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Enhancing recovery is a fundamental component of high-performance sports training since it enables practitioners to potentiate physical performance and minimise the risk of injuries. Using a new sports legging embedded with an intelligent system for electrostimulation, localised heating and compression (completely embodied into the textile structures), we aimed to analyse acute recovery following a fatigue protocol. Surface electromyography- and torque-related variables were recorded on eight recreational athletes. A fatigue protocol conducted in an isokinetic dynamometer allowed us to examine isometric torque and consequent post-exercise acute recovery after using the sports legging. Regarding peak torque, no differences were found between post-fatigue and post-recovery assessments in any variable; however, pre-fatigue registered a 16% greater peak torque when compared with post-fatigue for localised heating and compression recovery methods. Our data are supported by recent meta-analyses indicating that individual recovery methods, such as localised heating, electrostimulation and compression, are not effective to recover from a fatiguing exercise. In fact, none of the recovery methods available through the sports legging tested was effective in acutely recovering the torque values produced isometrically.
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Atletas , Rendimiento Atlético , Humanos , Ejercicio Físico , Terapia por Ejercicio , FatigaRESUMEN
We aimed to compare multilayer perceptron (MLP) neural networks, radial basis function neural networks (RBF) and linear models (LM) accuracy to predict the centre of mass (CM) horizontal speed at low-moderate, heavy and severe swimming intensities using physiological and biomechanical dataset. Ten trained male swimmers completed a 7 × 200 m front crawl protocol (0.05 m.s-1 increments and 30 s intervals) to assess expiratory gases and blood lactate concentrations. Two surface and four underwater cameras recorded independent images subsequently processed focusing a three-dimensional reconstruction of two upper limb cycles at 25 and 175 m laps. Eight physiological and 13 biomechanical variables were inputted to predict CM horizontal speed. MLP, RBF and LM were implemented with the Levenberg-Marquardt algorithm (feed forward with a six-neuron hidden layer), orthogonal least squares algorithm and decomposition of matrices. MLP revealed higher prediction error than LM at low-moderate intensity (2.43 ± 1.44 and 1.67 ± 0.60%), MLP and RBF depicted lower mean absolute percentage errors than LM at heavy intensity (2.45 ± 1.61, 1.82 ± 0.92 and 3.72 ± 1.67%) and RBF neural networks registered lower errors than MLP and LM at severe intensity (2.78 ± 0.96, 3.89 ± 1.78 and 4.47 ± 2.36%). Artificial neural networks are suitable for speed model-fit at heavy and severe swimming intensities when considering physiological and biomechanical background.
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Rendimiento Atlético/fisiología , Modelos Lineales , Redes Neurales de la Computación , Natación/fisiología , Adolescente , Fenómenos Biomecánicos , Humanos , Ácido Láctico/sangre , Aprendizaje Automático , Masculino , Acondicionamiento Físico Humano , Intercambio Gaseoso Pulmonar , Estudios de Tiempo y Movimiento , Adulto JovenRESUMEN
The present study aimed to examine how high- and low-speed swimmers organise biomechanical, energetic and coordinative factors throughout extreme intensity swim. Sixteen swimmers (eight high- and eight low-speed) performed, in free condition, 100-m front crawl at maximal intensity and 25, 50 and 75-m bouts (at same pace as the previous 100-m), and 100-m maximal front crawl on the measuring active drag system (MAD-system). A 3D dual-media optoelectronic system was used to assess speed, stroke frequency, stroke length, propelling efficiency and index of coordination (IdC), with power assessed by MAD-system and energy cost by quantifying oxygen consumption plus blood lactate. Both groups presented a similar profile in speed, power output, stroke frequency, stroke length, propelling efficiency and energy cost along the effort, while a distinct coordination profile was observed (F(3, 42) = 3.59, P = 0.04). Speed, power, stroke frequency and propelling efficiency (not significant, only a tendency) were higher in high-speed swimmers, while stroke length and energy cost were similar between groups. Performing at extreme intensity led better level swimmers to achieve superior speed due to higher power and propelling efficiency, with consequent ability to swim at higher stroke frequencies. This imposes specific constraints, resulting in a distinct IdC magnitude and profile between groups.
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Rendimiento Atlético/fisiología , Destreza Motora/fisiología , Natación/fisiología , Fenómenos Biomecánicos , Metabolismo Energético/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno/fisiología , Estudios de Tiempo y Movimiento , Adulto JovenRESUMEN
To verify the metabolic responses of oxygen consumption (V[Combining Dot Above]O2), heart rate (HR), blood lactate concentrations [La], and rate of perceived exertion (RPE) when swimming at an intensity corresponding to the critical velocity (CV) assessed by a 4-parameter model (CV4par), and to check the reliability when using only a single 400-m maximal front crawl bout (T400) for CV4par assessment in age-group swimmers. Ten age-group swimmers (14-16 years old) performed 50-, 100-, 200-, 400- (T400), 800-, and 1,500-m maximal front crawl bouts to calculate CV4par. V[Combining Dot Above]O2, HR, [La], and RPE were measured immediately after bouts. Swimmers then performed 3 × 10-minute front crawl (45 seconds rest) at CV4par. V[Combining Dot Above]O2, HR, [La], and RPE were measured after 10 minutes of rest (Rest), warm-up (Pre), each 10-minute repetition, and at the end of the test (Post). CV4par was 1.33 ± 0.08 m·s. V[Combining Dot Above]O2, HR, [La], and RPE were similar between first 10-minute and Post time points in the 3 × 10-minute protocol. CV4par was equivalent to 92 ± 2% of the mean swimming speed of T400 (v400) for these swimmers. CV4par calculated through a single T400 (92%v400) showed excellent agreement (r = 0.30; 95% CI: -0.04 to 0.05 m·s, p = 0.39), low coefficient of variation (2%), and root mean square error of 0.02 ± 0.01 m·s when plotted against CV4par assessed through a 4-parameter model. These results generated the equation CV4par = 0.92 × v400. A single T400 can be used reliably to estimate the CV4par typically derived with 6 efforts in age-group swimmers.
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Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Consumo de Oxígeno/fisiología , Natación/fisiología , Adolescente , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Reproducibilidad de los ResultadosRESUMEN
This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e., dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s(-1). The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases.
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Músculo Esquelético/fisiología , Natación/fisiología , Análisis y Desempeño de Tareas , Adolescente , Fenómenos Biomecánicos , Electromiografía , Femenino , Humanos , Contracción Isométrica , Cinética , Masculino , Adulto JovenRESUMEN
The backstroke swimming start international rules changed in 2005. This study compared two backstroke start variants, both with feet parallel to each other but in complete immersion and emersion. Six elite swimmers performed two sets of 4 maximal 15 m bouts, each set using one of the variants. The starts were videotaped in the sagittal plane with two cameras, providing bi-dimensional dual-media kinematic evaluation, and an underwater force plate and a handgrip instrumented with a load cell collected kinetic data. Backstroke start with feet immerged displayed greater centre-of-mass horizontal starting position, centre-of-mass horizontal velocity at hands-off and take-off angle. Backstroke start with feet emerged showed greater wall contact time, centre-of-mass horizontal and downward vertical velocity at take-off, lower limbs horizontal impulse, and centre-of-mass downward vertical velocity during flight phase. Backstroke start with feet immerged and emerged displayed similar centre-of-mass horizontal water reach, back arc angle and 5 m starting time. Irrespective of the swimmer's feet positioning, coaches should emphasise each variant's mechanical advantages during the wall contact phases. Furthermore, the maintenance of those advantages throughout the flight should be stressed for better backstroke start performance.
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Rendimiento Atlético , Pie , Inmersión , Natación , Análisis y Desempeño de Tareas , Adulto , Dorso , Fenómenos Biomecánicos , Humanos , Cinética , Masculino , Adulto JovenRESUMEN
PURPOSE: To compare ventilatory and cardiorespiratory responses between the COSMED AquaTrainer coupled with the K4b2 and K5 wearable metabolic systems in breath-by-breath mode over a wide range of swimming speeds. METHODS: Seventeen well-trained master swimmers performed 2 front-crawl 7 × 200-m incremental intermittent protocols (increments of 0.05 m·s-1 and 30-s rest intervals, with a visual pacer) with AquaTrainer coupled with either K4b2 or K5. RESULTS: Post hoc tests showed that swimming speed was similar (mean diff.: -0.01 to 0.01 m·s-1; P = .73-.97), repeatable (intraclass correlation coefficient: .88-.99; P < .001), highly accurate, and precise (agreement; bias: -0.01 to 0.01 m·s-1; limits: -0.1 to 0.1 m·s-1) between all conditions. Ventilatory and cardiorespiratory responses were highly comparable between all conditions, despite a "small" effect size for fraction of expired carbon dioxide at the sixth 200-m step (0.5%; ηp2=.12; P = .04) and carbon dioxide production at the fifth, sixth, and seventh 200-m steps (0.3-0.5 L·min-1; ηp2=.11-.17; P = .01-.05). We also observed high accuracy, which was greater for tidal volume (0.0-0.1 L), minute ventilation (-3.7 to 5.1 L·min-1), respiratory frequency (bias: -2.1 to 1.9 breaths·min-1), and oxygen uptake (0.0-0.2 L·min-1). Bland-Altman plots showed that the distribution inside the limits of agreement and their respective 95% CIs were consistent for all ventilatory and cardiorespiratory data. The repeatability (intraclass correlation coefficient) of tidal volume (.93-.97), minute ventilation (.82-.97), respiratory frequency (.68-.96), fraction of expired carbon dioxide (.85-.95), carbon dioxide production (.77-.95), fraction of expired oxygen (.78-.92), and oxygen uptake (.94-.98) data ranged from moderate to excellent (P < .001-.05). CONCLUSIONS: Swimming with the AquaTrainer coupled with K5 (breath-by-breath mode) yields accurate, precise, and repeatable ventilatory and cardiorespiratory responses when compared with K4b2 (previous gold standard). Swimming support staff, exercise and health professionals, and researchers can now relate differences between physiological capacities measured with the AquaTrainer while coupled with either of these 2 devices.
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Natación , Dispositivos Electrónicos Vestibles , Humanos , Natación/fisiología , Dióxido de Carbono/metabolismo , Consumo de Oxígeno/fisiología , OxígenoRESUMEN
The use of massage guns has become increasingly popular in recent years. Although their use is more and more common, both in a clinical and sports context, there is still little information to guide the practitioners. This systematic review aimed to determine the effects of massage guns in healthy and unhealthy populations as pre- and post-activity or part of a treatment. Data sources used were PubMed, PEDro, Scopus, SPORTDiscus, Web of Science and Google Scholar, and the study eligibility criteria were based on "healthy and unhealthy individuals", "massage guns", "pre-activity, post-activity or part of a treatment" and "randomized and non-randomized studies" (P.I.C.O.S.). Initially, 281 records were screened, but only 11 could be included. Ten had a moderate risk of bias and one a high risk of bias. Massage guns could be effective in improving iliopsoas, hamstrings, triceps suralis and the posterior chain muscles' flexibility. In strength, balance, acceleration, agility and explosive activities, it either did not have improvements or it even showed a decrease in performance. In the recovery-related outcomes, massage guns were shown to be cost-effective instruments for stiffness reduction, range of motion and strength improvements after a fatigue protocol. No differences were found in contraction time, rating of perceived exertion or lactate concentration. Massage guns can help to improve short-term range of motion, flexibility and recovery-related outcomes, but their use in strength, balance, acceleration, agility and explosive activities is not recommended.
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INTRODUCTION: Since sex-specific accumulated oxygen deficit (AOD) during high-intensity swimming remains unstudied, this study aimed to assess AOD during 50, 100, and 200 m front-crawl performances to compare the responses between sexes and analyse the effect of lean body mass (LBM). METHODS: Twenty swimmers (16.2 ± 2.8 years, 61.6 ± 7.8 kg, and 48.8 ± 11.2 kg LBM-50% males) performed 50, 100, and 200 m to determine accumulated oxygen uptake (VÌO2Ac). The swimmers also performed an incremental test from which five submaximal steps were selected to estimate the oxygen demand (VÌO2demand) from the VÌO2 versus velocity adjustment. VÌO2 was sampled using a gas analyser coupled with a respiratory snorkel. AOD was the difference between VÌO2demand and VÌO2Ac, and LBM (i.e. lean mass not including bone mineral content) was assessed by dual-energy X-ray absorptiometry (DXA). RESULTS: A two-way ANOVA evidenced an AOD increase with distance for both sexes: 19.7 ± 2.5 versus 24.9 ± 5.5, 29.8 ± 8.0 versus 36.5 ± 5.8, and 41.5 ± 9.4 versus 5.2 ± 11.9 ml × kg-1, respectively, for 50, 100, and 200 m (with highest values for females, P < 0.01). Inverse correlations were observed between LBM and AOD for 50, 100, and 200 m (r = - 0.60, - 0.38 and - 0.49, P < 0.05). AOD values at 10 and 30 s elapsed times in each trial decreased with distance for both sexes, with values differing when female swimmers were compared to males in the 200 m trial (at 10 s: 2.6 ± 0.6 vs. 3.4 ± 0.6; and at 30 s: 7.9 ± 1.7 vs. 10.0 ± 1.8 ml × kg-1, P < 0.05). CONCLUSION: LBM differences between sexes influenced AOD values during each trial, suggesting that reduced muscle mass in female swimmers plays a role on the higher AOD (i.e. anaerobic energy) demand than males while performing supramaximal trials.
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Backstroke swimming, a cyclic and continuous movement, displays a repeating structure due to the repeated action of the limb, presenting similar (but not identical) cycles. Some variability is generated by instabilities, but this may play a functional role in the human performance, allowing individual adaptations to constraints. The current study examined the role of velocity variability in backstroke performance, hypothesizing that this variable is associated with swimmers' performance. Sixteen elite and fifteen good-level swimmers were video recorded in the sagittal plane when performing 25 m backstroke at maximal intensity in order to determine hip velocity and mean velocity, stroke rate, stroke length and indexes of coordination/synchronization. Lyapunov maximal exponent and sample entropy were also calculated for successive cycles. The elite swimmers' performances were more unstable (0.1742 ± 0.1131 versus 0.0831 ± 0.0042, p < 0.001) and complex (0.9222 ± 0.4559 versus 0.3821 ± 0.3096, p < 0.001) than their good-level counterparts, but intracycle velocity variation did not differ (11.98 ± 3.47 versus 12.03 ± 3.16%, p > 0.05). Direct relationships were observed between mean velocity and stability (r = 0.40, p = 0.03), as well as with complexity (r = 0.53, p = 0.002), with intracycle velocity variation and complexity also being related (r = 0.38, p = 0.04). Backstroke performance is associated with velocity variability, with elite swimmers being able to control it through several adaptations, overcoming the high drag and inertia.
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Natación , HumanosRESUMEN
Our aim was to analyze physiological, kinematical and performance changes induced by swimming training in regional age-group athletes. Subjects (15.7 ± 2.2 years old) performed a 4 x 50-m front-crawl test at maximal velocity (10 s rest interval) in weeks 2, 4, 9 and 12 of a 15-week macrocycle. Descriptive statistics were used and the percentage of change and smallest worthwhile change (moderate, 0.6-1.2, and large, > 1.2) were measured. Lactate concentration in the third, seventh and twelfth minute of recovery decreased significantly between weeks 2-9 (14.1, 15.7 and 17.6%) and increased between weeks 9-12 (18.2, 18.6 and 19.8%), with the HR presenting only trivial variations during the training period. Stroke length showed a large decrease in the first 50-m trial between weeks 4-9 (6.2%) and a large increase between weeks 9-12 (3.1%). The stroke rate (in all 50-m trials) increased significantly between weeks 4-9 (3- 7%) and the stroke index had a moderate to large increase in the first and third 50-m trial (3.6 and 7.1%, respectively) between weeks 9-12. The overall time decreased by 1.1% between weeks 2-12, being more evident after week 4. We concluded that physiological, kinematical and performance variables were affected by the period of training in regional age-group swimmers.
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The purpose of this study was to examine the oxygen uptake ([Formula: see text]) kinetics and the energy systems' contribution at 97.5, 100 and 102.5% of the maximal lactate steady state (MLSS) swimming intensity. Ten elite female swimmers performed three-to-five 30 min submaximal constant swimming bouts at imposed paces for the determination of the swimming velocity (v) at 100%MLSS based on a 7 x 200 m intermittent incremental protocol until voluntary exhaustion to find the v associated at the individual anaerobic threshold. [Formula: see text] kinetics (cardiodynamic, primary and slow component phases) and the aerobic and anaerobic energy contributions were assessed during the continuous exercises, which the former was studied for the beginning and second phase of exercise. Subjects showed similar time delay (TD) (mean = 11.5-14.3 s) and time constant (τp) (mean = 13.8-16.3 s) as a function of v, but reduced amplitude of the primary component for 97.5% (35.7 ± 7.3 mL.kg.min-1) compared to 100 and 102.5%MLSS (41.0 ± 7.0 and 41.3 ± 5.4 mL.kg.min-1, respectively), and τp decreased (mean = 9.6-10.8 s) during the second phase of exercise. Despite the slow component did not occur for all swimmers at all swim intensities, when observed it tended to increase as a function of v. Moreover, the total energy contribution was almost exclusively aerobic (98-99%) at 97.5, 100 and 102.5%MLSS. We suggest that well-trained endurance swimmers with a fast TD and τp values may be able to adjust faster the physiological requirements to minimize the amplitude of the slow component appearance, parameter associated with the fatigue delay and increase in exhaustion time during performance, however, these fast adjustments were not able to control the progressive fatigue occurred slightly above MLSS, and most of swimmers reached exhaustion before 30min swam.
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Lactatos/química , Oxígeno/química , Resistencia Física/fisiología , Natación , Adolescente , Umbral Anaerobio/fisiología , Atletas , Metabolismo Energético , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Humanos , Cinética , Ácido Láctico , Consumo de Oxígeno/fisiología , Factores de Tiempo , Adulto JovenRESUMEN
Our purpose was to examine the swimming biophysical responses at velocities (v) of 97.5, 100 and 102.5% of the maximal lactate steady state (MLSS). Ten elite female swimmers performed three-to-five 30-min constant tests at imposed paces to determine 97.5, 100 and 102.5%MLSS v. Gas exchange, blood lactate concentration ([La-]), stroke rate (SR) and v were determined during each test. The v values at 97.5, 100 and 102.5%MLSS were 1.21±0.07, 1.24±0.07 and 1.27±0.07m.s(-1), respectively. Oxygen uptake (VÌO2) and Pulmonary ventilation (VÌE) increased as function of v. SR and stroke length (v/SR=SL) increased as a function of v. All measured variables were constant as a function of time at 97.5%MLSS and 100%MLSS. At 102.5%MLSS SR increased (3.5%) and stroke length (SL) decreased (3.5%) as a function of time. While VÌO2 was constant at 102.5%MLSS, [La-] and VÌE increased as a function of time, suggesting hyperventilation, at v's of 97.5%MLSS and 100%MLSS swimmers completed the 30min swim in spite of decreased SL and increased SR. However, the decrease in SL and increased SF were accompanied by increased [La-] and VÌE and resulted in the inability of most swimmers to complete the 30min swim presumably due to fatigue at 102.5%MLSS.
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Ácido Láctico/sangre , Natación/fisiología , Adolescente , Adulto , Fenómenos Biofísicos/fisiología , Femenino , Humanos , Oxígeno/sangre , Intercambio Gaseoso Pulmonar/fisiología , Ventilación Pulmonar/fisiologíaRESUMEN
The variability of electromyographic (EMG) recordings between and within participants is a complex problem, rarely studied in swimming. The importance of signal normalization has long been recognized, but the method used might influence variability. The aims of this study were to: (i) assess the intra-individual variability of the EMG signal in highly skilled front crawl swimmers, (ii) determine the influence of two methods of both amplitude and time normalization of the EMG signal on intra-individual variability and of time normalization on muscle activity level and (iii) describe the muscle activity, normalized using MVIC, in relation to upper limb crawl stroke movements. Muscle activity of rectus abdominis and deltoideus medialis was recorded using wireless surface EMG in 15 adult male competitive swimmers during three trials of 12.5 m front crawl at maximal speed without breathing. Two full upper limb cycles were analyzed from each of the swimming trials, resulting in six full cycles used for the intra-individual variability assessment, quantified with the coefficient of variation (CV), coefficient of quartile variation (CQV) and the variance ratio (VR). The results of this study support previous findings on EMG patterns of deltoideus medialis and rectus abdominis as prime mover during the recovery (45% activity relative to MVIC), and stabilizer of the trunk during the pull (14.5% activity) respectively. The intra-individual variability was lower (VR of 0.34-0.47) when compared to other cyclic movements. No meaningful differences were found between variability measures CV or VR when applying either of the amplitude or the time normalization methods. In addition to reporting the mean amplitude and standard deviation, future EMG studies in swimming should also report the intra-individual variability, preferably using VR as it is independent of peak amplitude, provides a good measure of repeatability and is insensitive to mean EMG amplitude and the degree of smoothing applied.
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Electromiografía , Natación , Adolescente , Adulto , Humanos , Masculino , Músculo Esquelético/fisiología , Extremidad Superior/fisiología , Adulto JovenRESUMEN
This study assessed accuracy of surface and underwater 3D reconstruction of a calibration volume with and without homography. A calibration volume (6000 × 2000 × 2500 mm) with 236 markers (64 above and 88 underwater control points--with 8 common points at water surface--and 92 validation points) was positioned on a 25 m swimming pool and recorded with two surface and four underwater cameras. Planar homography estimation for each calibration plane was computed to perform image rectification. Direct linear transformation algorithm for 3D reconstruction was applied, using 1600000 different combinations of 32 and 44 points out of the 64 and 88 control points for surface and underwater markers (resp.). Root Mean Square (RMS) error with homography of control and validations points was lower than without it for surface and underwater cameras (P ≤ 0.03). With homography, RMS errors of control and validation points were similar between surface and underwater cameras (P ≥ 0.47). Without homography, RMS error of control points was greater for underwater than surface cameras (P ≤ 0.04) and the opposite was observed for validation points (P ≤ 0.04). It is recommended that future studies using 3D reconstruction should include homography to improve swimming movement analysis accuracy.
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Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Movimiento (Física) , Algoritmos , Fenómenos Biomecánicos , Calibración , Simulación por Computador , Recolección de Datos , Humanos , Programas Informáticos , Natación , Grabación en VideoRESUMEN
The purpose of the current study was to identify the relationships between competitive performance and tether forces according to distance swam, in the four strokes, and to analyze if relative values of force production are better determinants of swimming performance than absolute values. The subjects (n = 32) performed a 30 s tethered swimming all-out effort. The competitive swimming velocities were obtained in the distances 50, 100 and 200 m using official chronometric values of competitions within 25 days after testing protocol. Mean force and velocity (50 m event) show significant correlations for front crawl (r = .92, p < .01), backstroke (r = .81, p < .05), breaststroke (r = .94, p < .01) and butterfly (r = .92, p < .01). The data suggests that absolute values of force production are more associated to competitive performance than relative values (normalized to body mass). Tethered swimming test seems to be a reliable protocol to evaluate the swimmer stroking force production and a helpful estimator of competitive performance in short distance competitive events.
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Fuerza Muscular/fisiología , Natación/fisiología , Adolescente , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
We aimed to describe and compare the general morphological, somatotype and training background characteristics of Iberian waterpolo players (22 Portuguese and 22 Spanish National Teams players) considering their playing positions. The International Working Group of Kinanthropometry guidelines was herein followed, and a somatochart was obtained through specific software (Somatotype, Calculation and Analysis. (c)2001 SWEAT technologies). Spanish players train more hours per week (22.8 ±9.5 vs.12.2 ±5.6), are taller (187.4 cm ±6.6 vs.180.3 cm ±5.1), heavier (89.2 kg ±11.6 vs.79.1 kg ±10.0), show higher arm span (195.7 cm ±8.5 vs.185.2 cm ±7.4) and muscle mass percentage (49.0% ± 1.8 vs.46.0% ±6.0), and tend to be more mesomorphic (5.19 ±1.27 vs.4.26 ±1.32) than the Portuguese players. Concerning field positions, Spanish center forward players train more hours per week than the Portuguese (20.2 ±9.1 vs.12.2 ±3.8) and show higher arm span (204.4 cm ±7.3 vs.184.0 cm ±6.5). Spanish goal keepers and outside players show higher muscle mass percentage (49.8% ±1.5 vs.42.2% ±5.2 and 49.4% ±1.5 vs.45.5% ±4.6, respectively) than the Portuguese players. These evidences should be taken into account for the improvement of waterpolo sport...
"Comparação de indicadores morfológicos e do tempo de treino semanal em equipes de pólo aquático de diferentes níveis competitivos." O presente estudo objetivou descrever e comparar a morfologia geral, o somatótipo e horas de treino de jogadores Ibéricos de selecções nacionais de polo aquático (22 portugueses e 22 espanhóis) e compará-los quanto às posições de jogo. Utilizou-se um software específico para o desenho da somatocarta (Somatotype, Calculation and Analysis,(c)2001 SWEAT technologies). Os jogadores espanhóis, quando comparados com os portugueses, treinam mais horas por semana (22,8 ±9,5 vs.12,2 ±5,6), são mais altos (187,4 cm ±6,6 vs.180,3 cm ±5,1), mais pesados (89,2 kg ±11,6 vs.79,1 kg ±10,0), apresentam maior envergadura (195,7 cm ±8,5 vs. 185,2 cm ±7,4), percentagem de massa muscular (49,0% ±1,8 vs. 46,0% ±6,0) e tendem a ser mais mesomorfos (5,19 ±1,27 vs. 4,26 ±1,32) do que os jogadores portugueses. Quanto às posições de jogo, os pivôs espanhóis treinam mais horas por semana (20,2 ±9,1 vs.12,2 ±3,8) e apresentam maior envergadura (204,4 cm ±7,3 vs.184,0 cm ±6,5) que os portugueses. Ainda, respectivamente, os goleiros e os jogadores laterais espanhóis apresentam percentagens mais elevadas de massa muscular (49,8% ±1,5 vs.42,2% ±5,2 e 49,4% ±1,5 vs.45,5% ±4,6) do que os portugueses. Estas evidências devem ser consideradas para a melhoria do polo aquático...
"Comparación de indicadores morfológicos y de tiempo de entrenamiento semanal en equipos de waterpolo de diferentes niveles competitivos" El objetivo del estudio fue describir y comparar la morfología general, somatotipo y horas de entrenamiento de jugadores Ibéricos de selecciones nacionales de waterpolo (22 portugueses y 22 españoles) y comparar sus diferencias entre posiciones de juego. Los parámetros evaluados fueron seleccionados en la literatura. La somatocarta fue construida con un software específico (Somatotype, Calculation and Analysis, (c)2001 SWEAT technologies). Los jugadores españoles entrenan más horas por semana (22,8 ±9,5 vs.12,2 ±5,6), tienen más altura (187,4cm ± 6,6 vs.180,3 cm ±5.1), más peso (89,2 kg ±11,6 vs.79,1 kg ±10,0), más envergadura (195,7 cm ±8,5 vs. 185,2 cm ±7,4), porcentaje de masa muscular (49,0% ±1,8 vs. 46,0% ±6,0) y tienden a presentar valores más altos de mesomorfia (5,19 ±1,27 vs. 4,26 ±1,32) que los jugadores portugueses. Con respecto a las posiciones de juego, los boyas Españoles superan los portugueses en las horas de entrenamiento semanal (20,2 ±9,1 vs.12,2 ±3,8) y presentan más envergadura (204,4 cm ±7,3 vs.184,0 cm ±6,5). Los porteros y jugadores periféricos españoles tienen más masa muscular que los jugadores portugueses (49,8% ±1,5 vs. 42,2% ±5,2 e 49,4% ±1,5 vs.45,5% ±4,6), respectivamente. Estas evidencias deberán ser consideradas para la mejora del waterpolo...
Asunto(s)
Humanos , Masculino , Adulto , Rendimiento Atlético , /métodos , DeportesRESUMEN
O presente estudo visa determinar os valores de eficácia das micro situações de jogo especificas do pênalti, com ou sem posse da bola, em Polo Aquático. Complementarmente, pretende-se analisar a relação entre os valores de eficácia do pênalti e o resultado final obtido pelas equipes (vencedoras e vencidas). Foram recolhidas imagens vídeo relativas a todos encontros ocorridos no X Campeonato do Mundo de Barcelona' 2003 para a sua posterior análise. Apreciaram-se as micro situações de jogo do pênalti (com ou sem posse da bola) com base no cálculo de coeficientes de eficácia de precisão, definição, possibilidade, resolução, exatidão e concretização. No que se refere à comparação efetuada entre os valores de eficácia obtidos pelas formações vencedoras e vencidas, observou-se, na categoria masculina, diferenças nos 12 coeficientes analisados. Por seu lado, na categoria feminina, não se encontraram diferenças estatísticas. Assim, os dados obtidos, no grupo masculino, permitem confirmar a hipótese que as equipas vencedoras obtêm valores de eficácia mais elevados do que as equipas vencidas. Relativamente ao grupo feminino, a hipótese formulada não foi comprovada, levando ao entendimento de que a eficácia específica das micro situações de pênalti não se constitui como um fator determinante do resultado final.
The purpose of the present study is to assess the efficacy values specific of the penalty micro situations both with and without ball possession in water polo. Additionally, we aimed to analyze the relationship between the observed efficacy values and the condition of winner or loser. Video images were collected from all the matches of the X World Water Polo Championship (Barcelona' 2003). Subsequent analysis was performed by two experienced specialists. The appreciation of the penalty game micro situations was conducted through the determination of efficacy coefficients related to precision, definition, possibility, resolution, accuracy and concreteness. Differences between the male teams that win or lose were observed in all the 12 coefficients assessed. In the female group no statistical differences were found. In the male teams it is possible to accept the formulated hypothesis: the winning teams had higher efficacy values in the penalty micro situations comparing to the teams that were defeated. The absence of differences between the female teams seems to indicate that the efficacy in the penalty micro situation is not a strong influencing factor for the match final result.