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Purpose: This study aimed to determine whether the initial levels of aerobic fitness and hematological variables in young female road cyclists are related to their athletic performance development during their careers. Methods: Results of graded exercise tests on a cycle ergometer and total hemoglobin mass (tHb-mass) measurements were analyzed in 34 female road cyclists (age 18.6 [1.9] y). Among them, 2 groups were distinguished based on their competitive performance (Union Cycliste Internationale world ranking) over the following 8 years. Areas under the curve in receiver-operating-characteristic curves were calculated as indicators of elite-performance prediction. Results: Initial graded exercise test variables (peak power, peak oxygen uptake, and power at 4 mmol/L blood lactate) were not significantly different in elite (n = 13) versus nonelite (n = 21) riders. In contrast, elite riders had higher tHb-mass expressed either in absolute measures (664 [75] vs 596 [59] g, P =.006) or normalized to body mass (11.2 [0.8] vs 10.3 [0.7] g/kg, P =.001) and fat-free mass (14.4 [0.9] vs 13.1 [0.9] g/kg, P <.001). Absolute and relative erythrocyte volumes were significantly higher in elite subjects (P ranged from <.001 to.006). Of all the variables analyzed, the relative tHb-mass had the highest predictive ability to reach the elite level (area under the curve ranged from.82 to.85). Conclusion: Measurement of tHb-mass can be a helpful tool in talent detection to identify young female road cyclists with the potential to reach the elite level in the future. [ABSTRACT FROM AUTHOR]

The effect of strenuous exercise on sleep patterns in swimmers is equivocal. Therefore, the purpose of the study was to describe possible changes in sleep parameters among elite swimmers subjected to different training loads (TL). Methods: Eighteen elite swimmers (8 females) were monitored across two high-volume preparatory 1-wk periods (P1, P2) and a lower-volume tapering 1-wk period (P3) before a major competition. Internal (the session rating of perceived exertion [sRPE]) and external TL (training duration and volume) were measured, along with several sleep indices (e.g., bedtime, get-up time, sleep time, wake after sleep onset [WASO]). Serum measurements of urea, creatine kinase (CK), testosterone and cortisol were taken before and after training sessions at the beginning (Mondays) and end (Fridays) of each micro cycle. Athlete TL decreased significantly in a stepwise manner from P1 to P2 and from P2 to P3. Of all sleep parameters, only significant differences in bedtime and getup time emerged (P3 > P1 and/or P2). Sleep duration (~6.3 h) or quality (WASO: 41-45 min) were also unaffected by TL. CK levels declined from P1 to P3 (d = -0.8), and from P2 to P3 (d = -0.6). Positive exercise-induced changes in CK were also seen in each training period. The other biomarkers did not show the same temporal or acute patterns. Irrespective of the TL, the monitored swimmers experienced insufficient and fragmented sleep across this study. Neither sleep quality nor quantity were affected by different magnitudes of TL. Among the biochemical markers of fatigue, baseline plasma CK activity best reflected the physiological response to TL. [ABSTRACT FROM AUTHOR]

Purpose: Sauna bathing is recommended to improve the sports training process, yet empirical evidence confirming its effectiveness is still inconclusive. We examined the effects of post-exercise sauna bathing on hematological adaptations and exercise capacity in healthy men. Methods: Thirteen physical education students participated in randomized cross-over study: two, 4-week interventions, with 10-week washout. The interventions involved 3 times per week 60-min stationary cycling either with 30-min of post-exercise sauna bathing (89 ± 3°C, 10 ± 2% RH) or without; no fluid was ingested during both exercise and sauna sessions. Before and after both interventions, participants were tested for total hemoglobin mass (tHb-mass), intravascular volumes, erythropoietin, ferritin, red blood cell parameters with reticulocyte fractions, along with maximal/peak and submaximal variables in a graded exercise test (GXT). Results: Regardless of intervention type, tHb-mass increased (p =.014) whereas ferritin concentration decreased (p =.027); however, changes in tHb-mass were within the range of typical error (<1.8%). Absolute and relative values of maximal power and power at gas exchange threshold, as well as peak oxygen uptake (all p <.010), also increased irrespective of intervention type. Conclusions: The use of post-exercise sauna bathing with fluid intake restrictions does not provide any additional benefits in tested variables over endurance training alone. Thus, further evidence is required before recommendations to utilize this post-exercise conditioning strategy are deemed valid. [ABSTRACT FROM AUTHOR]

Malczewska-Lenczowska, J, Orysiak, J, Majorczyk, E, Sitkowski, D, Starczewski, M, and Żmijewski, P. HIF-1α and NFIA-AS2 polymorphisms as potential determinants of total hemoglobin mass in endurance athletes. J Strength Cond Res 36(6): 1596–1604, 2022—The aims of this study were to examine (1) the genotype distribution of rs11549465:C>T of the HIF-1α gene and rs1572312:C>A of the NFIA-AS2 gene; (2) the association between the genes and hematological status in endurance-oriented athletes; and (3) the association between the NFIA-AS2 gene and aerobic capacity in cyclists. Two hundred thirty-eight well-trained athletes (female n = 90, male n = 148) participated in the study. Total hemoglobin mass (tHbmass), blood morphology, intravascular volumes, i.e., erythrocyte volume (EV), blood volume (BV) and plasma volume (PV), and aerobic capacity indices, e.g., peak oxygen uptake (V̇ o 2peak), and power at anaerobic threshold (PAT) were determined. In both studied genes, the CC genotype was predominant. In the HIF-1α gene, there were no differences in genotype and allele distribution among athletes from different disciplines and between sexes. The distribution of genotypes and alleles of the NFIA-AS2 gene differed significantly in male athletes; the frequency of A allele carriers (CA + AA) was significantly higher in cyclists than in rowers and middle- and long-distance runners. The athletes with CC genotype of NF1A - AS2 had significantly higher relative values of: tHbmass (total female athletes, cyclists), PV, BV (cyclists), and EV (total male athletes, cyclists) and PAT (cyclists) than A allele carriers (CA + AA genotypes). In conclusion, our study indicates that NFIA-AS2 rs1572312:C>A polymorphism was associated with hematological status in endurance athletes, as well as aerobic capacity indices in male cyclists. It suggests that this polymorphism may be a determinant of quantity of hemoglobin and intrtavascular volumes, which in turn can have an impact on aerobic performance. [ABSTRACT FROM AUTHOR]

The study was designed to assess the usefulness of routine electrocardiography (ECG) as well as transthoracic echocardiography (TTE) in screening top level endurance athletes. An additional goal was to attempt to identify factors determining occurrence of adaptive and abnormal changes in ECG and TTE. The retrospective analysis included basic medical data, ECG and TTE results of 262 athletes (123 rowers, 32 canoeists and 107 cyclists), members of the Polish National Team. The athletes were divided into two age groups: young (≤ 18 years; n = 177) and elite (> 18 years; n = 85). ECG and TTE measurements were analysed according to the International Recommendations from 2017 and 2015, respectively. Adaptive ECG changes were found in 165 (63%) athletes. Abnormal ECG changes were identified in 10 (3.8%) athletes. 98% of athletes exceeded TTE norms for the general population and 26% exceeded norms for athletes. The occurrence of both adaptive ECG findings and abnormalities in the TTE (in norms for athletes) was strongly associated with the years of training, hours of training per week and the age of the athlete. Male gender and the years of training were independent predictors of the ECG and TTE findings. Abnormal ECG changes were not related to the time of sport. Among 10 athletes with ECG changes, only 3 had changes in TTE and no relationship was found between abnormal finding in ECG and TTE (p = 0.45). ECG and TTE screening complement each other in identifying endurance athletes requiring treatment or verification. Unlike abnormal ECG changes, adaptive ECG changes and TTE abnormalities are strongly related to the training duration, which reflects physiological adaptation of the heart to physical exertion in high endurance athletes. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine upper respiratory tract infections (URTI) and their associations with resting saliva and blood immune and endocrine parameters in ice hockey players. Twenty-seven participants (age 16.5 ± 0.5 years) completed the 24-week study period. The counts/concentrations of immune and endocrine markers were compared between healthy-prone athletes (≤2 episodes of URTI during the study period) and illness-prone athletes (≥3 episodes of URTI) and between the URTI state (when athletes had infections) and the healthy state (the time without URTI). There were no differences in concentration/counts of saliva and blood immune and endocrine parameters between the illness-prone and illness-free athletes. Athletes had significantly lower sIgA, sIgA1 and sIgA2 concentrations (sIgA: 119.88 ± 66.88, 144.10 ± 75.0 µg/ml; sIgA1: 90.2 ± 40.64, 108.44 ± 29.8 U; sIgA2: 67.58 ± 30.1, 80.3 ± 25.61 U, respectively) and significantly higher WBC, neutrophil, monocyte and eosinophil count values and IL-1ra concentration at the time when they had symptoms of URTI than in the period without symptoms of infections. There were no differences in salivary cortisol concentration between the period of URTI symptoms and the period without URTI symptoms. In conclusion, we observed lower concentrations of salivary immunoglobulins and higher levels of blood immune parameters during URTI in athletes, which may confirm the suppression of mucosal immunity and initiation responses to pathogenic infections by innate immunity. [ABSTRACT FROM AUTHOR]

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Although there is no common agreement among authors about the transferability of the laboratory results to natural conditions, the Intensity of water training in canoeing is nevertheless customarily determined on the basis of ergometer tests. Therefore the objective of this study was to compare HR values referring to LA blood level of 4 mmol/1 (HRAT4), obtained in diverse conditions. At three days' intervals eight canoeists underwent two stress tests on water and a laboratory test on the Dansprint ergometer. The tests were used to determine HRAT4, and to verify whether its constant level during the training will increase LA content to values oscillating at 4 mmol/l. No significant differences were determined between HRAT4 values obtained during on-water and ergometer tests. Following the exercise test to verify the accuracy of the procedure designed to determine the on-water HRAT4 values, the lactate levels fell on average within the range of 3.99±0.55 mmol· l-1. Even though the HRAT4 values obtained during on-water and ergometer tests were shown to be strongly correlated (R2=0.892, p≤0.001, SEE=2.771), the limit of agreement varied from -5.5 to +5.7 s/mm. The final conclusion of this study is that a exercise test conducted in special conditions offers a relatively accurate method of determining the intensity corresponding to AT4 in the same conditions. While the results of such tests are closely correlated with the ergometer results, their verification is nevertheless understandable when applying laboratory results to on-water training. [ABSTRACT FROM AUTHOR]

Copyright of Polish Journal of Sport & Tourism is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background. The paper presents the influence of maximal exertion time on postexercise fluctuations of blood cortisone and testosterone concentrations. Material and methods. Ten canoeists participated in exercise laboratory tests on two subsequent days at the sime time of the day (10.00-12.00). On the first day blood samples were taken at rest in the morning (8.00) and then sportsmen performed shorter (40 sec.) maximal exertion (SME). On the second day they performed longer (4 min.) maximal exertion (LME). Blood cortisone and testosterone concentrations were assessed in blood samples taken in the morning before tests (-5 min.) and during postexercise restitution (+0, +3, and +30 min.). Results. Cortisol levels measured before SME (847±151) and LME (789±123 nmol/L) were higher (p<0.05) than in the morning (570±130 nmol/L). The only statistically significant increase in cortisol levels after both exertions was noted in +30 minute of restitution to 1107±197 and 942±148 nmol/l, after SME and LME, respectively. There was negative correlation (r=-0.782, p<0.05) between SME and increment of concentrations in +0 and +3 min. Mean individual changeability between +0 and +3 minute was more prominent after SME (CV=17%) than after LME (4.9%). Mean intrapersonal changeability was lower for testosterone than for cortisol. Between +0 and +3 minute mean blood lactate concentration increased (p<0.0%) from 9.4 to 14.7 mmol/L after SME, but not after LME (from 12.5 to 12.9 mmol/L). Conclusions. The magnitude of fluctuations after maximal exertion depends on its duration. After short-time exertion maximal lactate concentration is observed a few minutes later than after longer-time exertion. [ABSTRACT FROM AUTHOR]