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Endurance performance is positively associated with hematological adaptations; therefore, high total hemoglobin mass and intravascular volumes are commonly observed in high-level endurance athletes. However, it is still unclear whether the fluctuations in exercise capacity that typically occur in endurance athletes during the annual training cycle are directly associated with changes in hematological adaptations, which appear to be relatively stable during this time. To better understand this issue, a study was conducted with 10 Olympic rowers, who followed the same training program. Athletes underwent laboratory testing in the competitive and the general preparation phase of an annual training cycle (a 34% reduction in training volume). This included a graded exercise test on a rowing ergometer (GXT) and blood measurements of hemoglobin concentration (Hb), total hemoglobin mass (tHb-mass), plasma volume (PV), and blood volume (BV). Decreases in maximal values of power relative to body mass (p = 0.028), lactate concentration (p = 0.005), and heart rate (p = 0.017) in the GXT were registered. At the same time, absolute (p = 0.017) and relative (p = 0.005) PV decreased. Changes in PV (rS = 0.842, p = 0.002) and BV (rS = 0.818, p = 0.004), but not in tHb-mass (rS = 0.588, p = 0.074) and Hb (rS = −0.188, p = 0.602), were significantly correlated with changes in maximal power in the GXT. Our results indicate a close relationship between changes in intravascular volumes and maximal exercise capacity after a period of reduced training loads in elite endurance athletes.

ObjectivesOxygen uptake (VO2) is one of the most important measures of fitness and critical vital sign. CPET is a valuable method of assessing fitness in sport and clinical settings. This study aimed to: (1) derive prediction models for maximal VO2(VO2max) based on exercise variables at anaerobic threshold (AT) or respiratory compensation point (RCP) or only somatic and (2) internally validate provided equations.Methods4424 male endurance athletes (EA) underwent maximal symptom-limited CPET on a treadmill (n=3330) or cycle ergometer (n=1094). The cohort was randomly divided between: variables selection (nrunners=1998; ncyclist=656), model building (nrunners=666; ncyclist=219) and validation (nrunners=666; ncyclist=219). Random Forest was used to select the most significant variables. Models were derived and internally validated with Multiple Linear Regression.ResultsRunners were 36.24±8.45 yrs.; BMI=23.94±2.43 kg·m−2; VO2max=53.81±6.67 mL·min−1·kg−1. Cyclists were 37.33±9.13 yr.; BMI=24.34±2.63 kg·m−2; VO2max=51.74±7.99 mL·min−1·kg−1. VO2at AT and RCP were the most contributing variables to exercise equations. Body mass and body fat had the highest impact on the somatic equation. Model performance for VO2maxbased on variables at AT was R2=0.81, at RCP was R2=0.91, at AT&RCP was R2=0.91 and for somatic-only was R2=0.43.ConclusionsDerived prediction models were highly accurate and fairly replicable. Formulae allow for precise estimation of VO2maxbased on submaximal exercise performance or somatic variables. Presented models are applicable for sport and clinical settling. They are a valuable supplementary method for fitness practitioners to adjust individualised training recommendations.FundingThe author(s) received no specific funding for this work.

The problem of valid and reliable research methods in paralympic sports seems of great significance, thus the aim of this study was to evaluate the validity of the Wingate test (WAnT) in assessment of anaerobic performance in elite paracanoeists competing in 200 m races. Seven paralympic athletes (32.6 ± 7.76 years), medal winners and finalists of the Paralympic Games, World and European Championships, as well as World Cups were examined. The evaluations were conducted during a competition which was held at the paralympic distance of 200 m, and included the WAnT for upper limbs and the anaerobic threshold test (ATT). Correlations of selected indices of mechanical work and power in the WAnT, as well as anaerobic threshold (AT) power, with the time recorded during the competition were used to determine indices which affected paracanoeing performance. The results indicated strong negative correlations with time achieved in the competition between peak power and total work in the WAnT, and AT power (R = -0.796 p = 0.032; R = -0.882 p = 0.009; R = -0.900 p < 0.001, respectively). The research confirmed the validity of the WAnT for the upper limbs to assess the performance level of paracanoeists. It may be concluded that the WAnT and ATT may be used for monitoring performance during the paralympic 200 m race.

The aim of this study was to compare the oxygenation response in the vastus lateralis muscle (SmO2) in two types of tests: supramaximal and maximal. Furthermore, gender differences in SmO2 response to test exercise were assessed and the usefulness of muscle oxygenation measurements in the assessment of anaerobic and aerobic capacity was determined. The Wingate test (WAnT) and the graded exercise test (GXT) to exhaustion were performed on a cycle ergometer to examine 13 female and 14 male speed skaters from the junior and U23 national teams. During both tests, SmO2 of the vastus lateralis muscle was recorded by near-infrared spectroscopy at baseline (at rest or post warm-up), at exercise, and during recovery. The most significant SmO2 indices (differences between baseline and post-exercise indices and half time for SmO2 to reach the maximal post-exercise value) were not significantly different between the tests. Gender was also not a differentiating factor in muscle oxygenation regardless of test type. In the GXT test, half time required for SmO2 to reach the maximal value correlated negatively with VO2max and test duration, thus confirming the usefulness of SmO2 measurements in the assessment of the aerobic capacity of speed skaters. In contrast, the WAnT test showed no significant correlations between exercise indices and muscle oxygenation indices. From the standpoint of the assessment of anaerobic capacity, SmO2 measurements showed little diagnostic value.

The main goal of the study was to evaluate the impact of different roller skiing techniques (classical CT and skating ST) performed under field conditions on physical capacity variables in cross-country skiers. The second purpose was to evaluate the possibility to use the test results conducted under field and laboratory conditions interchangeably to determine training loads. Eight international-level cross-country skiers (4 male, 4 female) with 8.8 ± 1.3 years of skiing experience took part in the study. The athletes performed three graded tests to exhaustion: two under field conditions (roller skiing CT and ST techniques) and one in the laboratory: treadmill running (TR). All tests were conducted within a period of two weeks to compare general and specific physical capacity outcomes. ANOVA demonstrated significant differences in the threshold heart rate (HRAT4) (ST 175.3 ± 10.8 bpm, CT 175.8 ± 10.9 bpm, TR 181.5 ± 11.1 bpm; p = 0.004), maximal oxygen uptake (VO2max) (ST 64.0 ± 4.65 ml/kg/min, CT 61.5 ± 5.09 ml/kg/min, TR 65.9 ± 2.30 ml/kg/min; p = 0.008) and maximal HR (ST 189.3 ± 10.9 bpm, CT 188.9 ± 10.6 bpm, TR 199.5 ± 10.3 bpm; p = 0.002). No significant differences were observed between classical and skating roller skiing techniques for maximal and threshold values except for threshold velocity (CT 13.4 ± 1.11 km/h vs. ST 14.7 ± 1.17 km/h p = 0.002). Maximal velocity was not measured. The main finding of the study is that it is possible to use threshold HR values obtained in roller skiing tests performed using the classical or skating techniques interchangeably to determine roller skiing training loads. The results of the study indicate that there is a need to verify maximal treadmill running exertion variables in specific roller skiing tests.

Introduction. The study sought to assess bone mineral content (BMC) and bone mineral density (BMD) in men with different levels of physical activity during the period of reaching peak bone mass Material and methods . The research included wrestlers (n = 31) and students of the University of Physical Education (n = 88) aged 18-24. The state of the bone tissue was assessed with the use of the bone densitometry (DEXA) method (lumbar spine L2-L4). Data concerning the physical activity levels and nutritional behaviours of the study participants were gathered in a diagnostic survey carried out using a specially prepared questionnaire. Results. The analysis of the results revealed that as there were no statistically significant differences in nutritional behaviours between men from particular groups, physical activity proved to be the factor which significantly differentiated the groups under investigation in terms of their bone mass. The highest mean values of the bone parameters analysed were achieved by the wrestlers, who demonstrated a high level of physical activity.

The purpose of the work was to characterize the 4-year preparation cycle for the Winter Olympic Games in Pyongyang (2018), the leading Polish speed skater M.W. Longitudinal tests included assessment of aerobic and anaerobic exercise capacity determined in laboratory tests, respectively in the graded bicycle ergometer test and in the Wingate test performed with the lower extremity. The longitudinal data from exercise tests obtained in the analyzed 4-year period of preparation for the Olympic Games clearly indicate a significant improvement in the skater's exercise capacity. In the examined period of 2015-2018, the athlete obtained an increase in VO2max value by 6.5% to the level of 55.8 ml/kg/min. The nature of the observed changes in selected exercise indicators corresponded to the assumptions and implementation of training plans. The examined athlete was very well prepared for qualifying starts in October-November 2017 and she won three Olympic qualifications at distances 500, 1000 and 1500 m. During the Olympic Games, the Polish representative started the competition with starts at distances 1500 (20th place) and 500 m (28th place). At the leading distance of 1000 m, the competitor started at her level, reaching 12th place thus fulfilling the pre-start assumptions.

Introduction . The aim of the study was to assess the influence of an 8-week endurance training program on the functional status of the respiratory muscles and breathing efficiency. Material and methods . Thirteen healthy, untrained, male students of Physical Education volunteered to participate in the study. Before and after the subjects completed the training program, they were subjected to anthropometric and spirometric measurements, and performed an incremental stress test. The spirometric measurements included maximal inspiratory pressure (PImax), active time, passive time, and diaphragm relaxation time. Measuring PImax is a simple method of evaluating the strength of the inspiratory muscles. The 8-week training program was performed on a rowing ergometer 3 times per week, using aerobic workloads. Results . The study did not confirm a significant improvement in the measured spirometric parameters following the training program. However, we observed a trend of increase in PImax values by 12 ± 21% of borderline after the training program and a significant correlation (p < 0.05) between the changes in PImax and those in VO2 max. Following the training there was also a significant reduction in the amount of body fat by 1.4 kg and an improvement of work capacity. The response of the respiratory system to exercise was also enhanced, as breathing efficiency improved (tidal volume increased in maximal exercise, while lung ventilation, the ventilatory equivalent for oxygen, and breathing frequency decreased in submaximal exercise). Conclusions . The findings of the study suggest that traditional endurance training which is implemented over a 8 weeks is not a sufficiently strong stimulus to cause a significant increase in the strength of the inspiratory muscles.

Background The aim of the study was to evaluate the effect of different kinds of respiratory muscle training (RMT) on work capacity and selected spirometric indices in trained male cross-country skiers. Methods The study involved 13 competitively trained, elite Polish male cross-country skiers. The subjects were randomly divided into two groups who completed 7 weeks of RMT: one with gradually increasing resistance (power RMT) and the other with constant resistance (endurance RMT). Both groups' training programs consisted of 30 inspiratory maneuvers performed twice a day, 6 days a week. The first week of RMT started with a low resistance (29 cmH2O). In the following weeks, resistance in the power RMT group was gradually increased, while in the endurance RMT group, inspiratory resistance was maintained at a constant level of 53 cm H2O (36±8% PImax). Maximal inspiratory pressure (PImax), peak inspiratory flow rate (PIF), and stress test indices were measured before and after RMT. The stress test was conducted on a ski ergometer, with a gradual increase in intensity in all-out effort. Results A significant increase in PImax, PIF, and exercise work capacity (test time, work output, and peak power) was noted in both groups. No significant changes were observed in the VO2max or the selected respiratory variables. Conclusions During a short training period (up to 7 weeks), the use of gradual and constant inspiratory resistance during RMT improves exercise and spirometric parameters in a similar way. RMT did not have a considerable impact on breathing efficiency in maximal effort.

The aim of the study was to evaluate the effect of maximal specific physical effort on postural balance and rifle stability in biathletes in a standing shooting position. The study included 10 junior elite biathletes. The measurements were taken with the Vicon system and AMTI force platform. Postural balance and rifle stability characteristics were determined at rest as well as 1 and 5 min post maximal specific physical effort which was performed on a ski ergometer and continued until exhaustion. Maximal physical effort exerted a significant effect on all examined postural sway and rifle sway characteristics. The duration of the post-exercise changes was longer than 5 minutes. Higher post-effort rifle sway was observed in the vertical direction than in the across the shooting line direction. Post-effort postural balance impairment in the shooting line was much greater than in the across the shooting line direction. Moreover, a strong correlation was found between postural balance and rifle stability. Maximal physical effort influenced postural balance and rifle stability during aiming. Rifle sway during aiming in a standing shooting position seems to be coordinated with the postural sway of the biathlete's body. Thus, an increase in postural sway contributes to greater sway and lesser stability of the rifle.

Enlargement of the left atrium is perceived as a part of athlete’s heart syndrome, despite the lack of evidence. So far, left atrial size has not been assessed in the context of exercise capacity. The hypothesis of the present study was that LA enlargement in athletes was physiological and fitness-related condition. In addition, we tried to assess the feasibility and normal values of left atrial strain parameters and their relationship with other signs of athlete’s heart. The study group consisted of 114 international-level rowers (17.5 ± 1.5 years old; 46.5% women). All participants underwent a cardio-pulmonary exercise test and resting transthoracic echocardiography. Beside standard echocardiographic measurements, two dimensional speckle tracking echocardiography was used to assess average peak atrial longitudinal strain, peak atrial contraction strain and early left atrial diastolic longitudinal strain. Mild, moderate and severe left atrial enlargement was present in 27.2°%, 11.4% and 4.4% athletes, respectively. There were no significant differences between subgroups with different range of left atrial enlargement in any of echocardiographic parameters of the left ventricle diastolic function, filling pressure or hypertrophy. A significant correlation was found between the left atrial volume index and maximal aerobic capacity (R > 0.3; p < 0.001). Left atrial strain parameters were independent of atrial size, left ventricle hypertrophy and left ventricle filling pressure. Decreased peak atrial longitudinal strain was observed in 4 individuals (3.5%). We concluded that LA enlargement was common in healthy, young athletes participating in endurance sport disciplines with a high level of static exertion and was strictly correlated with exercise capacity, therefore, could be perceived as another sign of athlete’s heart.

The aim of this study was to determine the relationship between the degree of cardiorespiratory fitness and the function of the right ventricle (RV). 117 rowers, age 17.5±1.5 years. All subjects underwent cardiopulmonary exercise. Standard echocardiography and 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal – RVLS-B; mid – RVLS-M, apical – RVLS-A) and global RV free-wall strain (RVLS-G) were performed. RVLS-B values were lower compared to the RVLS-M (-25.8±4.4 vs -29.3±3.5; p

The aim of the study was to evaluate the usefulness of indirect methods of assessment of VO2max for estimation of physical capacity of trained male and female rowers during a training cycle. A group of 8 female and 14 male rowers performed the maximal intensity test simulating the regatta distance (a 2 km test) and a submaximal incremental exercise test on a rowing ergometer. The suitability of the indirect methods of predicting VO2max during the training cycle was evaluated by performing the tests twice: in females at an interval of five months and in males at an interval of seven months. To indirectly estimate VO2max, regression formulas obtained for the linear relationship between the examined effort indices were utilized based on 1) mean power obtained in the 2 km test, and 2) submaximal exercises after the estimation of PWC170. Although the suitability of the two indirect methods of assessment of VO2max was statisticaly confirmed, their usefulness for estimation of changes in physical fitness of trained rowers during the training cycle was rather low. Such an opinion stems from the fact that the total error of these methods (range between 4.2-7.7% in female and 5.1-7.4% in male rowers) was higher than the real differences in VO2max values determined in direct measurements (between the first and the second examination maximal oxygen uptake rose by 3.0% in female rowers and decreased by 4.3% in male rowers).

Background: The prevalence and significance of the early repolarisation (ER) pattern in the general population has raised a number of questions. Even less data are available on athletes. Aim: To determine the prevalence and determinants of ER in a group of young high endurance athletes. Methods: We studied 117 rowers (46% women, mean age 17.5 ± 1.5 years, mean training duration 4.3 ± 1.8 years). On 12-lead electrocardiogram (ECG), we evaluated inferolateral leads for the presence of the ER pattern, defined as at least 0.1 mV elevation of the QRS-ST junction (J point) from the baseline in at least two leads. All subjects underwent detailed echocardiographic study, cardiopulmonary exercise test with evaluation of VO 2 max (mean 57.1 ± 8.4 mL/kg/min), and evaluation of complete blood count and biometric parameters (fat tissue, body mass index, body surface area). Results: We identified 35 subjects with ER in the inferior and/or lateral leads. The phenomenon was more frequent in males (n = 25, 21.36% of the overall study population) than in females (n = 10, 8.54%, p = 0.01). The training duration in both groups (with or without ER) was similar (4.4 ± 1.5 vs. 4.3 ± 1.8 years, p > 0.05). Athletes with the ER pattern had significantly higher VO 2 max (58.8 ± 7.8 vs. 55.3 ± 8.2 mL/kg/min, p = 0.03), lower resting heart rate (58.7 ± 11.3 vs. 65.4 ± 11.9 bpm, p < 0.01), higher haemoglobin level (15.2 ± 0.8 vs. 14.6 ± 1.2 g/dL, p < 0.01), higher red blood cell count (5.31 ± 0.3 vs. 4.98 ± 0.4 million/μL, p = 0.04), and lower fat tissue mass (12.1 ± 4.4 vs. 14.9 ± 6.0 kg, p < 0.01). Compared with the others, the ER group was characterised by a higher left atrial area index (12.2 ± 1.3 vs. 11.5 ± 1.6 cm 2 /m 2 , p = 0.01), right atrial area index (9.9 ± 1.3 vs. 9.0 ± 1.4 cm 2 /m 2 , p < 0.01), and right ventricular basal diameter index (2.0 ± 0.2 vs. 1.9 ± 0.2 cm/m 2 , p = 0.04). We found no significant differences in any other cardiac size and function parameters. Conclusions: ER pattern in the inferior and/or lateral leads is a frequent finding in the population of young high endurance rowers. The presence of ER pattern is associated with gender and a number of parameters reflecting the general level of fit­ness and may be considered an electrophysiological sign of the athlete’s heart. The significance of these alterations should be evaluated in prospective follow-up studies.

Introduction. The aim of the study was to assess the changes in the physical capacity of a group of leading Polish young male rowers after they completed the annual training cycle. Material and methods. The study involved 30 subjects who either belonged to the Under-23 Polish National Rowing Team or were its reserve rowers. The subjects underwent two stress tests: a maximum intensity test simulating covering the distance of a regatta (the 2 km test) and a submaximal test with a gradual increase in intensity (the anaerobic threshold test) before and after the annual training cycle. Results. Contrary to what was expected, a year of training did not cause a significant increase in the work capacity indicators measured in the study. The training programme that was implemented was found not to have been very effective in this respect. No statistically significant increase was observed in the values obtained for the subjects in the test simulating covering the distance of the race, although there was some improvement. Conclusions. Similar findings, indicating that the results of stress tests tend to remain stable, were obtained by other authors whose research involved young rowers aged approximately 20 years. However, we would still like to emphasise that the effectiveness of training which develops endurance, the basic foundation for a rower’s successful performance, should be paid more attention to in the training process.

Wstep. Ocena ukladu krązenia u mlodych sportowcow pozostaje tematem aktywnych badan. Duze trudności pojawiają sie w zakresie oceny wielkości i grubości jam serca ze wzgledu na istotne roznice antropometryczne miedzy poszczegolnymi zawodnikami gdzie trening fizyczny (nierzadko bardzo intensywny) naklada sie na okres dojrzewania i szybkiego wzrostu. Celem pracy byla ocena wplywu regularnego wysilku fizycznego na uklad krązenia u dorastających sportowcow. Material i metody. W badaniu oceniano 89 sportowcow — 41 jeden pilkarzy oraz tenisistow (grupa 1.) oraz 48 rozpoczynających kariere sportową wioślarzy (grupa 2.). U wszystkich kwalifikujących sie zawodnikow wykonano badanie ergospirometryczne z oceną szczytowego pochlaniania tlenu (VO2 max ) oraz badania elektrokardiograficzne i echokardiograficzne. Wyniki. Porownano sportowcow z obu grup, tj. pilkarzy i tenisistow (grupa 1.) z grupą wioślarzy (grupa 2.). Obie grupy nie roznily sie wiekiem (14,2 ± 1,1 v. 14,3 ± 1,2 roku; p = NS) oraz plcią (dziewczeta: 6 [7,6%] v. 8 [10,2%]; p = NS]. Dluzej trenujący pilkarze i tenisiści, w porownaniu z grupą wioślarzy, roznili sie pod wzgledem parametrow antropometrycznych, parametrow wydolności fizycznej oraz spoczynkowej czestości rytmu serca. Wiekszośc wymiarow jam serca indeksowanych wzgledem pola powierzchni ciala byla wieksza w grupie osob dluzej trenujących pilkarzy i tenisistow (koncoworozkurczowy wymiar lewej komory: 29,1 ± 2,5 v. 26,8 ± 2,7 mm/m 2 ; p < 0,001; grubośc przegrody miedzykomorowej: 6,0 ± 0,7 v. 5,4 ± 0,8 mm; p = 0,001; grubośc ściany tylnej: 0,8 ± 0,6 v. 5,2 ± 0,6; p < 0,001; proksymalny fragment drogi odplywu prawej komory: 16,1 ± 2,2 v. 14,5 ± 2,0 mm/m 2 ; p = 0,001; wymiar drogi naplywu prawej komory: 19,9 ± 2,1 v. 18,5 ± 2,6 mm/m 2 ; p = 0,01). Po zastosowaniu indeksacji allometrycznej wiekszośc oberwanych roznic przestala miec znaczenie istotne statystycznie, z wyjątkiem indeksowanej masy lewej komory (87,0 ± 13,9 v. 76,8 ± 12,2 g/(m 2 )1,5; p = 0,001). Wnioski. 1. Zastosowanie indeksacji allometrycznej w stosunku do parametrow echokardiograficznych u dorastających sportowcow wydaje sie wlaściwe ze wzgledu na nieliniową zaleznośc pomiedzy tempem wzrostu, a szybkością zwiekszania sie narządow wewnetrznych w tej grupie wiekowej. 2. Nawet krotki trening fizyczny u dorastających sportowcow ma istotny wplyw na poprawe parametrow wydolności fizycznej, bez znaczącego wplywu na wiekszośc parametrow morfologicznych serca.

Sphingosine-1-phosphate (S1P) is a bioactive lysosphingolipid that is found in relatively high concentration in human plasma. Erythrocytes, endothelial cells, and activated platelets are the main sources of circulating S1P. The majority of plasma S1P is transported bound to high-density lipoprotein (HDL) and albumin. In recent years HDL-bound S1P attracted much attention due to its cardioprotective and anti-atherogenic properties. We have previously found that endurance-trained athletes are characterized by higher plasma S1P concentration compared to untrained individuals. This finding prompted us to examine the effect of endurance training on S1P metabolism in blood. Thirteen healthy, untrained, male subjects completed 8-week training program on a rowing ergometer. Three days before the first, and three days after the last training session, blood samples were drawn from an antecubital vein. We found that total plasma S1P concentration was increased after the training. Further analysis of different plasma fractions showed that the training selectively elevated HDL-bound S1P. This effect was associated with activation of sphingosine kinase in erythrocytes and platelets, and enhanced S1P release from red blood cells. We postulate that increase in HDL-bound S1P level is one of the mechanisms underlying beneficial effects of regular physical activity on cardiovascular diseases. This article is protected by copyright. All rights reserved.

The aim of this study was to characterize changes in maximal oxygen uptake over several years and to elaborate current reference values of this index based on determinations carried out in large and representative groups of top Polish rowers. For this study 81 female and 159 male rowers from the sub-junior to senior categories were recruited from the Polish National Team and its direct backup. All the subjects performed an incremental exercise test on a rowing ergometer. During the test maximal oxygen uptake was measured with the BxB method. The calculated reference values for elite Polish junior and U23 rowers allowed to evaluate the athletes’ fitness level against the respective reference group and may aid the coach in controlling the training process. Mean values of VO2max achieved by members of the top Polish rowing crews who over the last five years competed in the Olympic Games or World Championships were also presented. The results of the research on the “trainability” of the maximal oxygen uptake may lead to a conclusion that the growth rate of the index is larger in case of high-level athletes and that the index (in absolute values) increases significantly between the age of 19-22 years (U23 category).

Introduction . The objective of the study was to determine the maximal inspiratory mouth pressure (PImax) of highly trained male and female athletes competing in endurance sports and of non-training students of both sexes. Analysis was conducted of the dependence of PImax levels on somatic indices and training experience. The reproducibility of the method for measuring PImax index was determined. Material and methods . The study examined a total of 234 training and non-training individuals (78 women and 156 men). The test subjects were measured for PImax, as well as inspiratory time, active time, passive time and diaphragm relaxation time. A group of 59 women and men (training and non-training) were tested a second time within 5-7 days of the first test to determine the reproducibility of the PImax measurements. Results and conclusion . The measurements were found to be highly reproducible (between the first and second tests no statistically significant differences were found, all spirometric indices included in the study were shown to demonstrate a significant correlation, and total error for all of the analyzed indexes was between 11.1 and 24.3%). Reference ranges for PImax were determined for women and men at different training levels. PImax was shown to have a positive dependence on somatic indices characterizing male and female body mass.

The aim of the study was to examine the possible relationship between I/D polymorphism of ACE gene and selected indices of aerobic capacity among male and female athletes practising winter endurance sports. Sixty-six well-trained athletes (female n = 26, male n = 40), aged 18.4 ± 2.8 years, representing winter endurance sports (cross-country skiing, n = 48; biathlon, n = 8; Nordic combined, n = 10) participated in the study. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. Maximal oxygen consumption (VO2max), maximal running velocity (Vmax) and running velocity at anaerobic threshold (VAT4) were determined in an incremental test to volitional exhaustion on a motorized treadmill. The ACE genotype had no significant effect on absolute VO2max, relative VO2max (divided by body mass or fat free body mass), VAT4 or Vmax. No interaction effect of gender x ACE genotype was found for each of the examined aerobic capacity indices. ACE gene variation was not found to be a determinant of aerobic capacity in either female or male Polish, well-trained endurance athletes participating in winter sports.

Verification of Anaerobic Threshold Indicators for Cross-Country Skiers in Natural Conditons Introduction. The objective of this paper was to verify hart rate values for the anaerobic threshold in cross-country skiers during long-term submaximal intensity training effort. Material and methods. Stress tests were conducted for 6 athletes (4 female and 2 male members of the Polish National Team). The first test involved a graded-intensity laboratory stress test on a mechanical treadmill which consisted of 5-minute exercising periods and enable determining the anaerobic threshold values. The subsequent test (performed within 2-7 days after the first test) involved a submaximal intensity run test based on the determined heart rate (HR) ranges for 400 m on a tartan track. The test involved a 10-minute run done three times at a given intensity based on the HR values for blood lactate level at 4 mmol/l (HRppa), previously determined during the laboratory tests. First exercise: a run at a speed corresponding to HRppa minus 10 bpm, second exercise: HRppa minus 5 bpm and third exercise: HRppa. Results. The verification of the HRppa values recorded in the laboratory tests on a mechanical treadmill confirmed that this indicator is moderately useful for the purpose of selecting the exercise load during race trainings in natural conditions. Conclusion. The race speeds determined on a mechanical treadmill for the anaerobic threshold need to be corrected (increased speed) for the purpose of finding similar exercise load for race trainings in natural conditions.

The aim of the present study was to develop an indirect method of estimating maximal oxygen uptake in oarsmen and oarswomen on the rowing ergometer based on both the submaximal exercises and the commonly used in this sport maximal exercise-type test that simulates rowing the distance of 2000 m. Forty-four oarsmen and 27 oarswomen from both the national team and the direct back-up were enrolled in the investigations. Two exercise tests on the Concept II rowing ergometer were employed: the submaximal test with incremental power output (anaerobic threshold test) and the maximal test, simulating rowing the distance of 2000 m in the shortest possible time (2-km test). During both tests, oxygen uptake and heart rate were recorded and the highest values of these parameters registered during the 2-km test were regarded as the VO2max and HRmax indices, respectively. The linear relation of the oxygen uptake to the power output (W) on the ergometer was detected in both the male (VO2=1.1328+0.0113W) and female (VO2=0.6652+0.0128W) athletes. Comparison of the regression lines demonstrated statistically significant differences between the oarsmen and oarswomen with respect to the intercept and the slope of the lines. Mean values of the directly measured VO2max equaled to 5.48±0.59 and 3.68±0.31 l•min-1 in the groups of oarsmen and oarswomen, respectively. The most accurate predicted values of VO2max were obtained based on the linear regression of VO2max against the mean power output (WM) in the 2-km test using the following formulas: VO2max (l•min-1) in the males = 1.682+0.0097 WM; VO2max (l•min-1) in the females = 1.631+0.0088 WM. In the males, the difference between the measured and predicted VO2max (∆%), correlation coefficient (r), standard estimation error (SEE), and total error (TE%) equaled to 0.12±4.96 (NS), 0.889 (P

Relationships between the postexercise values of blood lactate concentration, pH, oxygen uptake, heart rate, power output on the one hand, and the pre- and postexercise blood cortisol concentrations on the other, were studied in 74 male and 40 female athletes (wrestlers and senior and junior rowers), performing graded exercise of increasing intensity. The senior rowers, junior rowers and wrestlers had different exercise protocols. The senior rowers of both sexes had significantly higher rest concentrations of serum cortisol than the junior athletes. A significant correlation between postexercise lactate concentrations and pre-exercise cortisol concentrations was found in all the male groups (“common”r = 0.515,P < 0.001), but not in the female ones (r = 0.162) . It was concluded that the pre-exercise cortisol concentrations might condition anaerobic-glycolytic metabolism in physical exercise.

Purpose Sphingosine-1-phosphate (S1P) regulates cardiovascular function and plays an important role in muscle biology. We have previously reported that cycling exercise increased plasma S1P. Here, we investigated the effect of exercise duration and intensity on plasma and skeletal muscle S1P levels. Methods In the first experiment, 13 male athletes performed a 60-min exercise at 65 % of VO2max and a graded exercise until exhaustion on a rowing ergometer. Samples of the venous blood were taken, and plasma, erythrocytes and platelets were isolated. In the second experiment, ten male moderately active subjects performed three consecutive periods of one-leg knee extension exercise (at 25, 55 and 85 % of the maximal workload). Muscle biopsies and blood samples from the radial artery and femoral veins were taken. Results Under basal conditions, S1P was released from the leg, as its concentration was lower in the arterial than in the venous plasma (p

Measurement of the maximal inspiratory mouth pressure (PImax) is a simple, reproducible, and non-invasive method frequently used for estimation of the inspiratory muscle strength. The aim of the study was to assess the PImax values in well-trained representatives of the endurance sports and to determine the basic relationships between these values and age, training experience, somatic indices and aerobic capacity of the tested subjects. Overall, thirty female and thirty-five male elite junior and senior representatives of the endurance sports were included in the investigation. PImax and maximal oxygen uptake (VO2max) were estimated in all the subjects. In the female athletes the obtained mean PImax values (118±24 cm H2O) were significantly lower than the respective values estimated in their male counterparts (143±25 cm H2O). Of all the tested relationships significant correlation was detected only between PImax and VO2max in the females (r=0.475) and only between PImax and the body mass index (BMI) in the males (r=0.501). Since the published values of PImax vary greatly depending, among other factors, on the studied population, methods and techniques of the measurement and motivation of the tested subjects it is suggested that each laboratory elaborate its own reference values. The results indicate that in the female and in the male athletes the inspiratory muscle strength is not related to the body size. On the other hand, the detected correlation between PImax and BMI in the males may suggest a possible relationship between the inspiratory muscle strength and the total muscle mass. Presumably, endurance training in the well-trained individuals can not enhance any more the inspiratory muscle strength or the described relationships are indirect and depend on the intersexual differences.