Elite Short-track Speed Skaters Research Articles

Combined proteomics and metabolomics analysis reveal the effect of a training course on the immune function of Chinese elite short-track speed skaters.

The aim of this study was to combine proteomics and metabolomics to evaluate the immune system of short-track speed skaters (STSS) before and after a training course. Our research focused on changes in urinary proteins and metabolites that have the potential to serve as indicators for training load. Urine samples were collected from 21 elite STSS (13 male and 8 female) of the China National Team before and immediately after one training course. First-beat sports sensor was used to monitor the training load. Proteomic detection was performed using a Thermo UltiMate 3000 ultra high performence chromatographynano liquid chromatograph and an Orbitrap Exploris 480 mass spectrometer. MSstats (R package) was used for the statistical evaluation of significant differences in proteins from the samples. Two filtration criteria (fold change [FC] > 2 and p < 0.05) were used to identify the differential expressed proteins. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis for differential proteins was performed to identify the pathways involved. Nontargeted metabolomic detection was performed using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS_) with an ACQUITY 2D UPLC plus Q Exactive (QE) hybrid Quadrupole-Orbitrap mass spectrometer. Differential metabolites were identified using non-parametric statistical methods (Wilcox's rank test). Two filtration criteria (FC > 1.2 and p < 0.05) were used to identify differential metabolites. Combined analysis of proteomic and metabolomics were performed on the "Wu Kong" platform. Correlation analysis was performed using Spearman's rank correlation coefficient. (1) The most upregulated proteins were immune-related proteins, including complement proteins (C9, C4-B, and C9) and immunoglobulins (IgA, IgM, and IgG). The most downregulated proteins were osteopontin (OPN) and CD44 in urine. The correlation analysis showed that the content of OPN and CD44 (the receptor for OPN) in urine were significantly negatively correlated with the upregulated immune-related proteins. The content of OPN and CD44 is sex-dependent and negatively correlated with the training load. (2) The most upregulated metabolites included lactate, cortisol, inosine, glutamine, argininosuccinate (the precursor for arginine synthesis), 3-methyl-2-oxobutyrate (the catabolite of valine), 3-methyl-2-oxovalerate (the catabolite of isoleucine), and 4-methyl-2-oxopentanoate (the catabolite of leucine), which is sex-dependent and negatively correlated with OPN and CD44. (3) The joint analysis revealed five main related pathways, including the immune and innate immune systems. The enriched immune-related proteins included complements, immunoglobulins, and protein catabolism-related proteins. The enriched immune-related metabolites included cAMP, N-acetylgalactosamine, and glutamate. (4) There is a significant negative correlation between the content of OPN and CD44 in urine and the training load. One training course can lead to the activation of the immune system and a sex-dependent decrease in the content of OPN and CD44. Training load has a significant and negative correlation with the content of OPN and CD44, suggesting that OPN and CD44 could be potential indicators for training load.

Comparative Study of Different Respiratory Muscle Training Methods: Effects on Cardiopulmonary Indices and Athletic Performance in Elite Short-Track Speedskaters.

Respiratory muscle training (RMT) improves endurance performance, balance, and ability to repeat high-intensity exercise bouts, providing a rationale to be applied in short-track speedskating. To establish a preferable RMT method for short-track speedskating, the influence of inspiratory pressure threshold loading (IPTL) and voluntary isocapnic hyperpnoea (VIH) on cardiopulmonary indices and athletic performance was investigated. Sixteen elite short-track speedskaters completed 6 weeks of RMT based on IPTL or VIH. Wingate Anaerobic Tests (WAnTs), cardiopulmonary exercise tests (CPETs), spirometry assessments, and on-ice time trials were performed before and after RMT intervention. Repeated measures ANOVA was used to assess the differences between each method's influence. No statistically significant (p > 0.05) differences between RMT methods were found in performance during the WAnT, CPET, or specific on-ice time trials. Spirometry measures were similar between both methods. Significant effects were found for the interaction between maximum breathing frequency during CPET (BFmax) and method (p = 0.009), as well as for the interaction between BFMax, method, and sex (p = 0.040). BFmax decreased for IPTL and increased for VIH. The interaction between method and sex revealed that BFmax increased only in males performing VIH. Our findings suggest that IPTL and VIH lead to analogous effects in the study participants, highlighting a negligible practical disparity in the impact of different RMT methods in elite short-track speedskaters.

Relationship Between Strength And Power In Elite Short Track Speed Skaters

PURPOSE: To examine the relationship between strength and power in elite short track speed skaters. METHODS: Ten males (mean ± SD; age 21.1 ± 1.9 y; height = 177.2 ± 5.3 cm; mass = 71.3 ± 4.8 kg) and five females (age 22.8 ± 1.3 y; height 169.1 ± 4.3 cm; mass = 60.4 ± 1.3 kg) elite short track speed skaters volunteered and consented to an IRB approved informed consent to participate. Anthropometric measurements were recorded followed by a dynamic warm-up. The athletes completed four assessments: isometric (ISOM) torque, isokinetic (ISOK) torque, vertical jump (VJ), and Wingate testing. An isokinetic dynamometer was used to assess ISOM and ISOK torque for both right and left knee extensors and flexors. For ISOK torque, participants completed one set of five repetitions at a velocity of 60°/s. ISOM assessment used a stationary 60-degree knee angle, where participants completed three repetitions for three seconds each. Peak torque for quadriceps (QUAD) and hamstrings (HAM) for both right leg (RL) and left leg (LL) were used for analysis. The VJ test was completed on an AMTI force plate, where peak power (PP) output was used for analysis. Lastly, participants conducted a Wingate anaerobic cycling test at a load of 9 g/kg of body mass, where PP output was used for analysis. SPSS 24 was used to analyze Pearson r correlations between strength and power variables. RESULTS: There was a moderately strong significant (p = 0.006) correlation (r = .669) between VJ PP and ISOK RL HAM PT. There was a moderately strong significant correlation between Wingate PP and ISOK LL QUAD PT (p = 0.004; r = .695) and ISOK RL HAM PT (p = 0.002; r = .721). There was a moderate significant correlation between Wingate PP and ISOK RL QUAD PT (p = 0.029; r = .562), ISOK LL HAM PT (p = 0.028; r = .565), and ISOM LL QUAD PT (p = 0.037; r = .542). CONCLUSIONS:Short track speed skaters train to focus on repeatable explosive movement during competition which corresponds to their lower extremity strength. During a race, short track speed skaters’ LL is in a more fixed position while the RL is isokinetically moving, which relates to our findings that the ISOM LL QUAD was correlated with PP and RL HAM and QUAD ISOK were correlated with PP. Practitioners may use this as a reference to gain insight on the benefits of training for power and strength to enhance performance.

Training load responses modelling and model generalisation in elite sports

This study aims to provide a transferable methodology in the context of sport performance modelling, with a special focus to the generalisation of models. Data were collected from seven elite Short track speed skaters over a three months training period. In order to account for training load accumulation over sessions, cumulative responses to training were modelled by impulse, serial and bi-exponential responses functions. The variable dose-response (DR) model was compared to elastic net (ENET), principal component regression (PCR) and random forest (RF) models, while using cross-validation within a time-series framework. ENET, PCR and RF models were fitted either individually (M_{I}) or on the whole group of athletes (M_{G}). Root mean square error criterion was used to assess performances of models. ENET and PCR models provided a significant greater generalisation ability than the DR model (p = 0.018, p < 0.001, p = 0.004 and p < 0.001 for ENET_{I}, ENET_{G}, PCR_{I} and PCR_{G}, respectively). Only ENET_{G} and RF_{G} were significantly more accurate in prediction than DR (p < 0.001 and p < 0.012). In conclusion, ENET achieved greater generalisation and predictive accuracy performances. Thus, building and evaluating models within a generalisation enhancing procedure is a prerequisite for any predictive modelling.

Cervical Spine and CranioVertebral region function in Elite Short Track Speed Skating Athletes

<h3>Research Objectives</h3> Previous work has suggested that neck strength and control can be a protective factor against sustaining concussions during high impacts. The objective of this study was to characterize cervical spine and craniovertebral function in elite STSS and evaluate differences by athlete biological sex and skill level. <h3>Design</h3> Cross-sectional study. <h3>Setting</h3> National and Regional High Performance Athletic Training Facilities. <h3>Participants</h3> Members of the Canadian Senior National STSS team (n=25; 48% male) as well members of the Eastern Regional STSS Development Team (n=16; 56% male) were assessed as part of their pre-season baseline physical examination. <h3>Interventions</h3> N/A. <h3>Main Outcome Measures</h3> Clinical evaluations for neck pain, cervical spine range of motion (ROM) for flexion, extension, rotation, and sideflexion; cervical strength/control and endurance for flexion, extension, and sideflexion; neck postural reactions; manual spine examination/palpation as well as craniovertebral mobility. <h3>Results</h3> Athletes presented with full ROM on clinical observation for all six cervical spine movements (median %ROM = 100). Median time for cervical flexor endurance was 46 seconds (range: 16-134s) but fibrillations were observed in 56% of participants. Extensor endurance reached the pre-determined maximum time of 180 seconds for all but 2 athletes. Performance on the craniocervical flexion test revealed a mean performance index of 65.1 (95%CI 54,5-75,7). The manual spinal exam was within normal limits for mobility, but pain was elicited in some athletes (26% right; 12% left). No differences were found between senior and junior level athletes or between males and females, except for cervical sideflexion endurance where females had significantly lower performance than males (p < 0.001). <h3>Conclusions</h3> Cervical spine and craniovertebral function did not differ by skill level in elite short track speed skaters but greater superficial muscle activation and lower than expected endurance of deep cervical flexors was identified in athletes of all levels and of both sexes. Since control of deep flexors is important for neck stability, it could be the target of specific intervention in elite short track speed skaters. <h3>Author(s) Disclosures</h3> None.

Modelling performance with exponential functions in elite short-track speed skaters

ABSTRACT Mathematical models are used to describe and predict the effects of training on performance. The initial models are structured by impulse-type transfer functions, however, cellular adaptations induced by exercise may exhibit exponential kinetics for their growth and subsequent dissipation. Accumulation of exercise bouts counteracts dissipation and progressively induces structural and functional changes leading to performance improvement. This study examined the suitability of a model with exponential terms (Exp-Model) in elite short-track speed (ST) skaters. Training loads and performance evolution from fifteen athletes (10 males, 5 females) were previously collected over a 3-month training period. Here, we computed the relationship between training loads and performance with Exp-Model and compared with previous results obtained with a variable dose-response model (Imp-Model). Exp-Model showed a higher correlation between actual and modelled performances (R2 = 0.83 ± 0.08 and 0.76 ± 0.07 for Exp-Model and Imp-Model, respectively). Concerning model parameters, a higher (time constant for growth) value was found (p = 0.0047; d = 1.4; 95% CI [0.4;1.9]) in males compared to females with Exp-model, suggesting that females have a faster adaptative response to training loads. Thus, according to this study, Exp-model may better describe training adaptations in elite ST athletes than Imp-Model.

Influence of post-exercise hot-water therapy on adaptations to training over 4 weeks in elite short-track speed skaters

Background/ObjectiveThis study aimed to investigate the effects of regular hot water bathing (HWB), undertaken 10 min after the last training session of the day, on chronic adaptations to training in elite athletes. MethodsSix short-track (ST) speed skaters completed four weeks of post-training HWB and four weeks of post-training passive recovery (PR) according to a randomized cross-over study. During HWB, participants sat in a jacuzzi (40 °C; 20 min). ResultsAccording to linear mixed models, maximal isometric strength of knee extensor muscles was significantly increased for training with HWB (p < 0.0001; d = 0.41) and a tendency (p = 0.0529) was observed concerning V˙O2max. No significant effect of training with PR or HWB was observed for several variables (p > 0.05), including aerobic peak power output, the decline rate of jump height during 1 min-continuous maximal countermovement jumps (i.e. anaerobic capacity index), and the force-velocity relationship. Regarding specific tasks on ice, a small effect of training was found on both half-lap time and total time during a 1.5-lap all-out exercise (p = 0.0487; d = 0.23 and p = 0.0332; d = 0.21, respectively) but no additional effect of HWB was observed. ConclusionIn summary, the regular HWB protocol used in this study can induce additional effects on maximal isometric strength without compromising aerobic and anaerobic adaptations or field performance in these athletes.

The Efficiency of Short Track-related Sports Injury Prevention Program on Non-contact Injury Incidence for Elite Short Track Speed Skaters

The Efficiency of Short Track-related Sports Injury Prevention Program on Non-contact Injury Incidence for Elite Short Track Speed Skaters

Unilateral Conditioning Contractions Enhance Power Output in Elite Short Track Speed Skaters.

The objective of the present study was to assess the effect of unilateral lower-body-conditioning muscle contractions during multiple sets of fatiguing repeated jumps in elite athletes. Five elite short-track speed-skating athletes performed 9 sets of 6 maximal consecutive jumps on 2 separate occasions: with (COND) and without (CTRL) preliminary voluntary conditioning contractions (CC) 5 min before the beginning of the sets. The CC consisted of 2 consecutive 3 s maximal unilateral isometric squats against a fixed bar, resulting in a 6 s overall isometric contraction per leg. For each set, power output (PO) was measured using a linear position transducer and averaged over the 6 corresponding repeated jumps. The results showed that PO was significantly greater during the test in COND than in CTRL ( p <0.01). PO significantly decreased with sets, by 19.4±4.7 and 15.2±7.6% ( p <0.001) between the first and last set in COND and CTRL, respectively. A 2×3 s maximal unilateral isometric CC, performed 5 min before unloaded repeated jumps, significantly increased mean PO. These results suggest that unilateral conditioning contractions can enhance performance in subsequent bilateral repeated jumps.

Systems model and individual simulations of training strategies in elite short-track speed skaters

ABSTRACTThis study aimed to evaluate the effect of simulated training strategies on performance potential in elite short-track speed skaters. Training load and field-based criterion performances from fifteen athletes (10 males, 5 females) were collected over a 3-month training period and the relationship between training loads and performance was computed with a variable dose-response model using a genetic algorithm. Individual simulations of tapers preceded or not preceded by an overload training (OT) were assessed. We obtained a significant correlation between actual and modelled performances (R2 = 0.76 ± 0.07). Regarding model parameters, no significant difference was found between males and females but the time to recover performance tended to be lower in females. Simulations in which the taper parameters were free highlighted that an exponential or a step taper were the most effective for increasing performance compared to a linear taper (p < 0.05). Optimal exponential taper duration after OT was 10.7 ± 2.4d and the optimal load reduction was 75.9 ± 3.7%. OT intensity had the greatest influence on the predicted performance, followed by OT duration, taper decay, and to a lesser extent load reduction during taper and taper duration. Thus, a variable dose-response systems model allows the evaluation of different taper strategies and their potential effect on performance changes.

The Effect of Preceding Race Efforts on Pacing and Short-Track Speed Skating Performance.

To examine whether preceding high-intensity race efforts in a competitive weekend affect pacing behavior and performance in elite short-track speed skaters. Finishing and intermediate lap times were gathered from 500-, 1000-, and 1500-m short-track speed skating world cups during the seasons 2011-2016. The effect of preceding races on pacing behavior and performance was explored using 2 studies. Study I: The effect of competing in extra races due to the repechage (Rep) system, leading to an increased number of high-intensity race efforts prior to the subsequent main tournament race, was explored (500-m, n = 32; 1000-m, n = 34; and 1500-m, n = 47). Study II: The performance of skaters over the tournament days was evaluated (500-m, n = 129; 1000-m, n = 54; and 1500-m, n = 114). For both analytic approaches, a 2-way repeated-measures analysis of variance was used to assess differences in pacing and performance within skaters over the races. An additional number of preceding high-intensity race efforts due to the Rep system reduced the qualification percentage in the first main tournament race for the next stage of competition in all events (500-m, direct qualification = 57.3%, Rep = 25.0%; 1000-m, direct = 44.2%, Rep = 28.3%; and 1500-m, direct = 27.1%, Rep = 18.2%) and led to a decreased pace in the initial 2 laps of the 500-m event. By contrast, tournament day (Saturday vs Sunday) only affected the pacing behavior of female skaters during the 1500-m event. High-intensity race efforts earlier in the day affected pacing and performance of elite skaters, whereas the effect of high-intensity race efforts from the previous day seemed to be only marginal.

The Impact of Different Competitive Environments on Pacing and Performance.

In real-life competitive situations, athletes are required to continuously make decisions about how and when to invest their available energy resources. This study attempted to identify how different competitive environments invite elite short-track speed skaters to modify their pacing behavior during head-to-head competition. Lap times of elite 500-, 1000- and 1500-m short-track speed skating competitions between 2011 and 2016 (N = 34,095 races) were collected. Log-transformed lap and finishing times were analyzed with mixed linear models. The fixed effects in the model were sex, season, stage of competition, start position, competition importance, event number per tournament, number of competitors per race, altitude, and time qualification. The random effects of the model were athlete identity and the residual (within-athlete race-to-race variation). Separate analyses were performed for each event. Several competitive environments, such as the number of competitors in a race (a higher number of competitors evoked most likely a faster initial pace; coefficient of variation [CV] = 1.9-9.3%), the stage of competition (likely to most likely, a slower initial pace was demonstrated in finals; CV = -1.4% to 2.0%), the possibility of time qualification (most likely a faster initial pace; CV = 2.6-5.0%), and competition importance (most likely faster races at the Olympics; CV = 1.3-3.5%), altered the pacing decisions of elite skaters in 1000- and 1500-m events. Stage of competition and start position affected 500-m pacing behavior. As demonstrated in this study, different competitive environments evoked modifications in pacing behavior, in particular in the initial phase of the race, emphasizing the importance of athlete-environment interactions, especially during head-to-head competitions.

엘리트 쇼트트랙 스피드 스케이팅 선수들의 스포츠 손상에 대한 역학 연구

The purpose of this study was to investigate sports injuries which were developed by Korean elite short track speed skaters. Seventeen elite skaters who belonged to S-City Team were enrolled in this study. The epidemiologic data were collected by an interviewer-administered questionnaire based on injury report form of the International Olympic Committee. A total of 53 injuries were reported, and 25 injuries and 28 injuries were developed in adolescents and adult skaters, respectively. In adolescent skaters, incidence rate (IR) of all injuries was 3.28 injuries/1000 athlete exposures (AEs), and the IR of the knee injuries was the highest (3.64 injuries/10000AEs). Injuries during training comprised 96% of all injuries and contact injuries were 48%. Serious injuries that needed to be absent from trains or competitions more than one day were 40% and 44% of all injures were still inducing pain with exercise. In adult skaters, total IR was 4.59 injuries/1000AEs and the highest IR was 4.13 injuries/1000AEs in knee joint. Injuries during training comprised 82.1% of all injuries and contact injuries were 53.6%. Serious injuries were 28.6% and 28.6% were still inducing pain with exercise. In conclusion, the results of this study demonstrated IRs and characteristics of sports injuries, which could be helpful to provide useful information for preparing preventive measures against the sports injuries in elite short track speed skaters.

FLUID BALANCE IN ELITE SHORT TRACK SPEED SKATERS

The aim of this study was to investigate sweat loss in elite short track speed skaters across 6 different training sessions over a three day period, and sweat sodium loss...

Regional Cerebellar Volume Reflects Static Balance in Elite Female Short-Track Speed Skaters

The cerebellum plays a critical role in balance control. Particularly, elite short-track speed skaters require fine postural control to keep a postural balance during high velocity movement across smooth ice. We investigated whether skating proficiency and gender have an effect on the volume of cerebellar subregions and static balance, using 3-dimensional magnetic resonance imaging volumetry. In addition, we further analyzed which subregions of the cerebellum correlates with the balance. The volumes of cerebellar subregions and static balance index were compared among 12 male and 11 female elite short-track speed skaters, and 11 male and 14 female healthy matched subjects. We found significant main effects of skating proficiency and gender on the volume of vermian lobule VI-VII (declive, folium, and tuber), short-track speed skaters having greater volume than control and women revealing greater volume than men. Especially, in female athletic group, the volume of vermian lobule VI-VII significantly correlates with left static balance. In addition, men showed larger skating proficiency-related differences than women in the performance of static balance. The correlation between the volume of this region and static balance in female short-track speed skaters suggests that this region would plays a critical role in balance.

Near Infrared Spectroscopy Measurements Of Muscle Metabolism In Elite Short-track Speed Skaters During On-ice Race Simulation

PURPOSE: To gain real-time information pertaining to the concentration and oxygenation changes of haemoglobin in the vastus lateralis muscle during short track race simulation, by using the wireless capabilities of a recently developed portable NIRS device. METHODS: A dual wavelength NIRS device was placed on both the right and left leg of each subject, positioned midway between the greater trachanter of the femur and the lateral epicondyl. Subjects were 6 male elite short track speed skaters, all of whom were members of the Great Britain Olympic squad (age: 22 ± 3 years, height: 172.6 ± 11.79 cm, mass: 70.75 ± 12.43 kg, mid-thigh skin fold thickness: 6.97 ± 1.3 mm). Each subject completed a race simulation for 2 Olympic race distances: 500m and 1500m. Changes in muscle oxyhaemoglobin, muscle deoxyhaemoglobin, heart rate, global oxygen consumption (VO2) and a video record were analysed for each race. RESULTS: Immediately following the start of 500m race there was an initial drop from baseline in total haemoglobin concentration as a consequence of constriction of the muscle (-5.96 ±1.6 μM). However, by the end of the race simulation, muscle haemoglobin concentration had increased significantly (+9.52 ± 8.69 μM), presumably consequent to a change in vessel diameter and blood flow. Significant differences between the right and left leg were seen at different phases of the lap. Most notably, during the 500m race, when skaters travel around the apex of the bend supported solely on the right leg ('hang' phase), the right leg shows a rapid drop in total blood haemoglobin, -6.7 ±1.06 μM, whereas the left leg shows no such drop, +2.1 ±0.6 μM. During the 1500 m athletes make less use of the hang phase, and this difference between right and left leg is not apparent. CONCLUSIONS: This is the first time that real-time NIRS measurements have been made of elite short track speeds skaters under on-ice race simulation conditions. The wireless capability of the NIRS device used allowed real-time monitoring of muscle oxygenation and blood volume. The difference in skating styles during events of different distances, reflected in changes in oxyhaemoglobin and deoxyhaemoglobin concentrations, is likely to map onto key haemodynamic (blood flow) and metabolic (oxygen consumption) parameters.