Agility plays a crucial role in ice hockey training, and it can be developed directly on the ice or by additional off-ice training. Since the effectiveness of on-ice and off-ice training on players' agility have not been previously described, the purpose of this research is to compare the effects of on-ice and off-ice agility training on skating performance. Fourteen ice hockey players performed agility training on-ice for 4 weeks and off-ice for 4 weeks in a crossover design; they were tested before the agility program, after the first month and after finishing both training programs. The players were randomly assigned into one of two groups (n = 7 in each group), either performing the on-ice training protocol first (Ice1) followed by the off-ice agility training or performing the off-ice protocol first and the on-ice training second (Ice2). The test battery included straight sprints to 6.1 m and 35 m and the S corner test, test with break, weave agility with puck test and reactive agility test. The magnitude based decision showed the effect of agility training in both groups in the weave agility (Ice1, 2.9±2.8% likely improvement; Ice2, 3.1±2.5% possible improvement) and reactive agility tests (Ice1, 3.1 ±2.5% likely improvement; Ice2, 1.7±2.1% possible improvement), where the Ice1 protocol resulted in a likely positive change and Ice2 resulted in a possible positive change. The comparison of the training effect resulted in a possibly harmful change of performance in Ice2 protocol (-0.5 ± 8.9%) compared to Ice1 protocol (-1.0 ± 5.1%). On-ice training is more effective in the development of specific types of agility in adolescent U16 players. However, there is evidence that off-ice agility have motor transfer to on-ice agility. Therefore, we recommend developing on-ice agility with additional off-ice agility training during the ice hockey season.

• Klíčová slova
• Ice hockey, agility, change of direction, physiology, sports training, training, youth,
• MeSH
• hokej fyziologie   psychologie   MeSH
• klinické křížové studie MeSH
• kondiční příprava metody   MeSH
• lidé MeSH
• mladiství MeSH
• motorické dovednosti fyziologie   MeSH
• plnění a analýza úkolů MeSH
• přenos učení (psychologie) MeSH
• sportovní výkon fyziologie   psychologie   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH

Measuring microbial abundance in glacier ice and identifying its controls is essential for a better understanding and quantification of biogeochemical processes in glacial ecosystems. However, cell enumeration of glacier ice samples is challenging due to typically low cell numbers and the presence of interfering mineral particles. We quantified for the first time the abundance of microbial cells in surface ice from geographically distinct sites on the Greenland Ice Sheet (GrIS), using three enumeration methods: epifluorescence microscopy (EFM), flow cytometry (FCM), and quantitative polymerase chain reaction (qPCR). In addition, we reviewed published data on microbial abundance in glacier ice and tested the three methods on artificial ice samples of realistic cell (10(2)-10(7) cells ml(-1)) and mineral particle (0.1-100 mg ml(-1)) concentrations, simulating a range of glacial ice types, from clean subsurface ice to surface ice to sediment-laden basal ice. We then used multivariate statistical analysis to identify factors responsible for the variation in microbial abundance on the ice sheet. EFM gave the most accurate and reproducible results of the tested methodologies, and was therefore selected as the most suitable technique for cell enumeration of ice containing dust. Cell numbers in surface ice samples, determined by EFM, ranged from ~ 2 × 10(3) to ~ 2 × 10(6) cells ml(-1) while dust concentrations ranged from 0.01 to 2 mg ml(-1). The lowest abundances were found in ice sampled from the accumulation area of the ice sheet and in samples affected by fresh snow; these samples may be considered as a reference point of the cell abundance of precipitants that are deposited on the ice sheet surface. Dust content was the most significant variable to explain the variation in the abundance data, which suggests a direct association between deposited dust particles and cells and/or by their provision of limited nutrients to microbial communities on the GrIS.

• Klíčová slova
• Greenland Ice Sheet, epifluorescence microscopy, flow cytometry, glacier ice, microbial abundance, multivariate analysis, quantitative PCR,
• Publikační typ
• časopisecké články MeSH

Ice hockey requires two levels of specific agility, involving different abilities, where the level of agility and their constraints might vary by the performance level. Therefore, this study aimed to compare the relationship level between on-ice and off-ice change of directional speed (COD) of youth hockey players at two performance levels. The study was conducted during the hockey season, including U16 elite players (n = 40) and U16 sub-elite players (n = 23). Both groups performed specific on-ice fitness tests (4-m acceleration, 30-m sprint, and 6 x 54-m tests, an on-ice Illinois agility test with and without a puck) and off-ice tests consisting of non-arm swing countermovement jumps (CMJs), broad jumps, and pull-ups. Pearson correlation showed that the acceleration performance of elite players was related to the CMJ (r = -0.46) and the broad jump (r = -0.31). Sub-elite players showed stronger dependence of the 30-m sprint on the CMJ (r = -0.77) and the broad jump (r = -0.43), the relation of pulls ups (r = -0.62) and the CMJ (r = -0.50) to the 6 x 54-m test, yet no association to acceleration. Elite players differ between off-ice and on-ice performance constraints, where their skating sprint is less related to their vertical and horizontal take-off abilities than in sub-elite players. Sub-elite players' off-ice power determines their sprint and repeated sprint performance. COD performance of elite and sub-elite players is based on different conditioning constraints.

• Klíčová slova
• condition, exercise, motor control, skills, speed, testing,
• Publikační typ
• časopisecké články MeSH

The aim of this study was to determine the effects of two different rest periods, 2 min and 3 min, between consecutive sets of a repeated sprint skating ability (RSSA) test, on the skating ability of ice hockey players. Two RSSA tests, RSSA-2 and RSSA-3, were assessed on 24 ice hockey players. In RSSA-2, six sets of 3 × 80 m sprint skating, with 2 min passive recovery between two consecutive sets was allowed. In RSSA-3, the recovery period between the sets was 3 min. Average speed, average heart rate (HRaver), peak heart rate (HRpeak), blood lactate concentration ([BLa]), and rate of perceived exertion (RPE) were measured in both RSSA-2 and RSSA-3 tests. In all the sets, except set 1, the average speed of the subjects was significantly (p < 0.05) higher in RSSA-3 than the respective set in RSSA-2. Average HR and RPE were higher in RSSA-2 than RSSA-3 in most of the sets. For any given set, no difference in HRpeak was noted between RSSA-2 and RSSA-3. Post-sprint (Set 6) [BLa] was significantly (p < 0.05) higher in RSSA-3 than RSSA-2. This study concludes that the 3 min rest period is more beneficial than the 2 min rest period, for (1) increasing skating speed and (2) reducing overall cardiac workload and perceived fatigue.

• Klíčová slova
• average heart rate, average speed, blood lactate concentration, peak heart rate, rate of perceived exertion, speed decrement,
• MeSH
• bruslení * MeSH
• hokej * MeSH
• kyselina mléčná MeSH
• lidé MeSH
• odpočinek MeSH
• srdeční frekvence MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyselina mléčná MeSH

Background/Objectives: COVID-19 poses significant physiological challenges for athletes, particularly those engaged in high-intensity intermittent sports such as ice hockey. This study aimed to evaluate the impact of SARS-CoV-2 infection-especially symptomatic cases-on aerobic and anaerobic performance in professional ice hockey players. Methods: Fifty athletes from the Polish Hockey League were assigned to three groups: control (CG, n = 13), asymptomatic COVID-19 (NSG, n = 28), and symptomatic COVID-19 with post-infection SpO2 < 90% (WSG, n = 9). Each underwent assessments at three time points-pre-preparatory period 2020/2021, post-preparatory period 2020/2021, and pre-preparatory period 2021/2022. Aerobic capacity was measured via a progressive cycle ergometer test (VO2max, VO2 at lactate threshold [VO2Lt], minute ventilation [V'E], breathing frequency [BF], and lactate clearance rate [ΔLa]), and anaerobic capacity via a 30 s Wingate test (relative mean power). Results: Compared with CG and NSG, symptomatic athletes exhibited significant post-infection declines in VO2max (48.2 ± 2.9 vs. 56.2 ± 6.2 and 54.6 ± 3.9 mL/kg/min; p = 0.006, d = 1.56 vs. CG; p < 0.024, d = 1.79 vs. NSG) and VO2Lt (p < 0.05). Relative mean power also decreased in WSG (p < 0.05). In contrast, CG and NSG improved or maintained these metrics over the same period. Symptomatic players showed elevated BF post infection (p = 0.022, d = 1.72) and reduced V'E (p = 0.035; d = 0.83), while ΔLa was markedly lower (p = 0.0004; d = 2.86). Conclusions: SARS-CoV-2 infection, particularly symptomatic cases, can significantly impair both aerobic and anaerobic capacity in elite hockey players. Targeted recovery protocols are essential for restoring performance in affected athletes.

• Klíčová slova
• COVID-19, aerobic capacity, anaerobic capacity, ice hockey,
• Publikační typ
• časopisecké články MeSH

The study aimed to determine the values of selected aerobic and anaerobic capacity variables, physical profiles, and to analyze the results of on-ice tests performed by ice-hockey players relegated to a lower league. Performance of 24 ice-hockey players competing in the top league in the 2012/2013 season was analysed to this end. In the 2013/2014 season, 14 of them still played in the top league (the control group), while 10 played in the first league (the experimental group). The study was conducted one week after the end of the playoffs in the seasons under consideration. The results revealed that only in the experimental group the analysed variables changed significantly between the seasons. In the Wingate test, significant changes were only noted in mean relative power (a decrease from 9.91 to 9.14 W/kg; p=0.045) and relative total work (a decrease from 299.17 to 277.22 J/kg; p=0.048). The ramp test indicated significantly lower power output in its final stages (364 compared with 384 W; p=0.034), as well as a significant decrease in relative VO2max (from 52.70 to 48.30 ml/min/kg). Blood lactate concentrations were recorded at the 3rd, 6th, 9th and 12th min of recovery after the ramp test. The rate of post-exercise recovery, ∆LA, recorded after the ramp test turned out to be significantly lower. The times recorded in the on-ice "6x30 m stop" test increased from 32.18 to 33.10 s (p=0.047). The study showed that playing in a lower league where games were less intensive, training sessions shorter and less frequent, had an adverse effect on the performance level of the investigated players. Lower VO2max recorded in the study participants slowed down their rates of post-exercise recovery and led to a significantly worse performance in the 6x30 m stop test, as well as lower relative power and relative total work in the Wingate test.

• Klíčová slova
• aerobic capacity, anaerobic capacity, on-ice tests, recovery, team sports,
• Publikační typ
• časopisecké články MeSH

The impact of two different passive recovery durations, two and three minutes, between sets of repeated sprint skating ability (RSSA) test on skating speed, speed decrement (Sdec), and heart rate (HR) response of ice hockey forwards (n = 12) and defensemen (n = 7) were determined. Six sets of 3 × 80 m sprint, with two-minute passive recovery between two consecutive sets, were performed in RSSA-2. A three-minute passive recovery period between two consecutive sets was allowed in RSSA-3. Skating speed, Sdec, and HR were measured in all tests. Subjects skated faster (p < 0.05) in most of the RSSA-3 sets than the corresponding set of RSSA-2. Defensemen were slower (p < 0.05) than forwards in most of the cases. The Sdec was higher in defensemen than in forwards, although the difference was significant occasionally. No difference in peak HR and minimum HR between forwards and defensemen was found. RSSA-3 is beneficial over RSSA-2 in both forwards and defensemen by increasing speed. Defensemen are slower and show early fatigability than forwards, and no difference in HR response was noted between forwards and defensemen. This study concludes that three-minute recovery is beneficial over two-minute recovery by increasing skating speed, although Sdec and HR response neither vary significantly between RSSA-2 and RSSA-3, nor between forwards and defensemen.

• Klíčová slova
• fatigue index, field test, heart rate, movement pattern, performance decrement, skating performance,
• MeSH
• bruslení * MeSH
• hokej * MeSH
• lidé MeSH
• únava MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The purpose of this study was to evaluate the effects of two different rest intervals (2 min and 3 min), between two consecutive sets of repeated sprint skating ability (RSSA) tests, on the repeated sprint ability of ice hockey Forwards and Defensemen. Two protocols of RSSA tests, RSSA-2 and RSSA-3, were completed by 16 ice hockey Forwards and 8 Defensemen. Defensemen were heavier (p < 0.05) than Forwards, although their % body fat did not differ significantly. In RSSA-2, athletes performed six sets of 3×80 m sprint skating with 2 min passive recovery between two consecutive sets. In RSSA-3, the rest interval between the sets was 3 min. Average speed, average heart rate (HRaver), blood lactate concentration ([BLa]), and the rate of perceived exertion (RPE) were measured in both RSSA-2 and RSSA-3 tests. Both Forwards and Defensemen skated faster in RSSA-3 than in the corresponding set of RSSA-2. Forwards were faster than Defensemen in both the tests, however, the difference was significant (p < 0.05) only in RSSA-2. In Forwards and Defensemen, HRaver increased gradually from set 1 through set 6 in RSSA-2 and RSSA-3. In most of the sets, RPE was higher in RSSA-2 than in RSSA-3, and Defensemen perceived higher exertion than Forwards. No difference in [BLa] was noted between Forwards and Defensemen, although players of both positions showed higher [BLa] in RSSA-3 than in RSSA-2. This study concludes that (1) Forwards skate faster than Defensemen, (2) average heart rate and [BLa] do not vary between Forwards and Defensemen, and (3) a higher perceived exertion is observed in Defensemen than Forwards during repeated sprint skating tests.

• Klíčová slova
• blood lactate concentration, heart rate, rate of perceived exertion, skating speed,
• Publikační typ
• časopisecké články MeSH

Background: Visual feedback may help elicit peak performance during different types of strength and power testing, but its effect during the anaerobic Wingate test is unexplored. Therefore, the purpose of this study was to determine the effect of visual feedback on power output during a hockey-specific intermittent Wingate test (AnWT6x6) consisting of 6 stages of 6 s intervals with a 1:1 work-to-rest ratio. Methods: Thirty elite college-aged hockey players performed the AnWT6x6 with either constant (n = 15) visual feedback during all 6 stages (CVF) or restricted (n = 15) visual feedback (RVF) where feedback was shown only during the 2nd through 5th stages. Results: In the first stage, there were moderate-to-large effect sizes for absolute peak power (PP) output and PP relative to body mass and PP relative to fat-free mass. However, the remaining stages (2⁻6) displayed small or negligible effects. Conclusions: These data indicate that visual feedback may play a role in optimizing power output in a non-fatigued state (1st stage), but likely does not play a role in the presence of extreme neuromuscular fatigue (6th stage) during Wingate testing. To achieve the highest peak power, coaches and researchers could provide visual feedback during Wingate testing, as it may positively influence performance in the early stages of testing, but does not result in residual fatigue or negatively affect performance during subsequent stages.

• Klíčová slova
• anaerobic performance, elite sport, intermittent load, peak power,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Use of surgery for the treatment of infective endocarditis (IE) as related to surgical indications and operative risk for mortality has not been well defined. METHODS AND RESULTS: The International Collaboration on Endocarditis-PLUS (ICE-PLUS) is a prospective cohort of consecutively enrolled patients with definite IE from 29 centers in 16 countries. We included patients from ICE-PLUS with definite left-sided, non-cardiac device-related IE who were enrolled between September 1, 2008, and December 31, 2012. A total of 1296 patients with left-sided IE were included. Surgical treatment was performed in 57% of the overall cohort and in 76% of patients with a surgical indication. Reasons for nonsurgical treatment included poor prognosis (33.7%), hemodynamic instability (19.8%), death before surgery (23.3%), stroke (22.7%), and sepsis (21%). Among patients with a surgical indication, surgical treatment was independently associated with the presence of severe aortic regurgitation, abscess, embolization before surgical treatment, and transfer from an outside hospital. Variables associated with nonsurgical treatment were a history of moderate/severe liver disease, stroke before surgical decision, and Staphyloccus aureus etiology. The integration of surgical indication, Society of Thoracic Surgeons IE score, and use of surgery was associated with 6-month survival in IE. CONCLUSIONS: Surgical decision making in IE is largely consistent with established guidelines, although nearly one quarter of patients with surgical indications do not undergo surgery. Operative risk assessment by Society of Thoracic Surgeons IE score provides prognostic information for survival beyond the operative period. S aureus IE was significantly associated with nonsurgical management.

• Klíčová slova
• endocarditis, infection, mortality, surgery, valve,
• MeSH
• absces epidemiologie   MeSH
• antiinfekční látky terapeutické užití   MeSH
• bakteriemie farmakoterapie   epidemiologie   MeSH
• chirurgická náhrada chlopně statistika a číselné údaje   MeSH
• embolie etiologie   MeSH
• endokarditida farmakoterapie   mortalita   chirurgie   MeSH
• hodnocení rizik MeSH
• infekce spojené se zdravotní péčí farmakoterapie   mortalita   chirurgie   MeSH
• Kaplanův-Meierův odhad MeSH
• komorbidita MeSH
• lidé středního věku MeSH
• lidé MeSH
• následné studie MeSH
• pooperační komplikace epidemiologie   MeSH
• prognóza MeSH
• prospektivní studie MeSH
• senioři MeSH
• srdeční chlopně mikrobiologie   chirurgie   MeSH
• stafylokokové infekce farmakoterapie   mortalita   MeSH
• stupeň závažnosti nemoci MeSH
• teoretické modely MeSH
• výběr pacientů MeSH
• výsledek terapie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• antiinfekční látky MeSH