It is known that anthropometric data (weight, height, BMI, waist circumference and WHtR) and male gender are positively correlated with greater core strength, while age is negatively correlated. For competitive athletes with no significant differences in the anthropometric data stated above, there have hardly been any studies in which isometric core strength in a seated position is quantitatively compared among athletes in different sports. This study aimed to analyse different sports in well-trained athletes using military competitive sports as an example with regard to possible differences in core strength. For this purpose, Parachuting (n=28), Military Pentathlon (n=34) and Ski Platoon (n=38) groups were compared with regard to isokinetic core strength using dynamometry in seated position. In addition to the comparison of anthropometry and isokinetic results with descriptive statistics, ANOVA and Welch-ANOVA were used to compare the means of absolute and weight-adjusted core strength. It was shown that the Ski Platoon group had significantly higher flexion peak torque values than the Military Pentathlon and Parachuting groups. Even when adjusted for weight, the values were significantly higher than those measured in the Military Pentathlon group but not significantly higher than those in the Parachuting group. For extension peak torque, it was found that the Military Pentathlon group had significantly lower values than the Ski Platoon group and, in the weight-adjusted analysis, significantly lower values than the Parachuters. Using the example of competitive military sports, this study was able to show that there are significant differences in isokinetic core strength even among professional competitive athletes.This knowledge should be used to carry out detailed quantitative analyses of core strength, even in well-trained professional athletes, to find applications for prevention or to coordinate compensating exercises.
Anthropometrische Daten (Gewicht, Körpergröße, BMI, Taillenumfang und WHtR) und das männliche Geschlecht korrelieren positiv mit der Rumpfkraft, das Alter hingegen negativ.Für Profisportler, bei denen keine signifikanten Unterschiede hinsichtlich der genannten anthropometrischen Daten vorliegen, gibt es bislang kaum Studien, die die isometrische Rumpfkraft im Sitzen in verschiedenen Sportarten untereinander quantitativ vergleichen.Ziel dieser Studie war es, bei militärischen Leistungssportlern und Soldaten mit dienstlich bedingt hoher körperlicher Beanspruchung die Rumpfkraft hinsichtlich möglicher Unterschiede zu analysieren. Hierfür wurden militärische Fallschirmsprungsportler (n=28), militärische Fünfkämpfer (n=34) und Soldaten aus einem Skizug (Skitourengeher) (n=38) hinsichtlich der im Sitzen gemessenen isokinetischen Rumpfkraft verglichen. Neben der deskriptiven Statistik und Normalverteilungsanalyse von Anthropometrie und isokinetischen Messwerten wurden die isokinetischen Messwerte sowie die gewichtsadaptierten isokinetischen Messwerte der verschiedenen Sportlergruppen mittels ANOVA und Welch-ANOVA auf Unterschiede untersucht.Es zeigte sich, dass die Skitourengeher signifikant größere Werte in der Flexion Peak Torque aufwiesen als die militärischen Fünfkämpfer und Fallschirmspringer. Auch gewichtsadaptiert waren die Werte signifikant größer gegenüber den Fünfkämpfern, aber nicht signifikant größer im Vergleich zu den Fallschirmspringern. Für die Extension Peak Torque zeigte sich, dass die militärischen Fünfkämpfer signifikant geringere Werte gegenüber den Skitourengehern und in der gewichtsadaptierten Analyse signifikant geringere Werte gegenüber den Fallschirmspringern aufwiesen. Diese Studie konnte zeigen, dass bei hochtrainierten Sportlern möglicherweise beanspruchungsinduziert signifikante Unterschiede in der isokinetischen Rumpfkraft auftreten.Vor diesem Hintergrund könnten sportartspezifische quantitative Analysen der isokinetischen Rumpfkraft im Spitzensport genutzt werden, um gezielte Trainingsprogramme zum Ausgleich von Defiziten mit dem Ziel der Leistungssteigerung und Prävention zu entwickeln.

Avalanche fatalities are quite rare in the Czech Republic. Due to the presence of avalanche fields in the two Czech mountains, forensic pathologists at some forensic medicine departments may encounter this specific mechanism of accidental death. The authors summarize medicolegal aspects of deaths in avalanches in the territory of the Czech Republic for the twenty-three-year period between 1993-2015. Ten avalanche fatalities were recorded during study period. The studied group consisted of nine male and one female victims. The average age of the deceased was 27.9 years. Skiers or ski-alpinists died in the avalanche in five cases (50%), climbers in two cases (20%), snowboarders in one case (10%), cross-country skiers in one case (10%) and in one case it was a fatality of child playing on a snowy hill (10%). The cause of death was suffocation in four cases (40%), blunt trauma in four cases (40%), and in the remaining two cases it was the survival of trapped persons several hours after being rescued from the avalanche in the hospital; both victims subsequently died as a result of prolonged shock (20%) due to a combination of prolonged suffocation and hypothermia. The time interval from the fall of the avalanche to the rescue of the trapped person was in the range of minutes to 3 hours. The presence of alcohol or drugs was not detected in any studied case.

UNASSIGNED: Bradycardia is more common among well-trained athletes than in the general population, but the association with pacemaker implantations is less known. We investigated associations of endurance training with incidence of bradycardia and pacemaker implantations, including sex differences and long-term outcome, in a cohort of endurance trained individuals.
UNASSIGNED: All Swedish skiers who completed >1 race in the cross-country skiing event Vasaloppet between 1989 and 2011 (n=209 108) and a sample of 532 290 nonskiers were followed until first event of bradycardia, pacemaker implantation, or death, depending on end point. The Swedish National Patient Register was used to obtain diagnoses. Cox regression was used to investigate associations of number of completed races and finishing time in Vasaloppet with incidence of bradycardia and pacemaker implantations. In addition, Cox regression was used to investigate associations of pacemaker implantations with death in skiers and nonskiers.
UNASSIGNED: Male skiers had a higher incidence of bradycardia (adjusted hazard ratio [aHR], 1.19 [95% CI, 1.05-1.34]) and pacemaker implantations (aHR, 1.17 [95% CI, 1.04-1.31]) compared with male nonskiers. Those who completed the most races and had the best performances exhibited the highest incidence. For female skiers in Vasaloppet, the incidence of bradycardia (aHR, 0.98 [95% CI, 0.75-1.30]) and pacemaker implantations (aHR, 0.98 [95% CI, 0.75-1.29]) was not different from that of female nonskiers. The indication for pacemaker differed between skiers and nonskiers, with sick sinus syndrome more common in the former and third-degree atrioventricular block in the latter. Skiers had lower overall mortality rates than nonskiers (aHR, 0.16 [95% CI, 0.15-0.17]). There were no differences in mortality rates by pacemaker status among skiers.
UNASSIGNED: In this study, male endurance skiers had a higher incidence of bradycardia and pacemaker implantations compared with nonskiers, a pattern not seen in women. Among male skiers, those who completed the most races and had the fastest finishing times had the highest incidence of bradycardia and pacemaker implantations. Within each group, mortality rates did not differ in relation to pacemaker status. These findings suggest that bradycardia associated with training leads to a higher risk for pacemaker implantation without a detrimental effect on mortality risk.

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OBJECTIVE: A sustained mismatch between energy intake (EI) and exercise energy expenditure (EEE) can lead to Low Energy Availability (LEA), as well as health and performance impairments characteristic of Relative Energy Deficiency in Sport (RED-S). Research in females has identified specific LEA cut-points for the risks of developing physiological and performance disturbances. Cut-points in males have yet to be evaluated; therefore, this study examined the prevalence of LEA in highly trained male cross-country skiers. The key purpose of this study was to analyze EI, resting energy expenditure (REE), EEE, and energy availability (EA) in highly trained cross-country skiers during the preparation and competition periods. The secondary objective of our study was to evaluate the relative contribution of fats and carbohydrates to EI, REE, and EEE.
METHODS: EI was determined by an estimated 24 h diet recall method, REE was assessed by indirect calorimetry, and EEE was estimated from heart rate in 27 cross-country skiers.
RESULTS: EI amounted to 4050 ± 797 kcal/day on a typical training day (TD) and 5986 ± 924 kcal/day (p < 0.001) on a typical competition day (CD). REE on TDs (2111 ± 294 kcal/day or 30 ± 6 kcal/day/kg) was higher (p < 0.05) than on CDs (1891 ± 504 kcal/day or 27 ± 7 kcal/day/kg). The EA in the athletes was <15 kcal∙kg FFM-1·d-1 on TDs and <65 kcal∙kg FFM-1·d-1 on CDs. EI was not optimal, as indicated by low EA throughout TDs (June). This could be associated with insufficient EI along with a high amount of EEE (3690.7 ± 485.2 kcal/day). During the transition from TD to CD, an increase in the contribution of fats to EI and EEE was observed in cross-country skiers.
CONCLUSIONS: The conception of LEA and REDs and their potential implication for performance is underestimated among coaches and athletes. The importance of appropriate dietary strategies is essential to ensure that enough calories are consumed to support efficient training.

The objective of this study was to test the vectorelectrocardiographic T-wave characteristics for their associations with oxygen consumption (VO2) and physical performance during a maximal cardiopulmonary exercise test (CPET) in highly trained cross-country skiers. Male highly trained cross-country skiers (n = 30) performed the maximal CPET on the bicycle ergospirometric \"Oxycon Pro\" system with simultaneous oxygen consumption (VO2) and electrocardiogram recording. The measurements were done at rest; the stage preceding anaerobic threshold (preAnT); peak load; and recovery. The anaerobic threshold was estimated by respiratory exchange ratio. Physical performance was estimated by maximal oxygen consumption (VO2max/kg). VECG characteristics were calculated using Kors transformation procedure. During the test, the magnitudes of T-vector, Tx and Ty components decreased until preAnT, then stayed relatively stable until peak load, and reversed during recovery. In univariate linear regression analysis, T-vector amplitude and Tx, Ty and Tz magnitudes were associated with VO2/kg during the test (p < 0.010). The baseline T-vector characteristics were not associated with physical performance. At the preAnT stage, Tx and T-vector amplitude were associated with VO2max/kg (RC 12.70, 95% CI 0.68-24.73, p = 0.039 and RC 10.64, 95% CI 1.62-19.67, p = 0.023, respectively).

Jumping is an important task in skiing, snowboarding, ski jumping, figure skating, volleyball and many other sports. In these examples, jumping tasks are a performance criterion, and therefore detailed insight into them is important for athletes and coaches. Therefore, this paper aims to introduce a simple and easy-to-implement jump detection algorithm for skiing using acceleration data from inertial measurement units attached to ski boots. The algorithm uses the average of the absolute vertical accelerations of the two boots. We provide results for different parameter settings of the algorithm and two types of jumps: Big Air jumps and jumps during skiing. The latter are divided into small (time of flight < 500 ms) and medium (time of flight ≥ 500 ms) jumps. The algorithm detects 100% of Big Air, 94% of medium and 44% of small jumps. In addition, the settings with the highest detection rates also have the highest number of overdetected jumps. To resolve this conflict, a penalty-adjusted score that considers the number of overdetected jumps in the final performance analysis is proposed.

The body composition monitoring using bioimpedance analysis (BIA) is important in assessing the functional state of athletes in sports. Based on changes of body composition, it is possible to optimize the actual dietary intake, as well as successfully organize the training process. The purpose of this research was to conduct a comparative assessment of BIA parameters and rest energy expenditure (REE) in highly trained cross-country skiers and young non-athletes. Material and methods. The members of the national cross-country skiing team from the Komi Republic and Russian Federation (n=30; age - 22.3±2.7 years) were examined. Practically healthy medical students served as a control group for the present study (n=40; age - 20.2±2.4 years). The participants successively passed the following study steps: assessment of the body composition by BIA (ACCUNIQ BC380), REE determination by indirect non-fasting calorimetry and calculation technique. Results. The parameters of total body water, fat-free mass, lean tissue and body cell mass were higher in contrast to the fat mass percentage in the athletes (р<0.001). The calculated REE was lower than measured REE among all the participants. At the same time, the REE calculated by the Ketch-McArdle formula significantly differed between the groups, while no differences were found between the REE calculated by the Harris-Benedict prediction equation. The measured REE were significantly higher by 16% (p<0.001) i n athletes compared to those in the control group. Conclusion. The body composition of athletes was distinguished by a significantly higher amounts of total body water, fat-free mass, skeletal muscle, active cell mass, and lower percentage of fat mass compared to healthy untrained individuals. The results obtained among athletes coincided with the idea that the magnitude of REE is determined by the mass of metabolically active tissues and to a lesser extent depends on the fat mass. BIA results can be used to monitor athletes\' body composition during the training process.

This study investigates gender differences in core muscle morphology among elite alpine skiers using ultrasonography, highlighting significant disparities that could influence training and injury prevention strategies.
METHODS: A cross-sectional design was employed, examining ultrasound imaging (USI) in 22 elite skiers (11 male, 11 female) to assess the thickness of the external oblique (EO), internal oblique (IO), transversus abdominis (TrAb), and rectus abdominis (RA) muscles.
RESULTS: Significant differences were noted, with male skiers displaying greater muscle thickness, particularly in the right IO and RA and left IO, EO, TrAb, and RA.
CONCLUSIONS: These findings suggest that male and female skiers may require different training approaches to optimize performance and reduce injury risks. This research contributes to a deeper understanding of the physical demands on elite skiers and underscores the need for gender-specific training regimens to enhance athletic outcomes and prevent injuries.

BACKGROUND: Talent transfer (TT) program is an appropriate approach to address the talent gap evident in specific sports activities, while little is known about the injury characteristics of snowboarding athletes involved in the TT program.
OBJECTIVE: To determine the epidemiology of injuries among snowboarders involved in the TT program.
METHODS: A total of 244 athletes who were not previously engaged in winter sports were selected for training in snowboarding that lasted for 109 days. The injuries and at-risk exposures (A-Es) data were recorded by physicians. Injury rates (IRs), incidence rate ratios (IRRs), and injury proportion ratios (IPRs) were calculated and compared by sex and age groups.
RESULTS: The overall and time loss (TL) IR were 32.4/1000 A-Es and 12.2/1000 A-Es respectively. The overall and non-time loss (NTL) IRR were higher for female athletes than for male athletes. Additionally, the overall IRR and TL-IRR for female athletes were higher in those athletes who aged ≤15 years old. Over 93% of TL injuries resulted in participation restriction time of ≤7 days (male athletes, 93.94%; female athletes, 94.10%). Trunk (28.43%), knee joints (21.33%), and hand/wrist (16.53%) were found as the common sites of injury in both female and male athletes. The most frequent type of injury was contusion (male athletes: 53.00%, female athletes: 59.10%) resulted from ground/apparatus contact (male athletes: 75.10%, female athletes: 75.20%).
CONCLUSIONS: The risk injury among snowboarding athletes involved in the TT program during the first snow season training was found noticeable, especially for younger female athletes. The high incidence of ground/apparatus contact-related injuries suggested the necessity of specifically designed training programs and braces for snowboarding athletes involved in the TT program.