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Öğe Cortisol Awakening Response and Heart Rate Variability in the Menstrual Cycle of Sportswomen(Routledge Journals, Taylor & Francis Ltd, 2021) Kayacan, Yildirim; Makaraci, Yucel; Ozgocer, Tuba; Ucar, Cihat; Yildiz, SedatPurpose: This study aimed to examine the activities of heart rate variability (HRV) and cortisol secretion as markers of the autonomous nervous system (ANS) and the hypothalamic-pituitary-adrenal axis (HPA) during the menstrual cycle in female athletes.Method: Saliva samples of the participants (n = 28) were collected successively at 0, 15, 30, and 60 min after awakening to assess cortisol awakening response (CAR) during each of four phases of the menstrual cycle (the menstruation, ovulation, luteal, and premenstrual phases). Diurnal saliva samples were collected at noon, in the evening (17:00) and 22:00 for cortisol analysis. HRV was measured in the menstrual and premenstrual phases at rest (12:00-14:00).Results: There was no difference betweenCARparameters in the menstrual phases.CARparameters and diurnal cortisol levels were significantly correlated with each other throughout the menstrual cycle. Mean cortisol was a strong predictor of the area under the curve (AUC: S = 0.042; R-Sq = 98.4%). Time-dependent parameters of HRV (standard deviation of the N-N interval [SDNN;P= .049] and the root mean square of the successive R-R differences [rMSSD;P= .038]) were significantly higher in the menstrual phase. There were no correlations betweenCARand HRV parameters.Conclusions: We suggest that the hypothalamic-pituitary-adrenal axis activity and the autonomic nervous system work in a separate manner that is not affected by the menstrual phases in sportswomen. The present study contributed to a better understanding of the relationship between the dynamics of cortisol release and the autonomic nervous system in different phases of the menstrual cycle in female athletes.Öğe Heart Rate Variability and Cortisol Levels Before and After a Brief Anaerobic Exercise in Handball Players(Lippincott Williams & Wilkins, 2023) Kayacan, Yildirim; Makaraci, Yucel; Ucar, Cihat; Amonette, William E.; Yildiz, SedatKayacan, Y, Makaraci, Y, Ucar, C, Amonette, WE, and Yildiz, S. Heart rate variability and cortisol levels before and after a brief anaerobic exercise in handball players. J Strength Cond Res 37(7): 1479-1485, 2023-Evaluating stress in athletes is important for monitoring overall physiologic load and is a core practice for sport performance teams. This study examined relationships between 2 metrics of training stress, heart rate variability (HRV) and cortisol, before and after intense anaerobic power testing. Electrocardiogram recordings and saliva samples were collected before and immediately after a Wingate anaerobic power test (WAnT-30) from professional handball players (n = 20) and sedentary controls (n = 18). Between-group differences and correlations were computed to assess study hypotheses. No differences were observed in HRV frequency-dependent parameters between groups, but in athletes, Min. R-R (p < 0.01) and Avg.R-R (p = 0.03) before WAnT-30 and the percentage of successive normal cardiac beat intervals greater than 50 milliseconds (i.e., pNN50; p = 0.03) after WAnT-30 were elevated. A high positive correlation was detected between the pretest and post-test cortisol levels in athletes (p = 0.0001; r = 0.87) but not in sedentary individuals. No correlations were observed between the cortisol levels and WAnT-30 power parameters in either group. Relationships were evident in the standard deviation of RR intervals (p = 0.02, r = -0.53), square root of the mean squared difference of successive RR intervals (p = 0.043, r = -0.46), very low frequency (p = 0.032; r = -0.480), high-frequency (p = 0.02; r = -0.52) variables, and pretesting cortisol in athletes. These findings suggest that HRV analysis is a valuable tool for examining cardiovascular regulation, independent of cortisol; the data may provide valuable information for performance teams in evaluating acute stress.Öğe The hypothalamic-pituitary-adrenal axis activity in archers: cortisol release, stress, anxiety and success(Edizioni Minerva Medica, 2022) Kayacan, Yildirim; Derebasi, Deniz G.; Ucar, Cihat; Ozgocer, Tuba; Yildiz, SedatBACKGROUND: Archery is a unique sport requiring simultaneous physical and psychological focusing for precisely hitting the small, distant target. Thus, in this sport, the effects of stress and anxiety on success might be more pronounced as a slight deviation in aiming may translate into a large error in meeting the target. Therefore, the current study aimed to assess the interrelationship between anxiety, cortisol awakening response (CAR), cortisol levels during the shooting period, and success in professional male archers during a national tournament. METHODS: Archers (16-20 years old, male, N.=20) shooting with recurve bow participated in the current study during the indoor archery championship. For the assessment of CAR, salivary samples were collected at 0-(wake up), 30-, 45-and 60-min postawakening on three consecutive days, namely qualification, individual elimination, and team shooting days. On the first two days of the shootings (i.e., qualification and elimination), shooting salivary samples were collected at 30 and 15 minutes before the shootings, at half-time and just after the shootings. State and trait anxiety inventory were filled in on the day of registration (the day before qualification shootings). RESULTS: CAR, measured as the area under the curve (AUC), was higher on the elimination day (P=0.038) compared to the qualification day. Shooting cortisol levels were also higher on the elimination day compared to the qualification day (P=0.004). Archers having high rankings on qualification day also had higher success rates on elimination day (r=0.963, P<0.001). CONCLUSIONS: Moderately increased state anxiety, higher CAR, and elevated shooting cortisol levels appear to be the integral components of the elimination stage during a real competition in archery. Thus, assessment of secretion dynamics of cortisol appears to be a valuable objective tool for understanding the neuroendocrine control during the competition days.Öğe Measurement of Salivary Alpha-amylase Activity in Professional Archers by Two Different Methods(Wiley, 2017) Barutcu, Ozlem; Kayacan, Yildirim; Derebasi, Deniz Gunay; Yildiz, Sedat[Abstract Not Available]Öğe Non-invasive Determination of Physiological and Psychological Stress Level of Cortisol Hormone which Comes out of Football Match(Wiley-Blackwell, 2016) Kayacan, Yildirim; Mor, Ahmet; Tapan, Tuba; Ucar, Cihat; Yildiz, Sedat[Abstract Not Available]Öğe Non-Invasive Determination of Stress Hormone Cortisol in Saliva of Elit Archers(Wiley-Blackwell, 2015) Kayacan, Yildirim; Derebasi, Deniz Gunay; Tapan, Tuba; Ucar, Cihat; Yildiz, Sedat[Abstract Not Available]Öğe Psychophysiological stress regulation in football athletes during competition(Edizioni Minerva Medica, 2017) Kayacan, Yildirim; Mor, Ahmet; Ozgocer, Tuba; Ucar, Cihat; Yildiz, SedatBACKGROUND: Exercise brings about endocrinological changes to balance homeostasis during challenging coordinative movements, thus leading to physiological and psychological stress. The present study aimed to assess, by non-invasive means, the stress levels and cortisol awakening responses (CAR) of athletes playing a football match. METHODS: Male football (soccer) players (N.=14, age 21.3 +/- 3.25 years) in a regional professional league took part in the study. To determine cortisol responses, saliva samples were taken on 3 different days during a regular league match. The salivary cortisol levels of the athletes were analyzed by ELISA. All participants were asked to fill in STAI-T questionnaires. The repeated measures test was used for cortisol comparisons between the sampling times and for CAR comparisons between days. RESULTS: According to the analyses, CAR levels decreased on the game day and increased the day after. As the competition time approached, the values beginned to rise but returned to initial values half time. At the end of the match, a slight increase was observed. There were no statistically significant differences in CAR and competition samples. There were no correlations between cortisol parameters and STAI-T scores (P>0.05). CONCLUSIONS: Football is a team sport requiring coordinated team effort and this appeared to incluence current data. Moreover, significant hormonal fluctuations related to competition revealed that professional football players are well adapted to the competition releated stress.Öğe Resting and postexercise heart rate variability in professional handball players(Edizioni Minerva Medica, 2016) Kayacan, Yildirim; Yildiz, SedatBACKGROUND: The aim of this study was to evaluate heart rate variability (HRV) in professional handball players during rest and following a 5 min mild jogging exercise. METHODS: For that purpose, electrocardiogram (ECG) of male handball players (N.=12, mean age 25 +/- 3.95 years) and sedentary controls (N.=14, mean age 23.5 +/- 2.95 years) were recorded for 5 min at rest and just after 5 min of mild jogging. ECGs were recorded and following HRV parameters were calculated: time -domain variables such as heart rate (HR), average normal-to-normal RR intervals, standard deviation of normal-to-normal RR intervals, square root of the mean of the squares of differences between adjacent NN intervals, percentage of differences between adjacent NN intervals that are greater than 50 milliseconds (pNN50), and frequency -domain variables such as very low frequency, low (LF) and high frequency (HF) of the power and LF/IF ratio. Unpaired t-test was used to find out differences among groups while paired t-test was used for comparison of each group for pre- and postjogging HRV. Pearson correlations were carried out to find out the relationships between the parameters. RESULTS: Blood pressures were not different between handball players and sedentary controls but exercise increased systolic blood pressure (P<0.01). HR was increased with exercise (P<0.001) and was slower in handball players (P<0.01). QTc was increased with exercise (P<0.001) and was higher in handball players (P<0.001). Exercise decreased pNN50 values in both groups but LF/HF ratio increased only in sedentary subjects. CONCLUSIONS: In conclusion, results of the HRV parameters show that sympathovagal balance does not appear to change in handball players in response to a mild, short-time (5 min) jogging exercise. However, in sedentary subjects, either the sympathetic regulation of the autonomous nervous system increased or vagal withdrawal occurred.Öğe Salivary Cortisol Levels in Elite Male Handball Players during a Match(Wiley-Blackwell, 2015) Kayacan, Yildirim; Tapan, Tuba; Makaraci, Yucel; Ucar, Cihat; Yildiz, Sedat[Abstract Not Available]
