Crawl Swimming Research Articles

The relationship between maximal lactate accumulation rate and sprint performance parameters in male competitive swimmers.

This study aimed to examine the relationship between the maximal lactate accumulation rate (ċLamax) and sprint performance parameters in male competitive swimmers. Seventeen male competitive swimmers volunteered to perform a 20 m maximal front crawl sprint without pushing off the wall from a floating position. ċLamax was determined by the 20-m sprint time and blood lactate measured before and after the 20 m sprint. For the sprint performance parameter, a 50 m time trial with the front crawl swimming stroke was conducted, and the times taken from 0 to 15 m, 15-25 m, 25-35 m, and 35-45 m were analyzed. A semi-tethered swimming test was conducted to investigate the load-velocity profile of each swimmer. From the load-velocity profile, theoretical maximal velocity (V0), maximal load (L0) and relative maximal load (rL0) were examined. The slope of the load-velocity profile was also determined. According to the results, ċLamax correlated with 50 m front crawl performance (r = -.546, p < .05). Moreover, a higher ċLamax was related to faster 0-35 m section time. Furthermore, ċLamax correlated with L0 (r = .837, p < .01), rL0 (r = .820, p < .01), and load-velocity slope (r = .804, p < .01). ċLamax is a good indicator of 50 m front crawl performance in male swimmers, and higher glycolytic power contributes to the faster time at the beginning of the sprint race. ċLamax could also evaluate the ability of a swimmer to apply force to the water during high-intensity swimming.

Aerobic capacity in swimming, cycling and arm cranking in swimmers aged 11–13 years

BackgroundThis study aimed to compare the aerobic capacity in swimming, cycling and arm cranking in swimmers aged 11–13 years.MethodsEleven swimmers (mean age, 12.1 ± 1.0 years) performed three incremental exercise tests. One of the tests was performed under specific conditions (front crawl swimming), and the other two were under non–specific conditions (cycling and arm cranking). Data on the pulmonary gas exchange were recorded using the portable analyser MetaMax 3B (Cortex, Leipzig, Germany). One-way analysis of variance for repeated measures was employed to test the null hypothesis and determine statistically significant differences between the indicators obtained under specific and non–specific testing conditions. Pearson’s correlation coefficient was calculated to assess the relationships between the indicators of the pulmonary gas exchange.ResultsThe relative peak oxygen uptake (V̇O2peak) value during swimming was 49.3 ± 6.2 mL/kg/min, which was higher than that during arm cranking (39.6 ± 7.3 mL/kg/min; P < 0.01) but lower than that during cycling (54.3 ± 7.8 mL/kg/min; P < 0.01). The peak minute ventilation (V̇Epeak) value during swimming (84.9 ± 12.6 L/min) was higher than that during arm cranking (69.4 ± 18.2 L/min; P < 0.01) but lower than that during cycling (98.4 ± 15.4 L/min; P < 0.01). Strong positive correlations were observed in the absolute and relative V̇O2peak values between swimming and cycling (r = 0.857, P < 0.01; r = 0.657, P < 0.05) and between swimming and arm cranking (r = 0.899, P < 0.01; r = 0.863, P < 0.05). A strong positive correlation was also observed in V̇Epeak values between swimming and arm cranking (r = 0.626, P < 0.05).ConclusionSwimmers aged 11–13 years showed V̇O2peak and V̇Epeak values during the specific swimming test greater than those during arm cranking but lower than those during cycling. However, aerobic capacity parameters measured during specific swimming conditions correlated with those measured during non–specific arm cranking and cycling conditions.

Fast Competitive Swimmers Demonstrate a Diminished Diving Reflex.

Competitive swimmers complete 50-m front crawl swimming without breathing or with a limited number of breaths. Breath holding during exercise can trigger diving reflex including bradycardia and diminished active muscle blood flow, whereas oxygen supply to vital organ such as brain is maintained. We hypothesized that swimmers achieving faster time in 50-m front crawl with limited number of breaths demonstrate a blunted diving reflex of cardiac and active muscle blood flow responses with elevated cerebral perfusion to counteract peripheral and central fatigues. Twenty-eight competitive swimmers (12 females) underwent a 50-m front crawl swimming time trial with minimum respiratory interruptions, following which they were categorized into two groups: Fast (n = 13) and Slow (n = 15). Additionally, they performed knee extension exercises with maximal voluntary breath- holding, wherein leg blood flow (Doppler ultrasound), cardiac output (Modelflow), heart rate (electrocardiogram), and middle cerebral artery mean blood velocity (transcranial Doppler ultrasound) were evaluated. The pattern of leg blood flow response differed between the two groups (p = 0.031) with the Fast group experiencing a delayed onset of reductions in leg blood flow (p = 0.035). The onset of bradycardia was also delayed in the Fast group (p = 0.014), with this group demonstrating a higher value of the lowest heart rate (between-trial difference in average: 15.9 [3.73, 28.2] beats/min) and cardiac output (between-trial difference in median: 2.84 L/min) (both, p ≤ 0.013). Middle cerebral artery mean blood velocity was similar between the groups (all p ≥ 0.112). We show that swimmers with superior performance in 50-m front crawl swim with limited breaths display a diminished diving reflex.

Energetics and Basic Stroke Kinematics of Swimming With Different Styles of Wetsuits.

Lim, B, Villalobos, A, Mercer, JA, and Crocker, GH. Energetics and basic stroke kinematics of swimming with different styles of wetsuits. J Strength Cond Res XX(X): 000-000, 2024-This study investigated the physiological responses and basic stroke kinematics while wearing different styles of wetsuits during submaximal intensity front-crawl swimming. Fourteen subjects (6 men and 8 women) completed a swimming-graded exercise test to determine maximal aerobic capacity (V̇O2max) and four 4-minute submaximal front-crawl swims at a pace that elicited 80% of V̇O2max with different wetsuits: regular swimsuit (no wetsuit [NWS]), buoyancy shorts (BS), sleeveless wetsuit (SLW), and full-sleeve wetsuit (FSW). The rate of oxygen consumption (V̇O2), rate of carbon dioxide production (V̇CO2), minute ventilation (V̇E), heart rate (HR), respiratory exchange ratio, and cost of swimming (CS) were determined as the average for the last minute of each trial. The rating of perceived exertion was assessed after each swimming bout. In addition, stroke length and index were determined from swimming pace and stroke rate. V̇O2, V̇CO2, V̇E, HR, and CS differed significantly among wetsuit conditions (p < 0.01). Respiratory exchange ratio and rating of perceived exertion also varied by wetsuit conditions (p < 0.05). However, stroke rate, length, and index were not significantly different across wetsuit conditions (p > 0.05). No differences existed between SLW and FSW for any dependent variable (p > 0.05). Results from this study suggest that swimming at the same pace without a wetsuit is the least economical, and both SLW and FSW are most and equally economical without significant kinematic changes. In addition, BS could be beneficial during training and racing in terms of less physiological demands than a regular swimsuit but not as economical as the SLW or FSW.

Profiling biomechanical abilities during sprint front-crawl swimming using IMU and functional clustering of variabilities

ABSTRACT This study aims to profile biomechanical abilities during sprint front crawl by identifying technical stroke characteristics, in light of performance level. Ninety-one recreational to world-class swimmers equipped with a sacrum-worn IMU performed 25 m all-out. Intra and inter-cyclic 3D kinematical variabilities were clustered using a functional double partition model. Clusters were analysed according to (1) swimming technique using continuous visualisation and discrete features (standard deviation and jerk cost) and (2) performance regarding speed and competition calibre using respectively one-way ANOVA and Chi-squared test as well as Gamma statistics. Swimmers displayed specific technical profiles of intra-cyclic (smoothy and jerky) and inter-cyclic stroke regulation (low, moderate and high repeatability) significantly discriminated by speed (p < 0.001, η2 = 0.62) and performance calibre (p < 0.001, V = 0.53). We showed that combining high levels of both kinds of variability (jerky + low repeatability) are associated with highest speed (1.86 ± 0.12 m/s) and competition calibre (ℽ = 0.75, p < 0.001). It highlights the crucial importance of variabilities combination. Technical skills might be driven by a specific alignment of stroke pattern and its associated dispersion according to the task constraints. This data-driven approach can assist eyes-based technical evaluation. Targeting the development of an explosive swimming style with a high level of body stability should be considered during training of sprinters.

The Impact of Using the Trainings of Mental Visualization on Learning Crawl Swimming

Objectives: The study aimed to investigate the impact of using mental imagery exercises in teaching crawl swimming. Methods: The experimental approach was adopted for its suitability to the nature of the study. The study sample consisted of 30 male students enrolled in the swimming course (1) for the second semester of the academic year 2020-2021 at the College of Sports Sciences, Mu'tah University. They were purposefully selected and randomly assigned to two equally matched groups. The experimental group, comprising 15 students, utilized a proposed educational program accompanied by mental imagery exercises, while the control group, also consisting of 15 students, followed a standard educational program. The implementation of the educational program lasted for 8 weeks, with two instructional sessions per week and a total of 16 instructional units. Results: There were statistically significant differences at a significance level (≥ α 0.05) in teaching crawl swimming between the two groups in dimensional measurement, in favor of the experimental group, indicating the impact of using mental imagery exercises in teaching prone crawl swimming compared to the control group. The effect size ranged from 25.31% to 15.77%. The results also showed no statistically significant differences at a significant level (≥ α 0.05) between the two groups according to the "arm movements" test. Conclusions: It is recommended to incorporate mental imagery exercises into the instructional program for teaching the front crawl swimming technique, as they have a positive impact on improving and expediting the learning process. The use of mental visualization exercises for motor skills requiring more precise motor coordination and conducting studies and scientific research on different types of swimming and more complex skills, is recommended.

The effects of sodium hydrogen carbonate ingestion during the recovery period between two 200-m front-crawl time trials

PurposeThe aim of this study was to determine how sodium hydrogen carbonate (NaHCO3) ingestion during a 1-h recovery period after a 200-m front-crawl swim affects blood–gas levels, acid–base balance, and performance during a successive trial.MethodsFourteen national-level male swimmers (age: 21 ± 3 years, body mass (BM):77 ± 10 kg, stature: 181 ± 7 cm) performed four maximal 200-m front-crawl tests. On one of the two days, the swimmers swam two 200-m tests with a 1-h recovery break, during which they drank water (WATER); on the other day, they performed the same protocol but consumed 0.3 g min−1 NaHCO3 solution during the recovery break (NaHCO3).ResultsThe ingestion of NaHCO3 before the second test had no effect on swim time despite a greater [HCO3-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${HCO}_{3}^{-}$$\\end{document}] (19.2 ± 2.3 mmol L−1) than that measured during the first test (NaHCO3) (14.5 ± 1.1 mmol L−1) and the other two tests (WATER) (12.7 ± 2.4 and 14.8 ± 1.5 mmol L−1; F = 18.554; p = 0.000) and a higher blood pH (7.46 ± 0.03) than that measured during the first test (NaHCO3) (7.39 ± 0.02) and the other two tests (WATER) (7.16 ± 0.04 and 7.20 ± 0.05); (F = 5.255; p = 0.004). An increase in blood pCO2 (0.2 ± 0.3 kPa) between both tests (NaHCO3) compared to unchanged pCO2 values (− 0.1 ± 0.3 kPa) between the other two tests (WATER) (t = − 2.984; p = 0.011; power = 0.741) was confirmed.ConclusionsNaHCO3 ingestion during the recovery period between two 200-m front-crawl time trials had a strong buffering effect that did not positively affect performance. An increase in pCO2 may have counterbalanced this impact.

2024: anticipating record-breaking performances in front crawl swimming through mathematical analysis.

Introduction: This study presented a novel approach to predict future front crawl swimming world records (WRs) by employing a methodology that integrated performance data from both running and front crawl swimming. Methods: By extracting the top one running and swimming performances from 1995 to 2023 and applying a model that correlates physiological characteristics such as maximum aerobic power, anaerobic capacity, the decrement in maximum power with prolonged effort, and performance speed and duration, it was possible to project the potential record-breaking performances in 2024 across various swimming distances for both male and female athletes. Furthermore, this approach was expected to be less susceptible to the influence of the full-body swimsuit era, which may have disrupted the typical trajectory of swimming performance progression. Results: The average relative error between the top one and estimated speeds in front crawl swimming (50-1,500m, from 1995 to 2023, and for male and female) was 0.56% ± 0.17%. For male, WR in longer distances have been predicted with new WR in the 400 and 800m. A more ambitious prediction was noted among female, with twice as many WR as among male illustrated by new WR in the 50, 200, 400 and 800m. Discussion: This study illustrated that the utilization of a prediction model based on physiological parameters yielded plausible time estimates. Additionally, the research accentuated the ongoing trajectory of surpassing existing WR into 2024, illustrating the competitive zeal fueled by an emerging framework of exceptional swimmers.

The effect of varied training methods with smaller class sizes on students' front crawl swimming skills

However, the swimming learning process sometimes generalizes these abilities. The purpose of this study was to reveal the effect of varied training methods with smaller class sizes on students' front crawl swimming skills. The research used an experiment with a one-group pre-test-post-test design. The study population was 93 students, they take swimming lessons at the Sports Education Study Program, Garut University the 2022/2023 Academic Year. The sampling technique uses purposive sampling. The sample that reached the criteria was 22 students. The research instrument used a front crawl swimming skills test. Research procedure - giving treatment with varied methods with smaller class sizes. The data analysis technique uses Paired Sample t Test. Treatment with varied lesson delivery with smaller class sizes obtained sig values. (2-tailed) of 0.000. Based on the results of the research, findings revealed the value of sig. (2-tailed) obtained is 0.000. The score was lower than 0.05, so it was concluded that the method's effect varied with smaller class sizes on students' swimming skills on the front crawling swimming skills. The conclusion of this study is that using classroom settings and methods can affect swimming skills and front crawling style.

Higher Blood Lactate with Prolongation of Underwater Section in Submaximal Front-Crawl Swimming.

The underwater phase (UP) is highly important for overall swimming performance in most swimming events. However, the metabolic effects of the prolonged UP remain unclear. The purpose of this cross-sectional study was to compare the blood lactate response to submaximal front-crawl swimming with short and extended UP. Twelve (four females) junior competitive swimmers (aged 15.4 (1.4) years) undertook 200 m front-crawl swim trials in a 25 m pool at a pre-determined "anaerobic threshold" velocity on two occasions using short (<5 m) and extended (12.5 m) UP after each turn. Pacing and total time were ensured to be identical between the trials. Capillary blood lactate response was measured. Testing for 25 m swim time with <5 m and 12.5 m UP was conducted on a separate occasion. When athletes undertook and extended UP after each propulsion from the wall, their post-exercise blood lactate concentration reached 7.9 (2.1) mmol/L, more than two times higher than the response to trial with short UP (p < 0.001). All-out 25 m swimming with <5 m or 12.5 m UP disclosed no difference in locomotion velocity (p > 0.05). In conclusion, extending UP of submaximal front-crawl swimming close to maximally allowed during the races substantially increases blood lactate accumulation, i.e., increases the reliance on anaerobic metabolism. Therefore, extended UP is most likely counterproductive for the performance in long-distance swimming, at least for the athletes with a FINA score of <800. On the other hand, the extension of UP could be an effective strategy to train 'lactate tolerance', lactate shuttling, removal, and recycling.

Advancing athlete development: How Percentile Comparison Methods (PCMs) can identify youth developmental profiles

ObjectivesInter-individual developmental differences confound the capability to accurately evaluate youth athletic performance, highlighting the need for considerate methodology and analytical approaches. The present study demonstrated how Percentile Comparison Methods (PCMs) were developed, tested, and applied to identify athlete developmental profiles in Australian youth swimming. DesignCross-sectional. MethodsParticipants were N = 866 female 100-metre (m) Front-Crawl swimmers, aged 9–15 years, competing at 36 Australian regional–national level long course events. At respective events, swim performance time was collated alongside, age, date of birth, and anthropometric measures to identify age group, relative age, and maturity status. Quadratic relative age and maturity status with 100-m performance regression trendlines were generated. Then, individual swim performances at a given relative age or maturity status were converted into percentile rank distributions and compared with raw (unadjusted) annual age-group performance percentile ranks. ResultsAt a cohort level, initial testing confirmed relative age and maturity-adjusted percentile rankings were associated with general rank improvements for relatively younger and later maturing swimmers compared to raw ranks (and vice versa). When assessing individual swimmer plots, where three percentile rank scores were compared and rank change threshold criteria applied, five Percentile Comparison Method profile types were identified, namely: ‘Early Developing’ (19 %); ‘Later Developing’ (18 %); ‘Consistent’ (15 %); ‘Mixed’ (38 %) and ‘Counteracting’ (10 %). Percentile Comparison Method plots helped identify developmentally (dis-)advantaged swimmers; specific factors leading to (dis-)advantage, and likely onward development trajectories. ConclusionsOverall and with practical considerations, Percentile Comparison Methods can improve the validity of youth athletic performance evaluation as well as inform athlete development programming.

Using Machine-Learning Technology to Implement a Nonhardware and Inexpensive Posture Detection System for Analyzing Body Posture Angles in Front Crawl Swimming

&lt;p&gt;Swimming is a sport that relies heavily on motor skills. Inability to maintain adequate bodily balance in water prevents swimmers from remaining afloat and propelling themselves. Due to the difficulty of attaching reflective stickers or LED (light-emitting diode) emitters to the body while adjusting the swimming posture, it is not possible to capture the posture like during a bicycle fitting; the refraction of water also affects the detection of the body&amp;rsquo;s posture. Addressing the shortcomings, this study developed a low-cost nonhardware posture detection system based on machine-learning models in MediaPipe. The system provides real-time and post analyses of posture angles and posture lines during front crawl swimming, thereby facilitating observation of the relationship between angle at which the arm enters the water and the body horizon. Two participants practicing front crawl were invited to test the proposed system. The experimental results confirmed that the proposed system provides effective detection and analyses of posture lines and angles in swimmers. The study also proposed the algorithm for optimizing posture angle detection to solve the problems of posture line distortion and angle calculation errors that arise when MediaPipe was used to detect a human skeleton above a water line. The system does not require the installation of hardware and is inexpensive to deploy, and it can be widely applied in front crawl swimming lessons to help learners adjust their arm&amp;rsquo;s entry angle and body horizon to reduce forward drag and increase speed.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Lower and upper extremity contributions to propulsion and resistance during semi-tethered load-velocity profiling in front crawl swimming

ABSTRACT The study estimated lower and upper extremity contributions to whole-body front crawl swimming using semi-tethered load-velocity profiling. Nine female and 11 male (inter)national-level swimmers performed 20 m semi-tethered sprints, each with five progressive loads for lower (leg kicking), upper (arm stroke), and whole-body front crawl movements. The theoretical maximal speed (v0) and load (L0), and active drag (Da) were expressed as a percentage of the sum of both extremities for the movements of each extremity to calculate their contributions. The difference of whole-body values minus the sum of both extremities was used to estimate whole-body reserves. Lower (upper) body contributions were 43.8 ± 2.8% (56.2%) for v0, 37.3 ± 7.1% (62.7%) for L0, and 39.6 ± 5.6% (60.4%) for Da. Statistically significant whole-body reserves were found for v0 (−30.9 ± 3.9%, p < 0.001) and Da (−5.7 ± 11.7%, p = 0.04). V0 reserves correlated very highly with whole-body v0 in males (r = 0.71, p = 0.014) and moderately in females (r = 0.47, p = 0.21). The lower extremities contribute substantially to front crawl load-velocity profiles of highly trained swimmers. Higher sprint swimming speeds are associated with an efficient speed transfer from lower- and upper- to whole-body movement.

The Effect of Content Knowledge on Content Development, Task Adaptations, and Children’s Task Performance in Elementary School

Purpose: We investigated the effect of a content knowledge workshop on a teacher’s content development in terms of selected task types, task adaptations, and in turn children’s task performance during a six-lesson crawl swimming unit in elementary school. Methods: One physical education teacher taught two 6-lesson units of the front crawl before (comparison) and after (experimental) the workshop to different children (n = 88). Task types, task adaptations, and task performance were collected live by trained observers. Results: The number of tasks taught increased from 48 to 61 after the workshop. Informing tasks decreased 28% (p = .005) and applying tasks increased 11% (p = .039). Task adaptations increased from 123 to 211 (p = .021). A significantly higher proportion of tasks was correctly performed by more children in the experimental group. Discussion/Conclusion: The content knowledge workshop caused a substantial shift in the teacher’s content development, which resulted in more children correctly performing the tasks.

The influence of anthropometric characteristics on swimming speed in adolescent swimmers

Swimming speed depends on anthropometric characteristics, biomechanics factors, physical fitness, physiological components, and genetics. Therefore, this study aimed to identify which anthropometric characteristics influence swimming speed in adolescent competitive swimmers. Thirty-eight male swimmers (aged 16.94 ± 0.8 years; body height: 178.3 ± 5.4 cm; body weight 67.7 ± 9.6 kg) and thirty-five female swimmers (aged 17.12 ± 0.7 years; body height: 175.1 ± 6.6 cm; body weight 59.9 ± 7.1 kg) participated in the study. All swimmers have competed at the national level in Serbia for at least three years and have at least five years of training experience. Fifteen variables were measured: arm length, hand length, leg length, foot length, seat height, wrist diameter, ankle joint diameter, elbow diameter, chest circumference, triceps skinfold, forearm skinfold, abdominal skinfold, subscapular skinfold, thigh skinfold, calf skinfold. The measurements were taken by the Martin anthropometer, Omron digital scale BF511, and John Bull caliper. Swimming speed was measured during 50-m and 100-m front crawl swimming. Multiple regression analysis revealed that arm length, wrist diameter, and chest circumference, all together, accounted for 77% of 100-m front crawl swimming speed in male swimmers, while abdominal skinfold accounted for 90% of 100-m front crawl swimming speed in female swimmers. Results showed that anthropometric characteristics could not account for adolescent swimmers' 50-m front crawl swimming speed. However, anthropometric characteristics can influence the result in swimming (100-m front crawl swimming speed) in adolescents and thus should be considered a diagnostic tool in selecting young swimmers.

Reliability of a semi-tethered front crawl sprint performance test in adolescent swimmers.

This study aimed to evaluate the test-retest reliability of a sprint performance test with semi-tethered front crawl swimming to indirectly assess the current potential to perform at maximal anaerobic effort in adolescent swimmers. Eight adolescent swimmers participated in this study (gender: females (n = 4) aged 13.0 ± 0.8 years, body height 1.6 ± 0.0m, body mass 50.1 ± 4.5kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1m, body mass 59.0 ± 8.2kg. The testing protocol consisted of two trials of 25m semi-tethered front crawl swimming with maximal effort and with 1kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15m (between 3m and 18m). The Fast Fourier Transform algorithm filtered raw instantaneous swimming velocity data in distance (time) function. A third-degree polynomial was used to extract the individual velocity profile, from which the following variables were chosen for test-retest reliability and the assessment of sprint performance: ttrial15, vmax, vmin, tvto max, tvat max, Dto vmax, Dat vmax, fatigue index. Parameters such as vmax, vmin, and ttrial15 were estimated from swimming velocity profiles and considered as reliable. The CV showed low variance <5%; while ICC2,1 demonstrated respectively good (ICC2,1: 0.88), very good (ICC2,1: 0.95), and excellent (ICC2,1: 0.98) rate of relative reliability; and the Bland-Altman index revealed an acceptable agreement (LoA ≤5%) between two measurements. The sprint performance test based on semi-tethered front crawl swimming confirmed that ttrial15, vmax, and vmin were reliable variables to indirectly indicate a potential to perform the maximal anaerobic effort among adolescent swimmers. The evaluation of the swimming velocity profiles allows coaches to monitor the adaptive changes of performance during the training process.

Agreement, reliability, predictors and classification proposal of a 15´-time trial test to assess critical power in amateur swimmers

This study aimed to explore the agreement and reliability of a 15´-time trial test (T315´) to assess critical power in a large cohort of amateur swimmers. An observational retrospective cohort study total of 2212 amateur swimmers were made evaluating the results of anthropometry, cardiovascular and functional fitness assessments. Also, the participants performed a front crawl swimming 15´all-out test to assess critical power. The Kolmogorov-Smirnov, t-test, regression, percentiles, intraclass correlation coefficient and Cohen’s d effect size were developed using a statistical software A T315´ categorization proposal was made based on sex and age. There were differences by sex in all anthropometric, functional, physiological and T315´ outcomes. The T315´ swimming test obtained almost perfect reliability in the distance based on intraclass correlation values and linear correlation coefficients. A bias of T315´ of 2% was found, which represented a total of 10.65m between tests. T315´ is a useful test to assess critical power as a baseline fitness reference value for programming swimming exercises in amateurs. Keywords: anaerobic capacity, aerobic capacity, swimming, critical speed, evaluation, assessment.

Development and Interplay of Metabolic and Mechanical Performance Determinants Over an Annual Training Period in Adolescent National-Level Squad Swimmers.

The study examined the longitudinal interplay of anthropometric, metabolic, and neuromuscular development related to performance in adolescent national-level swimmers over 12months. Seven male and 12 female swimmers (14.8 [1.3]y, FINA [International Swimming Federation] points 716 [51]) were tested before (T0) and after the preparation period (T1), at the season's peak (T2), and before the next season (T3). Anthropometric (eg, fat percentage) and neuromuscular parameters (squat and bench-press load-velocity profile) were assessed on dry land. Metabolic (cost of swimming [C], maximal oxygen uptake [V˙O2peak], and peak blood lactate [bLapeak]) and performance (sprinting speed [vsprint] and lactate thresholds [LT1 and 2]) factorswere determined using a 500-m submaximal, 200-m all-out, 20-second sprint, and incremental test (+0.03m·s-1, 3min), respectively, in front-crawl swimming. vsprint (+0.6%) and LT1 and 2 (+1.9-2.4%) increased trivially and slightly, respectively, from T0 to T2 following small to moderate strength increases (≥+10.2%) from T0 to T1 and V˙O2peak (+6.0%) from T1 to T2. Bench-press maximal strength and peak power correlated with vsprint from T0 to T2 (r ≥ .54, P < .05) and LT2 at T1 (r ≥ .47, P < .05). Changes in fat percentage and V˙O2peak (T2-T1 and T3-T2, r ≤ -.67, P < .01) and C and LT2 (T2-T0, r = -.52, P = .047) were also correlated. Increases in strength and V˙O2peak from preparation to the competition period resulted in improved sprint and endurance performance. Across the season, upper-body strength was associated with vsprint and LT2, although their changes were unrelated.

A Program for Major Taper and its Effects on Some Technical Variables and Resisting Fatigue in 100m Front Crawl Swimmers

A Program for Major Taper and its Effects on Some Technical Variables and Resisting Fatigue in 100m Front Crawl Swimmers

Stroke-Specific Swimming Critical Speed Testing: Balancing Feasibility and Scientific Rigour.

This study aimed to assess the reliability of a two-distance critical speed protocol in the specialist strokes of national-level swimmers and understand the practical feasibility of extending the protocol to increase its validity. Thirty-two national-level swimmers (butterfly n = 7; backstroke n = 8; breaststroke n = 7; front crawl n = 10) swum three 200-m and three 400-m performance trials over a three-week period. Critical speed and supra-critical speed distance capacity were computed from the linear modelling of the distance-time relationship. Swimmers were subsequently asked whether they felt they could or would want to complete an 800-m trial as part of a three-distance critical speed protocol to enhance validity. Both 200-m and 400-m performances (coefficient of variation of < 2%) and derived critical speed (typical error of ≤ 0.04 m·s-1; coefficient of variation of < 4%) were reliable for all strokes, while supra-critical speed distance capacity (typical error from 4 to 9 m; coefficient of variation from 13 to 45%) was not reliable. Response rates to the follow-up questions were 100%. Few butterfly swimmers said they felt they could complete an 800-m performance trial (39%), with more positive responses for breaststroke (71%), backstroke (100%), and front crawl swimmers (100%). Butterfly swimmers were significantly less likely to say they could or would want to complete an 800-m trial than backstroke and front crawl swimmers (p < 0.05). Including a third distance 800-m trial to increase critical speed validity would not be acceptable to butterfly swimmers, would be challenging to breaststroke swimmers, but would be acceptable to front crawl and backstroke swimmers.