Key performance indicators related to strength, endurance, flexibility, anthropometrics, and Swimming performance for competitive aquatic lifesaving

The aim of the study was to investigate key performance indicators for the individual pool-based disciplines of competitive lifesaving regarding strength, flexibility, sprint and endurance swimming performance, anthropometric characteristics, and technical skills specific to competitive lifesaving. Data were collected from Swiss national team members (seven males: age 19 ± 2 yrs, body mass 77 ± 11 kg, body height 177 ± 7 cm and seven females age 21 ± 5 yrs, body mass 64 ± 6 kg, body height 171 ± 4 cm) competing at the 2019 European lifesaving championships. Potential key performance indicators were assessed with race times derived from the 2019 long-course season using Spearman's correlation coefficient. Large and significant correlations showed that sprint, i.e., 50 m freestyle performance (r ≥ 0.770), was related to race time of all pool-based disciplines, rather than endurance swimming performance. Additionally, significant correlations revealed upper body strength, i.e., bench press (r ≥ -0.644) and pull (r ≥ -0.697), and leg strength (r ≥ -0.627) as key performance indicators. Importance of the lifesaving-specific skills, anthropometric characteristics, and core strength varied between the disciplines. Flexibility was not significantly related to race times of competitive lifesaving. The present study showed that sprint swimming performance, upper body, and leg strength are particularly important for competitive lifesaving. As other physical and technical requirements varied between the pool-based disciplines, coaches may use the present key performance indicators to establish training guidelines and conditioning programs as well as prioritize skill acquisition in training to specifically prepare athletes for their main disciplines

SEMG MEASUREMENTS ON LAND AND IN WATER PRIOR TO AND AFTER 60- 90 MINUTES OF SUBMERSION (SWIMMING) ARE HIGHLY RELIABLE

The purpose of this study was to investigate the reliability of surface electromyography (sEMG) measurements after being submerged (swimming) for 60-90 minutes. Isometric maximal voluntary contractions (MVC) on land and in water were collected of eight muscles in three males and three females (mean age 22.5±4.5 years). A paired samples t-test showed no significant differences in the mean MVC signal between pre and post test after prolonged water submersion (

Performance Development of European Swimmers Across the Olympic Cycle.

The aims of the study were to (1) quantify the performance development of race times and key performance indicators of European swimmers across the last Olympic cycle (from 2016 to 2021) and (2) provide reference values for long-course swimming pool events for both sexes from 50 m to 1,500 m including butterfly, backstroke, breaststroke, freestyle, and individual medley. Individual events from the 2016 and 2021 European swimming championships were included. Specifically, 246 men (age: 24.2 ± 3.4 years, FINA points: 890 ± 40) and 256 women races (age: 24.2 ± 4, FINA points: 879 ± 38) of the finalists were recorded and key performance indicators and split times analyzed. Performance differences in finalists of the 2016 and 2021 European championships were determined by an independent t-test and Cohen's d effect size. Reference values were retrieved from 2021 European championship finalists and are provided for all key performance indicators. Race times improved significantly (P 1) in 14 (men) and 6 (women) out of 16 events. Improvements were primarily evident in 100 m and 200 m events for males, as well as BR and sprint events for female swimmers. While start times improved in 15 (men) and 14 (women) events, turn times remained inconclusive in both sexes. Generally, breakout distances increased. Clean swimming velocities were faster in 12 (men) and 5 (women) events. In particular, for alternating swimming strokes, i.e., backstroke and freestyle, effect sizes indicated improved swimming efficiency with an inverse relationship between reduced stroke rate and increased distance per stroke. Coaches and performance analysts may use the present reference values as comparative data for race analyses and to specifically prepare swimmers for the various race sections. Data on the performance development should be used to analyze swimmers' potential and set goals for the various events and the next Olympic cycle

KNEE AND ANKLE MUSCLES COACTIVATIONS IN BREASTSTROKE SWIMMING KICK AND RECOVERY: EXPLORATORY APPROACH

The specificities of body position in breaststroke induce important lower limbs solicitations for the swimmers to propel themselves efficiently. Coactivations around the knee and ankle might appear during the powerful leg extension (i.e. push) and for leg replacement (i.e. recovery). The purpose of this exploratory study is to determine muscle activations and coactivations during these two phases at three different velocities. The EMG of four muscles was recorded (BF, RF, GAS and TA). The results showed important activations of the four muscles in the push, contrary to the recovery. However, no significant differences were found for the coactivations in the two phases and for the three velocities. These findings denoted the important resistances occasioned by aquatic environment, both in push and recovery phases, necessitating muscle coactivations to stabilise joints

Key Factors Related to Short Course 100 m Breaststroke Performance.

BACKGROUND AND AIM: To identify kinematic variables related to short course 100 m breaststroke performance. METHODS: An automatic race analysis system was utilized to obtain start (0-15 m), turn (5 m before the wall until 10 m out), finish (95-100 m), and clean swimming (the rest of the race) segment times as well as cycle rate and cycle length during each swimming cycle from 15 male swimmers during a 100 m breaststroke race. A bivariate correlation and a partial correlation were employed to assess the relationship between each variable and swimming time. RESULTS: Turns were the largest time contributor to the finishing time (44.30 ± 0.58%), followed by clean swimming (38.93 ± 0.50%), start (11.39 ± 0.22%), and finish (5.36 ± 0.18%). The finishing time was correlated (p < 0.001) with start segment time (r = 0.979), clean swimming time (r = 0.940), and 10 m turn-out time (r = 0.829). The clean swimming time was associated with the finishing time, but cycle rate and cycle length were not. In both start and turns, the peak velocity (i.e., take-off and push-off velocity) and the transition velocity were related to the segment time (r ≤ -0.673, p ≤ 0.006). CONCLUSIONS: Breaststroke training should focus on: (I) 15 m start with generating high take-off velocity, (II) improving clean swimming velocity by finding an optimal balance between cycle length and rate, (III) 10 m turn-out with maintaining a strong wall push-off, and (IV) establishing a high transition velocity from underwater to surface swimming

Outsourcing Swimming Education—Experiences and Challenges

In Norway, swimming and lifesaving education (swimming education) is an obligatory part of physical education, with explicit learning aims after grade four. After recent reports of Norwegian pupils achieving low scores in swimming abilities, the Government has outlined strategies for improving swimming education. There is a notable trend toward using external providers in delivering swimming education. This article examines the outsourcing of swimming education in Norwegian primary schools. Eighteen semi-structured interviews were conducted with school leaders, physical education teachers and swimming instructors involved in outsourcing arrangements. The outsourcing was organized through private providers, municipalities, or local swimming clubs. Data were analyzed thematically and separated into highlighted areas of outsourcing practices. The results showed that outsourcing may be a solution for schools that lack staff with swimming experience and knowledge. It also indicates that teacher courses, professional development through collaboration, and strategies for measuring quality would improve swimming education

Muscle activation and kinematics in contemporary breaststroke swimming

This thesis consists of five studies, the main objectives of which were to establish a reliable method for conducting surface electromyography (EMG) in water over prolonged submersion (Study 1); to develop a specific method for dividing the contemporary breaststroke leg kick into phases independent of the different techniques used by elite swimmers (Study 2); and to identify the role of neuromuscular activity in effort (Study 3) and performance levels (Studies 4 and 5) in elite contemporary breaststroke swimming. In total, twenty-one participants (twelve students and nine elite swimmers) volunteered to participate. Muscle activation was measured with EMG from eight muscles on the right side of the body. Kinematic variables were measured from twenty-one retro-reflective markers placed on the swimmer's body. Data from these markers were captured in 3D using automatic motion tracking

Differences between elite and sub-elite swimmers in a 100 m breaststroke: A new race analysis approach with time-series velocity data

The purpose of the present study was to investigate differences in a 100 m breaststroke time-trial between elite and sub-elite swimmers. Elite and sub-elite male swimmers (seven each; 772.1 ± 35.2 and 610.6 ± 24.7 FINA point, respectively) performed 100 m breaststroke, which was recorded by a multi-camera system that provided the mean and time-series velocity data in the glide, pull-out, and clean-swimming segments. The mean velocity in each segment was compared between the groups using an independent-samples t-test (for the 1st lap) and two-way mixed-design ANOVA (for the 2nd—4th laps), which suggested a larger mean clean-swimming (in all laps; 7–11% difference) and glide (in the 2nd and 3rd lap; about 13% difference) velocity for the elite swimmers. The time-series data displayed faster velocity in elite swimmers than in the sub-elite group during the first part (up to 40% time) of the glide segment (p < 0.05). Differences in the clean-swimming segment between the groups were observed (p < 0.001) apart from the first 5–15% time of the segment. No differences in the pull-out and at the beginning of the clean-swimming imply that coaches and swimmers should not assume that a good clean-swimming technique also guarantees fast velocity in these segments

Reliability of the active drag assessment using an isotonic resisted sprint protocol in human swimming.

The purpose of the presents study was to investigate the reliability of the active drag (Da) assessment using the velocity perturbation method (VPM) with different external resisted forces. Eight male and eight female swimmers performed 25 m sprints with five isotonic loads (1-2-3-4-5 kg for females; 1-3-5-7-9 kg for males), which were repeated twice on different days. The mean velocity and semi-tethered force were computed for each condition, and the free-swimming maximum velocity was estimated with load-velocity profiling. From the obtained variables, Da at the maximum free-swimming condition was calculated using VPM. Absolute and typical errors and the intra-class correlation (ICC) were calculated to assess test-retest reliability. 95% confidence interval (95% CI) lower bound of ICC was larger than 0.75 in 3, 4 (females only) and 5 kg trials in both sexes (corresponding to 37-60 N additional resistance; all p < 0.001), which also showed small absolute and relative typical errors (≤ 2.7 N and ≤ 4.4%). In both sexes, 1 kg load trial (16-17 N additional resistance) showed the lowest reliability (95% CI of ICC; - 0.25-0.83 in males and 0.07-0.94 in females). These results suggested that a tethered force of 37-60 N should be used to assess Da using VPM

Validation of the Polar OH1 and M600 optical heart rate sensors during front crawl swim training.

PURPOSE:The Polar OH1 is an optical heart rate (HR) sensor which can be used on different parts of the body. The purpose of the study was to evaluate the validity of the OH1 as well as a wrist worn heart rate device (Polar M600) during swimming. METHODS:Twenty-six well-trained competitive swimmers performed a regular training session including different swimming intensities. During the training the swimmers wore a H10 HR sensor with Polar Pro strap (H10) underneath the swim suit, a Polar OH1 optical HR sensor (OH1) underneath the swimming cap at the temple, and a sports watch with optical HR sensor, Polar M600 smart watch (M600) on the wrist. RESULTS:No difference in HRmax, HRmean and HRmin between H10 and OH1 were evident. The HRmax and HRmean obtained by the M600 was significantly lower than the obtained by H10 and OH1 (p < 0.05). The ICC showed mostly excellent agreements between H10 and OH1 and poor to good agreements between H10 and M600. Bland-Altmann plot for M600 vs. H10 indicates upper and lower limits of agreement of -53.0 to 33.9 beats per minute. For OH1 vs. H10 the upper and lower limits of agreement were -26.9 to 24.7 beats per minute. CONCLUSION:The Polar OH1 optical HR sensor is a valid tool to monitor HR of different intensities during swimming whereas the Polar M600 smart watch as a wrist worn device is less accurate