Departments over a ten-year period was conducted using electronic hospital databases. Broad search teams were used to identify presentations, followed by exclusion based on relevance. Subsequent analysis of data was performed to investigate patient demographics and injury characteristics.Results: A total of 2680 surfing related injury presentations were analysed. The median age was 30 years (range 2-77), with 455 females (17%) and 2225 males (83%). Lacerations were the most common injury type (37.9%), followed by ligament injury (21.3%), fractures (12.2%), and contusions (11.4%). The most common areas for lacerations were head/face (59.2%), lower limb (30%), and upper limb (26.5%). Dislocation rate was 4.9%, with shoulder dislocation (76.5%), and patella dislocation (12.1%) being the most common types. 1512 presentations (56.4%) required orthopaedic management. 93.5% did not require admission and were discharged.Conclusion: Over half (56.4%) of surfing injuries were orthopaedic in nature; requiring orthopaedic advice or management. Lacerations, ligament injury, fractures and dislocations were the most commonly managed injuries. This emphasises the importance of understanding the prevalence and characteristics of surfing injuries for an orthopaedic service. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the differences in hand-grip strength and strength-related anthropometric parameters between the highest-performance international paddlers (HILP) and other international paddlers (ILP) in canoe slalom. In male competitors (n=48; 23 canoeists and 25 kayakers) who took part in the 2018 European championship event in canoe slalom in Prague, Czech Republic representing 15 European countries were measured hand-grip strength and strength-related anthropometric parameters two days prior the event. Differences between the group of HILP (medallists from Olympic Games, world championship and European championship in the previous three years and European championship finalists at the same time) and ILP were found. HILP have significantly higher forearm, arm and chest girths than ILP. Moderate or high practical differences and margin statistic differences were found also for hand-grip strength, body weight, body mass index and age. The consistently high-performing paddlers are heavier, have more muscular upper body and are stronger than the other group, while keeping their lower body lean. Therefore, regular upper-body strength training to all canoe slalom paddlers is important but caution is required because body weight over 80 kg may be a limiting factor. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Winter swimming is a new sport discipline. Very little is known, however, about the sex differences, origin, participation and performance of the world's best winter swimmers. Therefore, the study aimed to investigate sex differences in performance and age. Furthermore, it should be determined which country has the fastest swimmers, the highest numbers of participants and the most successful age group athletes in winter swimming. SUBJECTS AND METHODS: A total of 6,477 results from the 25 m events of the IWSA (International Winter Swimming Association) World Cups from 2016-2020 was collected from the official website of IWSA. Data were analyzed using a generalized linear model (GLM) with a gamma probability distribution and identity link function. The 25 m events were carried out in head-up breaststroke style, freestyle and butterfly. The nationalities were grouped into six groups, the five nationalities with the highest number of participants in the 25 m competitions and one group with the other nationalities. The mean time of 25 m races by sex and country of the total sample was compared. For the top 10 comparisons, the best ten athletes from the six groups were selected. The mean time of each top 10 groups was compared by sex and nationality. RESULTS: Men were faster than women for all categories. Swimmers in age group 15-29 years were the fastest, where females were the fastest in age group 15-19 years and males in age group 20-29 years. Women from both Russia and Estonia and men from both Russia and China were the fastest. Both Russian and Chinese males were the fastest in all water categories in the top 10 section in the 25 m events. CONCLUSIONS: In summary, males were faster than females in the IWSA World Cups between 2016 and 2020. The age group of 15-29 years old athletes was the most successful while females had their age of peak performance earlier than males. Russian and Estonian males and Russian females were the overall fastest in the 25 m events in all water categories. Future studies should investigate the optimal anthropometric characteristics of male and female winter swimming sprint athletes and whether there are distinct areas in Russia, Estonia and China, where many international winter swimming athletes originate. [ABSTRACT FROM AUTHOR]

Understanding the effect of risk factors on tourists' hesitation in choosing a destination is vital for successful management in tourism, especially in the pandemic era. Based on protection motivation theory, this study investigated the impact of sport tourists' perceived risk associated with COVID-19 on their hesitation to choose a tourist destination in the context of water sport tourism. Further, we examined whether the relationship changes according to the levels of tourists' destination image. Data from a survey of water sport tourists (n = 312) were analyzed using structural equation modeling and Hayes PROCESS macro with bootstrapping procedures. Findings of this research empirically demonstrated that risk factors influence hesitation in choosing a destination. Furthermore, the moderating effect of destination image on the influences of perceived risks on hesitation was identified. The study's theoretical and practical contributions to the sport tourism literature are also discussed. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate retrospectively the training intensity distribution (TID) among highly trained canoe sprinters during a single season and to relate TID to changes in performance.Methods: The heart rates during on-water training by 11 German sprint kayakers (7 women, 4 men) and one male canoeist were monitored during preparation periods (PP) 1 and 2, as well as during the period of competition (CP) (total monitoring period: 37 weeks). The zones of training intensity (Z) were defined as Z1 [87% VO2peak), as determined by 4 × 1,500-m incremental testing on-water. Prior to and after each period, the time required to complete the last 1,500-m stage (all-out) of the incremental test (1,500-m time-trial), velocities associated with 2 and 4 mmol·L−1 blood lactate (v2[BLa], v4[BLa]) and VO2peak were determined.Results: During each period, the mean TID for the entire group was pyramidal (PP1: 84/12/4%, PP2: 80/12/8% and CP: 91/5/4% for Z1, Z2, Z3) and total training time on-water increased from 5.0 ± 0.9 h (PP1) to 6.1 ± 0.9 h (PP2) and 6.5 ± 1.0 h (CP). The individual ranges for Z1, Z2 and Z3 were 61–96, 2–26 and 0–19%. During PP2 VO2peak (25.5 ± 11.4%) markedly increased compared to PP1 and CP and during PP1 v2[bla] (3.6 ± 3.4%) showed greater improvement compared to PP2, but not to CP. All variables related to performance improved as the season progressed, but no other effects were observed. With respect to time-trial performance, the time spent in Z1 (r = 0.66, p = 0.01) and total time in all three zones (r = 0.66, p = 0.01) showed positive correlations, while the time spent in Z2 (r = −0.57, p = 0.04) was negatively correlated.Conclusions: This seasonal analysis of the effects of training revealed extensive inter-individual variability. Overall, TID was pyramidal during the entire period of observation, with a tendency toward improvement in VO2peak, v2[bla], v4[bla] and time-trial performance. During PP2, when the COVID-19 lockdown was in place, the proportion of time spent in Z3 doubled, while that spent in Z1 was lowered; the total time spent training on water increased; these changes may have accentuated the improvement in performance during this period. A further increase in total on-water training time during CP was made possible by reductions in the proportions of time spent in Z2 and Z3, so that more fractions of time was spent in Z1.

Freshwater sports involve a wide range of practices leading to contact with soil and water that can entail exposure to agents of potential infectious diseases. The pathogens can be multiple (bacteria, parasites, viruses, fungi), and be either well-known or more unfamiliar and exotic. We conducted a literature review to describe various infections contracted following exposure to water and mud during freshwater sport activities. Out of the 1011 articles identified, 50 were finally included. Our findings encompassed bacterial infections (leptospirosis and gastrointestinal infections); parasitic infections (schistosomiasis, cercarial dermatitis); viral infections (norovirus and other gastrointestinal viruses; seaweed contamination; and fungal infections. These infections were reported in various countries worldwide among diverse freshwater sport activities, including swimming, surfing, kayaking, as well as extreme sports such as adventure races and mud runs. Water sports in freshwater can expose participants to infectious risks according to geographical location and type of sport. Because regular sport practice is beneficial for health, freshwater sports should not be avoided due to potential exposure to pathogens; that much said, certain precautions should be taken. In addition to adoption of preventive measures, participants should be informed about infectious risks and seek medical advice if symptoms appear after exposure. Current guidelines for assessment of bathing water quality do not suffice to ensure comprehensive evaluation of freshwater quality. Event organizers are called upon to pay close attention to environmental factors and meteorological events, to conduct timely sensitization campaigns, and to enforce appropriate safety measures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Objectives The aim of this study was to discover the relationship between the performance of different mechanical movements of rowers, and define its effect on the motor programs of the cyclic movement in athletes living in rural and urban areas. Material and methods Twenty-two male rowers participated in the experiment using a rowing ergometer (Concept2, USA). The experiment consisted of 3 tests examining the maximal power of the pull-ups (MPbpu). The movement mechanogram was registered with a specialized complex Noraxon’s 3D MyoMotion (Noraxon Inc., USA). The software of the complex allowed calculation of the values of the joint angles from the accelerometer data. The Origin Lab 8.5 program was used for the mathematical and statistical processing of the signals from the mechanograms. Results It was found that all experiment participants had a stepped controlled increase in the power of single bar pull-ups leading to a corresponding proportional increase in the frequency of rowing – test 1 and, conversely, a stepped controlled increase in the rowing frequency accompanied by a proportional increase in the power of the bar pull-ups – test 2. The involuntary dependence of the power and the rate was due to the peculiarities of the central cyclic movement programming, according to which the forces and durations of the active and passive bar pull-ups phases were interconnected and regulated together. The voluntary power-rate dependence control led to the breakdown of these links in the motor program of cyclic movements and to the separate control of these parameters. Conclusions Motor programs in cyclic movement may be created in the same pattern in tope level sport and recreation, as well in different environmental conditions – gym halls (movement simulators), professional and recreational water sport tracks.

Pantelis Theodoros Nikolaidis,1 Caio Victor Sousa,2 Beat Knechtle3,4 1Exercise Physiology Laboratory, Nikaia, Greece; 2Graduate Program in Physical Education, Catholic University of Brasília, Brasília, Brazil; 3Medbase St. Gallen Am Vadianplatz, St. Gallen, Switzerland; 4Institute of Primary Care, University of Zurich, Zurich, Switzerland Aim: The aim of the present study was to investigate the relationship of wearing a wetsuit with sex, age group, nationality, calendar year, and performance in crossing the “Strait of Gibraltar”(14.3 km). Materials and methods: A sample of 1,130 open-water (females, n=180, age 35.9±11.9 years; males, n=950, age 40.0±10.2 years) ultra-distance swimmers crossing the “Strait of Gibraltar” since 1950 was analyzed. Results: Male, older, and Spanish swimmers used wetsuits more often than female, younger, and athletes of other nationalities, respectively, and the use of the wetsuit has increased during the past three decades. Swimmers with wetsuits were faster than those without. Male athletes aged 30–34 years were faster than athletes >60 years. Female athletes were younger than male athletes, and swimmers with wetsuits were older than those without. The Spanish were faster than the American swimmers and athletes from other nationalities, and the American swimmers were the oldest. Conclusion: In summary, swimmers were faster when using a wetsuit, and local Spanish swimmers were the fastest and also used wetsuits most frequently. Male and older swimmers used wetsuits more often than other swimmers, and the use of wetsuits has increased in the last three decades. Keywords: aging, master athlete, endurance, water sport, physiology, gender

The objective of the current study was to assess the reliability of paddling tests involving pivot turns and their relationship to performance level in elite slalom canoeists. Eighteen elite (national level, N = 9) and high performing elite (HPE – international level, N = 9) slalom canoeists performed timed paddling tests with a different number of pivot turns over progressively longer distances (3 x 40 m, 80 m, 200 m). The tests provided high test–retest reliability over time (ICC = ~0.9, CV = ~2%). HPE canoeists were faster in all tests than elite canoeists, however the largest differences were found over 200 m with 10 pivots (- 8.7 s, P < 0.001, Hedges' g = 1.87). The time of pivoting on their preferred side was similar between elite and HPE canoeists (∆ 0.2 s, P = 0.162, g = 0.62); however, pivoting on their non-preferred side was significantly faster (- 0.6 s, P = 0.004, g = 1.44) in HPE canoeists. The results showed that paddling tests with simple technical elements clearly distinguished HPE from elite slalom paddlers. The paddling test over 200 m predicted best the performance level and is suitable for training practice in elite slalom canoeists. [ABSTRACT FROM AUTHOR]

Copyright of Facta Universitatis: Series Physical Education & Sport is the property of Facta Universitatis, Series Physical Education & Sport and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water polo players require a high level of upper-extremity strength, flexibility and coordination to achieve a peak level of throwing performance. Increased levels of shoulder proprioceptive acuity, strength and range of motion (ROM) have been previously associated with higher sporting performance. A coach-rating scale, used to quantify an athlete's kicking proficiency in soccer; was adapted in the current study to measure each coach's subjective expert opinion regarding athletes' throwing mechanics, velocity, and accuracy. To examine this hypothesis shoulder proprioception acuity of 18 water polo players was measured both in-water and on-land using an AMEDA apparatus and correlated with coach-rated throwing performance and clinical measures of shoulder strength and ROM. There was a moderate positive correlation between the in-water and the on-land proprioception acuity (r = 0.47, p < 0.05). The in-water score showing a strong positive correlation with coach rated throwing mechanics (r = 0.68, p < 0.05) and velocity (r = 0.75, p = 0.02), suggesting that superior proprioception acuity contributed to fast, mechanically-efficient throwing. These findings support the notion that in-water proprioceptive acuity is an important determinant of the throwing performance achieved by water polo athletes and its measurement may be a valuable adjunct to current athlete screening. [ABSTRACT FROM AUTHOR]

Objectives. The aim of this study was to discover the relationship between the performance of different mechanical movements of rowers, and define its effect on the motor programs of the cyclic movement in athletes living in rural and urban areas. Materials and method. Twenty-two male rowers participated in the experiment using a rowing ergometer (Concept2, USA). The experiment consisted of 3 tests examining the maximal power of the pull-ups (MPbpu). The movement mechanogram was registered with a specialized complex Noraxon’s 3D MyoMotion (Noraxon Inc., USA). The software of the complex allowed calculation of the values of the joint angles from the accelerometer data. The Origin Lab 8.5 program was used for the mathematical and statistical processing of the signals from the mechanograms. Results. It was found that all experiment participants had a stepped controlled increase in the power of single bar pull-ups leading to a corresponding proportional increase in the frequency of rowing – test 1 and, conversely, a stepped controlled increase in the rowing frequency accompanied by a proportional increase in the power of the bar pull-ups – test 2. The involuntary dependence of the power and the rate was due to the peculiarities of the central cyclic movement programming, according to which the forces and durations of the active and passive bar pull-ups phases were interconnected and regulated together. The voluntary power-rate dependence control led to the breakdown of these links in the motor program of cyclic movements and to the separate control of these parameters. Conclusions. Motor programs in cyclic movement may be created in the same pattern in tope level sport and recreation, as well in different environmental conditions – gym halls (movement simulators), professional and recreational water sport tracks. [ABSTRACT FROM AUTHOR]

This study investigated the effectiveness of a self-selected (SS) warm-up on 500 m sprint kayak performance (K500) compared to continuous (CON) and intermittent high intensity (INT)-type warm-ups. Twelve nationally ranked sprint kayakers (age 17.7 ± 2.3 years, mass 69.2 ± 10.8 kg) performed CON (15 min at the power at 2 m·mol−1), INT (10 min at 2 m·mol−1, followed by 5 × 10 s sprints at 200% power at VO2max with 50 s recovery at 55% power at VO2max), and SS (athlete’s normal competition warm-up) warm-ups in a randomised order. After a five-minute passive recovery, K500 performance was determined on a kayak ergometer. Heart rate and blood lactate (BLa) were recorded before and immediately after each warm-up and K500 performance. Ratings of perceived exertion (RPE) were recorded at the end of the warm-up and K500. BLa, heart rate, and RPE were generally higher after the INT than CON and SS warm-ups (p < 0.05). No differences in these parameters were found between the conditions for the time trial (p > 0.05). RPE and changes in BLa and heart rate after the K500 were comparable. There were no differences in K500 performance after the CON, SS, or INT warm-ups. Applied practitioners can, therefore, attain similar performance independent of warm-up type.

In open-water swimming events with non-elite swimmers held in the USA, but not in Europe, women were faster than men. We examined the sex difference in elite long-distance open-water swimming races and the role of nationality by investigating 7,468 swimmers competing in 5 km, 10 km and 25 km FINA races held between 2000 and 2016. More men participated in 10 km and 25 km than in 5km races. Men were faster than women and the sex difference was similar in all race distances. Swimming speed was faster for 5km than for 10km, which in turn was faster than 25km. There was a major effect of nationality on swimming speed at 5 km and 10 km, but not at 25km. No dominance of a particular nationality was observed for all race distances. In summary, men were faster than women in all FINA race distances from 5km to 25km but nationality played no role in the sex difference. [ABSTRACT FROM AUTHOR]

Copyright of Annales de Normandie is the property of Annales de Normandie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the correlations with anthropometry, upper extremity strength, and surfboard paddling performance in recreational and competitive surfers. Twenty-nine recreational and competitive male surfers were assessed for height, mass, relative arm span, relative seated height, relative biacromial width, and skinfolds (Sum7). The upper extremity strength variables assessed were the relative 1-RM pull up and 1-RM dip. The surfboard paddling variables assessed were a 15m sprint-paddling test and a 400m endurance-paddling water-based test. Pearson correlation analysis and independent t-tests were used to compare differences between groups and determine the significant correlations between variables. Sum7 and relative arm span were correlated with speed in all paddling efforts meanwhile the sprintpaddling ability was correlated with the upper extremity strength. Significant differences between competitive and recreational surfers exist in relative arm span and endurance paddle performance. The strong relationships between the physical variables can be used by sports coaches and support staff to influence talent identification, training, and nutrition programs. [ABSTRACT FROM AUTHOR]

Purpose: The main purpose of this study was to analyze the coordination, propulsion and non-propulsion phases in the 100 meter breaststroke race. Methods: Twenty-seven male swimmers (15.7 ± 1.98 years old) with the total body length (TBL) of 247.0 ± 10.60 [cm] performed an all-out 100 m breaststroke bout. The bouts were recorded with an underwater camera installed on a portable trolley. The swimming kinematic parameters, stroke rate (SR) and stroke length (SL), as well as the coordination indices based on propulsive or non-propulsive movement phases of the arms and legs were distinguished. Results: Swimming speed (V100surface breast) was associated with SL (R = 0.41, p < 0.05) and with TBL tending towards statistical significance (R = 0.36, p < 0.07), all relationships between the selected variables in the study were measured using partial correlations with controlled age. SL interplayed negatively with the limbs propulsive phase Overlap indicator (R = -0.46, p < 0.05), but had no significant relationship to the non-propulsion Glide indicator. Conclusions: The propulsion in-sweep (AP3) phase of arms and their non-propulsion partial air recovery (ARair) phase interplayed with V100surface breast (R = 0.51, p < 0.05 and 0.48 p < 0.05) respectively, displaying the importance of proper execution of this phase (AP3) and in reducing the resistance recovery phases in consecutive ones. [ABSTRACT FROM AUTHOR]

Copyright of German Journal of Sports Medicine / Deutsche Zeitschrift fur Sportmedizin is the property of Verein zur Forderung der Sportmedizin Hannover e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background The present study investigated the changes in swimming speeds and sex differences for elite male and female swimmers competing in 5 km, 10 km and 25 km open-water FINA World Cup races held between 2000 and 2012. Methods The changes in swimming speeds and sex differences across years were analysed using linear, non-linear, and multi-level regression analyses for the annual fastest and the annual ten fastest competitors. Results For the annual fastest, swimming speed remained stable for men and women in 5 km (5.50 ± 0.21 and 5.08 ± 0.19 km/h, respectively), in 10 km (5.38 ± 0.21 and 5.05 ± 0.26 km/h, respectively) and in 25 km (5.03 ± 0.32 and 4.58 ± 0.27 km/h, respectively). In the annual ten fastest, swimming speed remained constant in 5 km in women (5.02 ± 0.19 km/h) but decreased significantly and linearly in men from 5.42 ± 0.03 km/h to 5.39 ± 0.02 km/h. In 10 km, swimming speed increased significantly and linearly in women from 4.75 ± 0.01 km/h to 5.74 ± 0.01 km/h but remained stable in men at 5.36 ± 0.21 km/h. In 25 km, swimming speed decreased significantly and linearly in women from 4.60 ± 0.06 km/h to 4.44 ± 0.08 km/h but remained unchanged at 4.93 ± 0.34 km/h in men. For the annual fastest, the sex difference in swimming speed remained unchanged in 5 km (7.6 ± 3.0%), 10 km (6.1 ± 2.5%) and 25 km (9.0 ± 3.7%). For the annual ten fastest, the sex difference remained stable in 5 km at 7.6 ± 0.6%, decreased significantly and linearly in 10 km from 7.7 ± 0.7% to 1.2 ± 0.3% and increased significantly and linearly from 4.7 ± 1.4% to 9.6 ± 1.5% in 25 km. Conclusions To summarize, elite female open-water ultra-distance swimmers improved in 10 km but impaired in 25 km leading to a linear decrease in sex difference in 10 km and a linear increase in sex difference in 25 km. The linear changes in sex differences suggest that women will improve in the near future in 10 km, but not in 25 km. [ABSTRACT FROM AUTHOR]

In La Traversée Internationale du Lac St-Jean, held between 1955 and 2012 in Canada, the fastest women ( r2 = 0.61, p < 0.0001) and men ( r2 = 0.66, p < 0.0001) improved swimming speed over the years but the sex difference remained unchanged at 8.8% ± 5.6% ( r2 = 0.069, p = 0.065). Annually, for the 3 fastest swimmers, both women ( r2 = 0.53, p < 0.0001) and men ( r2 = 0.71, p < 0.0001) improved swimming speed between 1973 and 2012 and the sex difference decreased ( r2 = 0.29, p = 0.0016) from 14.4% ± 11.0% (1973) to 3.7% ± 1.4% (2012). [ABSTRACT FROM AUTHOR]

Open-water swimming is a rapidly growing sport discipline worldwide, and clinical problems associated with long-distance swimming are now better recognized and managed more effectively. The most prevalent medical risk associated with an open-water swimming event is hypothermia; therefore, the Federation Internationale De Natation (FINA) has instituted 2 rules to reduce this occurrence related to the minimum water temperature and the time taken to complete the race. Another medical risk that is relevant to open-water swimmers is heat stroke, a condition that can easily go unnoticed. The purpose of this review is to shed light on this physiological phenomenon by examining the physiological response of swimmers during long-distance events, to define a maximum water temperature limit for competitions. We conclude that competing in water temperatures exceeding 33°C should be avoided. [ABSTRACT FROM AUTHOR]