High-level Swimmers Research Articles

Detecting urine metabolites related to training performance in swimming athletes by means of Raman spectroscopy and principal component analysis

Raman spectroscopy (RS) is a vibrational technique that is suitable for performing biochemical analyses in human tissues and fluids. This work has investigated the identification of biochemical markers due to physical performance in the urine of swimming athletes. This was achieved by means of the Raman features that were found before and after the swimming training compared to the sedentary control subjects. These particular biochemical marker identifications refer to and infer the physiological status of individuals. The urine samples (single stream) were collected before and after the training (velocity, middle distance and distance) of professional swimmers, as well as from sedentary subjects (control). The urine samples were submitted to RS (830 nm excitation, 350 mW, 400–1800 cm−1 spectral range, 4 cm−1 resolution) and the spectra after the training were compared to the spectra before training, and subsequently, to the control subjects. The principal component analysis (PCA) was employed in order to identify the biochemicals that were responsible for the spectral differences. The Raman features of the urine samples after training showed peaks that were related to common urine metabolites, such as urea and creatinine. PCA analysis also revealed Raman features that were attributed to other metabolites, such as creatine, ketone bodies, phosphate and nitrogenous compounds in the swimmers after training. RS was a rapid and reliable technique for the evaluation of urine metabolites that were related to the physical performance of high-level swimmers, which then allowed for an accurate assessment and a control of their physiological efficiencies.

Erratum: Dietary intake in high-level swimmers A 32-week prospective cohort study

Erratum: Dietary intake in high-level swimmers A 32-week prospective cohort study

Mental toughness and attributions of failure in high performing male and female swimmers

This study examined the relationship between mental toughness and failure attributions in high level swimmers. Participants were 80, (Mage=21.64, S.D: 4.96 years) regional and national level swimmers who were currently competing. Participants were asked to recall a perceived failure in the previous four weeks, fill in the controllability, stability, globality and universality attribution measure (CSGU) and eight weeks later complete the mental toughness questionnaire-48 (MTQ48). Multiple regression analysis found a significant effect of mental toughness and stability on controllability (ΔR2 = 0.042, p = 0.021) when the generalizability dimensions were added to the model. Separate multiple regression analysis for both genders, revealed that males mental toughness and stability predicted controllability (ΔR2 = 0.200, p = 0.029) compared to females mental toughness and universality (ΔR2 = 0.080, p = 0.027) predicting controllability. In conclusion the present study found evidence for mental toughness predicting controllability attributions following competitive failure for a group of high level male and female swimmers. Gender differences were found in how the generalizability attributions predicting controllability. Findings are discussed in terms of mental toughness and the generalizability dimensions predicting controllability attributions in response to competitive failure and suggestions to examine the relationship further.

Anthropometric characteristics and physiological responses of high level swimmers and performance in 100 m freestyle swimming

The effect of the anthropometric characteristics on performances has been the subject of many studies (Reilly, T., Bangsbo, J., & Franks, A. (2000). Anthropometric and physiological predispositions for elite soccer. Journal of Sports Science, 18(9), 669–683) but performance also depends on different physiological parameters. The aim of the present study is to define the anthropometric and physiological variables that best predict performance time of 100 m freestyle swimming. Twenty-five competitive male swimmers (age: 15 ± 1.2 years) participated in the research. Multiple stepwise regression analysis showed that arm span is the best predictor of 100 m freestyle swimming performance (r = 0.835). Arm span explains 68.5% of the variance of dependent variable (Adj R2: 0.685). In the final model, the variables that best describe 100 m freestyle swimming are the number of strokes of 100 m freestyle swimming, triceps skinfold, pelvis and shoulders width (Adj R2: 0.882). These findings confirm the importance of the anthropometric variables for swimming performance and could help coaches in the selection of high-level athletes.

Anthropometric characteristics and physiological responses of high level swimmers and performance in 100 m freestyle swimming

L’effet des caractéristiques anthropométriques sur les performances a fait l’objet de nombreuses études (Reilly, T., Bangsbo, J., & Franks, A. (2000). Anthropometric and physiological predispositions for elite soccer. Journal of Sports Science,18(9), 669–683) mais la performance dépend également de différents paramètres physiologiques. Le but de la présente étude est de définir les variables anthropométriques et physiologiques qui prédisent le mieux la performance au 100 m nage libre. Vingt-cinq nageurs compétitifs (âge : 15 ± 1,2 ans) ont participé à cette étude. Une analyse de régression multiple montre que l’envergure des bras est le meilleur indice prédicteur de la performance au 100 m (r = 0,835). L’envergure des bras explique 68,5 % de la variance de la variable dépendante (Adj R2 : 0,685). Dans le modèle final, les variables qui décrivent le mieux 100 m nage libre sont le nombre de coups de bras au 100 m nage libre, les plis cutanés du triceps, la largeur du pelvis et des épaules (Adj R2 : 0,882). Ces résultats confirment l’importance des variables anthropométriques dans la performance en natation et peuvent aider les entraîneurs dans la sélection des athlètes de haut niveau.

Dietary intake in high-level swimmers. A 32-week prospective cohort study

Abstract AIMS To determine whether high-level swimmers present adequate energy and macronutrient intake during each training phase of the season. METHODS A 32-week prospective cohort study was conducted with 18 elite swimmers (10 men, 20±2 years; 8 women, 20±3 years) from a competitive swimming club. This period comprised two training macrocycles, each one divided in four training phases: general, mixed, specific and competition. Dietary intake, estimated energy expenditure and daily energy requirements were assessed in every training phase. Body composition was evaluated five times throughout the season. Energy and macronutrient consumption were compared with the energy expenditure and the literature recommendations, respectively. RESULTS Athletes maintained a relatively constant dietary intake throughout the season, regardless the different needs of each training phase. The balance between energy consumption and expenditure was negative in all training phases (p=0.02; d between 1.5-6.2) for women, while men did so in half of phases (p<0.01; d between 0.3-4.1). Swimmers had higher protein intake than recommendations in 73% of the evaluations, while carbohydrate and lipids intake were lower than recommendations in 76% and 69% of the evaluations, respectively. CONCLUSION Athletes did not meet the energy demands and specific macronutrient requirements of each training phase of the competitive season.

Characteristics of sport orientation in Greek high level swimmers in relation to gender, competitive level and age

Characteristics of sport orientation in Greek high level swimmers in relation to gender, competitive level and age

Backstroke start performance: the impact of using the Omega OBL2 backstroke ledge

FINA recently approved the backstroke ledge (Omega OBL2) to improve backstroke start performance in competition, but its performance has not been thoroughly evaluated. The purpose of this study was to compare the mechanics of starts performed with and without the OBL2. Ten high-level backstroke swimmers performed three starts with, and three starts without, the OBL2. A wall-mounted force plate measured the lower limb horizontal impulse, vertical impulse, take-off velocity and take-off angle. Entry distance, time to 10 m and start of hip and knee extension were recorded using video cameras. Starts performed with the OBL2 had a 0.13 s lower time to 10 m, 2.5% less variability in time to 10 m and 0.14 m greater head entry distance. The OBL2 provides a performance advantage by allowing an increased head entry distance rather than larger horizontal impulse on the wall. This may be due to the swimmers assuming different body positions during the start manoeuvre. Additional studies are needed to evaluate factors that contribute to improved performance when using the OBL2. Swimmers should train with the OBL2 and use it in competition to ensure optimal start performance.

Changes of Swimmers' Emotional States during the Preparation of National Championship: Do Recovery-Stress States Matter?

This study examined the trajectories of emotional states and their within-person synergies with perceived stress and recovery during a 4-month training period preceding the French swimming championships. A Multilevel Growth Curve Analysis approach was used with 16 high level swimmers. Five waves of assessments of emotional states, perceived stress and recovery were completed. Results indicated that emotional states were characterized by distinct trajectories during the training period preceding a major competition. Specifically, significant positive linear effects of time (i.e., linear increase over time) and negative quadratic effects of squared time (i.e., inverted U shape over time) on anxiety, dejection and anger were observed, whereas the opposite pattern of results was found for happiness and excitement. Moreover, level 2 perceived stress and recovery (i.e., inter-individual predictors) were significantly associated with athletes’ unpleasant and pleasant emotional states respectively. At level 1, perceived recovery (i.e., intra-individual predictor) was positively associated with happiness and excitement and negatively related to anxiety, dejection and anger. Finally, within-person interactions of general stress and recovery with time and squared time reached significance for excitement, whereas within-person interactions of specific and total stress with time and squared time reached significance for anxiety. Overall, this study provided insights into the central role played by perceived stress and recovery on the emotional states experienced by high level swimmers. Operational strategies were suggested in order to optimize the stress-recovery balance and in turn the athletes’ emotional states during a complete training program.

Biophysical Determinants of Front-Crawl Swimming at Moderate and Severe Intensities.

To conduct a biophysical analysis of the factors associated with front-crawl performance at moderate and severe swimming intensities, represented by anaerobic-threshold (vAnT) and maximal-oxygen-uptake (vV̇O2max) velocities. Ten high-level swimmers performed 2 intermittent incremental tests of 7 × 200 and 12 × 25 m (through a system of underwater push-off pads) to assess vAnT, and vV̇O2max, and power output. The 1st protocol was videotaped (3D reconstruction) for kinematic analysis to assess stroke frequency (SF), stroke length (SL), propelling efficiency (ηP), and index of coordination (IdC). V̇O2 was measured and capillary blood samples (lactate concentrations) were collected, enabling computation of metabolic power. The 2nd protocol allowed calculating mechanical power and performance efficiency from the ratio of mechanical to metabolic power. Neither vAnT nor vV̇O2max was explained by SF (0.56 ± 0.06 vs 0.68 ± 0.06 Hz), SL (2.29 ± 0.21 vs 2.06 ± 0.20 m), ηP (0.38 ± 0.02 vs 0.36± 0.03), IdC (-12.14 ± 5.24 vs -9.61 ± 5.49), or metabolic-power (1063.00 ± 122.90 vs 1338.18 ± 127.40 W) variability. vV̇O2max was explained by power to overcome drag (r = .77, P ≤ .05) and ηP (r = .72, P ≤ .05), in contrast with the nonassociation between these parameters and vAnT; both velocities were well related (r = .62, P ≤ .05). The biomechanical parameters, coordination, and metabolic power seemed not to be performance discriminative at either intensity. However, the increase in power to overcome drag, for the less metabolic input, should be the focus of any intervention that aims to improve performance at severe swimming intensity. This is also true for moderate intensities, as vAnT and vV˙O2max are proportional to each other.

The Effect of an Altitude Training Camp on Swimming Start Time and Loaded Squat Jump Performance.

This study evaluated the influence of an altitude training (AT) camp on swimming start time and loaded squat jump performance. To accomplish this goal, 13 international swimmers (8 women, 5 men) were allocated to both the control (Sea Level Training, SLT) and experimental conditions (AT, 2320 m above sea level) that were separated by a one year period. All tests (15 m freestyle swimming start and loaded squat jumps with additional loads of 25%, 50%, 75%, and 100% of swimmers’ body weight) were performed before and after a concurrent 3-week strength and endurance training program prescribed by the national coach. Following the SLT camp, significant impairments in swimming start times to 10 (+3.1%) and 15 m (+4.0%) were observed (P < 0.05), whereas no significant changes for the same distances were detected following the AT camp (-0.89%; P > 0.05). Trivial changes in peak velocity were obtained during the loaded squat jump after both training periods (effect sizes: < 0.20). Based on these results we can conclude that a traditional training high—living high strategy concurrent training of 3 weeks does not adversely affect swimming start time and loaded squat jump performance in high level swimmers, but further studies are necessary to assess the effectiveness of power-oriented resistance training in the development of explosive actions.

Optimized swimmer tracking system based on a novel multi-related-targets approach

Robust tracking is a crucial step in automatic swimmer evaluation from video sequences. We designed a robust swimmer tracking system using a new multi-related-targets approach. The main idea is to consider the swimmer as a bloc of connected subtargets that advance at the same speed. If one of the subtargets is partially or totally occluded, it can be localized by knowing the position of the others. In this paper, we first introduce the two-dimensional direct linear transformation technique that we used to calibrate the videos. Then, we present the classical tracking approach based on dynamic fusion. Next, we highlight the main contribution of our work, which is the multi-related-targets tracking approach. This approach, the classical head-only approach and the ground truth are then compared, through testing on a database of high-level swimmers in training, national and international competitions (French National Championships, Limoges 2015, and World Championships, Kazan 2015). Tracking percentage and the accuracy of the instantaneous speed are evaluated and the findings show that our new appraoach is significantly more accurate than the classical approach.

Stress Biomarkers, Mood States, and Sleep during a Major Competition: “Success” and “Failure” Athlete's Profile of High-Level Swimmers

The aim of this study was to evaluate stress markers, mood states, and sleep indicators in high-level swimmers during a major 7-days competition according to the outcomes. Nine swimmers [six men and three women (age: 22 ± 2 and 22 ± 4 years, respectively)] were examined. Before (PRE) and after (POST) each race (series, semi-finals, and finals), salivary concentrations of cortisol, α-amylase (sAA), and chromogranin-A (CgA) were determined. Mood states were assessed by the profile of mood state (POMS) questionnaire completed before and after the 7-days, and self-reported sleep diaries were completed daily. In the “failure” group, cortisol and sAA significantly increased between PRE-POST measurements (p < 0.05), while sCgA was not changed. Significant overall decrease of cortisol (-52.6%) and increase of sAA (+68.7%) was shown in the “failure group.” In this group, fatigue, confusion and depression scores, and sleep duration before the finals increased. The results in the “success” group show tendencies for increased cortisol and sCgA concentrations in response to competition, while sAA was not changed. Cortisol levels before the semi-finals and finals and sCgA levels before the finals were positively correlated to the fatigue score in the “failure” group only (r = 0.89). sAA levels before and after the semi-finals were negatively correlated to sleep duration measured in the subsequent night (r = −0.90). In conclusion, the stress of the competition could trigger a negative mood profile and sleep disturbance which correspond to different responses of biomarkers related to the hypothalamo-pituitary-adrenal axis and the sympathetic nervous system (SNS) activity, cortisol, sAA, and CgA.

Using rainbow trout cell lines to further study and understand the pathogenesis of the coldwater pathogen, Flavobacterium psychrophilum

Robust tracking is a crucial step in automatic swimmer evaluation from video sequences. We designed a robust swimmer tracking system using a new multi-related-targets approach. The main idea is to consider the swimmer as a bloc of connected subtargets that advance at the same speed. If one of the subtargets is partially or totally occluded, it can be localized by knowing the position of the others. In this paper, we first introduce the two-dimensional direct linear transformation technique that we used to calibrate the videos. Then, we present the classical tracking approach based on dynamic fusion. Next, we highlight the main contribution of our work, which is the multi-related-targets tracking approach. This approach, the classical head-only approach and the ground truth are then compared, through testing on a database of high-level swimmers in training, national and international competitions (French National Championships, Limoges 2015, and World Championships, Kazan 2015). Tracking percentage and the accuracy of the instantaneous speed are evaluated and the findings show that our new appraoach is significantly more accurate than the classical approach.

A Correlational Analysis of Tethered Swimming, Swim Sprint Performance and Dry-land Power Assessments.

Swimmers are often tested on both dry-land and in swimming exercises. The aim of this study was to test the relationships between dry-land, tethered force-time curve parameters and swimming performances in distances up to 200 m. 10 young male high-level swimmers were assessed using the maximal isometric bench-press and quarter-squat, mean propulsive power in jump-squat, squat and countermovement jumps (dry-land assessments), peak force, average force, rate of force development (RFD) and impulse (tethered swimming) and swimming times. Pearson product-moment correlations were calculated among the variables. Peak force and average force were very largely correlated with the 50- and 100-m swimming performances (r=- 0.82 and -0.74, respectively). Average force was very-largely/largely correlated with the 50- and 100-m performances (r=- 0.85 and -0.67, respectively). RFD and impulse were very-largely correlated with the 50-m time (r=- 0.72 and -0.76, respectively). Tethered swimming parameters were largely correlated (r=0.65 to 0.72) with mean propulsive power in jump-squat, squat-jump and countermovement jumps. Finally, mean propulsive power in jump-squat was largely correlated (r=- 0.70) with 50-m performance. Due to the significant correlations between dry-land assessments and tethered/actual swimming, coaches are encouraged to implement strategies able to increase leg power in sprint swimmers.

Imposed Cold-water Ingestion during Open Water Swimming in Internationally Ranked Swimmers.

The authors explored the effects of open water swimming in a tropical environment on both core temperature (T c) and thermal perceptions of high-level swimmers during an official international 10-km race and two 5-km swimming tests. The swimmers drank neutral water (i. e., 28.0±3.0°C) ad libitum every 2,000 m during Competition, whereas the ingested volume was imposed in the 5-km tests: every 1,000 m, they drank 190 mL of cold water (CW, 1.1±0.7°C) or neutral water (NW, 28.0±3.0°C). They also self-rated their thermal comfort and sensation (TC and TS), and their T c was recorded. The study demonstrated that adequate fluid intake significantly decreased T c in swimmers swimming at race pace in hot water (i. e., 37.5±0.3°C vs. 38.3±0.4°C, in NW vs. Competition, respectively). This effect was more pronounced with cold water (i. e., 36.7±1.1°C, in CW). No significant changes were noted in mean heart rate (i. e., 145±5, 143±4 and 141±5 bpm for NW, CW and Competition, respectively). Further studies are needed to explore the effect of this cooling method on the performances of international swimmers during tropical swimming events.

平泳ぎキック動作中に働く非定常流体力と足部表面の圧力分布の関係

The purpose of this study was to identify the characteristics of the pressure distribution around the foot during breaststroke kicking and the relationship between the fluid force and the pressure distribution by comparison among different swimmers. Eight male elite swimmers, whose specialties were breaststroke and individual medley, participated in this study. In trials conducted in a water channel, swimmers performed breaststroke kicking for 10 seconds at individually controlled flow velocity determined in prior time trials without upper limb motion. During the trials, 8 pressure sensors were attached to the left foot to measure the pressure distribution around the foot, and the fluid forces were estimated using the procedure reported by Tsunokawa et al. (2012). To identify the relationship between the fluid force and the pressure distribution around the foot, raw pressure values and the pressure differences between the plantar side and the dorsal side were indicated. This revealed significant differences in the absolute values of pressure between the plantar and dorsal sides (p<0.01), except for the area around the fifth toe. The dorsal side pressure for high-level swimmers decreased to about −25 kN/m2, and that for slightly low-level swimmers decreased to about −12 kN/m2. These results suggest that a decrease of dorsal side pressure is closely related to an increase in the fluid force acting on the foot, and that the kicking motions of high-level swimmers create a rapid decrease of dorsal side pressure. Furthermore, unsteady vortex-like flow is closely related to an increase in the fluid force acting on the foot. Therefore, swimmers and coaches should be aware of these influences of unsteady fluid forces.

Anthropometrics related to the performance of a sample of male swimmers.

The main purpose of the present investigation of 21 elite male swimmers was to assess whether the Ape Index (the ratio between the individual's arm span and height) and/or the second-to-fourth digit length ratio (2D:4D), i.e., the ratio between the length of the second and the fourth fingers of the right hand, are associated with the performance of high-level swimmers, when mood and/or executive function are covaried. The results showed no statistically significant correlation between the Ape Index and 2D:4D ratio, performance, executive function, or mood. In contrast, statistically significant correlations were found between 2D:4D ratio and performance, executive function, and mood. Regressions indicated that 2D:4D ratio and not Ape Index is related to the performances of a sample of male swimmers.

Comparison Between Swimming VO2peak and VO2max at Different Time Intervals

Accepting that the evaluation of the aerobic energy system contribution is very important for swimming training diagnostics purposes and that oxygen uptake kinetics (VO2) is one of the most used parameters in that task, we purposed to assess the variability of the peak VO2 and VO2max values obtained in a 200 m front crawl effort, using five different presentation intervals: breath-by-breath and average of 5, 10, 15, and 20 s. Ten male high-level swimmers performed a 200 m front crawl effort at maximal velocity being attached to a respiratory valve that allowed to directly measure the breath-by-breath VO2 kinetics. VO2 peak was accepted as the highest single value on breath-by-breath sampling and VO2max was considered as the average values of the 5, 10, 15 and 20 s sampling obtained during the test. The obtained VO2peak and VO2max mean values in breath-by-breath and averaged 5 s sampling were similar to those described in the literature for experienced male competitive swimmers. Higher VO2 values were observed for breath-by-breath sampling, being observed differences between that data acquisition method and all the other time intervals (5, 10, 15 and 20 s). Differences were also visible between the 5 s averaging and the other less frequent data acquisitions considered (10, 15 and 20 s), evidencing that less frequent sampling frequencies underestimate the VO2max values. More future research about this topic, also conducted in real competition conditions, i.e., in swimming-pool (not in running or cycle ergometers) is needed.

Changes in naïve and memory T-cells in elite swimmers during a winter training season

High intensity training regimens appear to put athletes at a higher risk of illness. As these have been linked to alterations in the proportions of differentiated T cells, how training load affects these populations could have important implications for athlete susceptibility to disease. This study examined the effect of a winter training season on the proportions of circulating naïve and memory T cells subsets of high competitive level swimmers. Blood samples were taken at rest at 4 time-points during the season: before the start of the season (t0-September), after 7weeks of an initial period of gradually increasing training load (t1-November), after 6weeks of an intense training cycle (t2-February) and 48h after the main competition (t3-April) and from eleven non-athlete controls at 2 similar time-points (t2 and t3). CD4, CD8 and gamma-delta (γδ) T cells expressing the naïve (CCR7(+)CD45RA(+)), central-memory (CM-CCR7(+)CD45RA(-)), effector-memory (EM-CCR7(-)CD45RA(-)) and terminal effector (TEMRA-CCR7(-)CD45RA(+)) were quantified by flow cytometry. Statistical analyses were performed using multilevel modeling regression. Both T CD4(+) naïve and CM presented a linear increase in response to the first moment of training exposure, and had an exponential decrease until the end of the training exposure. As for TCD4(+) EM, changes were observed from t2 until the end of the training season with an exponential trend, while TCD4(+) TEMRA increased linearly throughout the season. TCD8(+) naïve increased at t1 and decreased exponentially thereafter. TCD8(+) TEMRA values decreased at t1 and increased exponentially until t3. γδT-EM had an increase at t1 and an exponential decrease afterwards. In contrast, γδT-TEMRA decreased at t1 and exponentially increased during the remaining 20weeks of training. An increase in TEMRA and EM T cells alongside a decrease in naïve T cells could leave athletes more susceptible to illness in response to variation in training stimulus during the season.