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Öğe Development of the Effect of Video Assistant Referee Application on Football Parameters(Mdpi, 2022) Buyukcelebi, Hakan; Duz, Serkan; Acak, Mahmut; Nalbant, Umut; Svatora, Karel; Gabrys, Tomasz; Karayigit, RaciThe Video Assistant Referee (VAR) application is a technological development that gives referees the chance to review their critical decisions. The current study aimed to determine the effect of the VAR system in international football organizations on the game over the years. The sample of the study consists of 115 football matches, specifically 64 matches played in the 2018 FIFA World Cup and 51 matches played in the 2020 European Football Championship. In the competitions handled, the number of goals, the number of yellow cards, the number of red cards, the first half time, the second half time, the total match time, the number of penalties and the number of offsides were examined. The Mann-Whitney U test was used to compare two independent groups. As a result, in the 2020 European Football Championship, there was a decrease in the second half time (p = 0.01) and total match time (p = 0.01), and a significant increase in the number of offsides (p = 0.03) compared to the 2018 FIFA World Cup. On the other hand, there was no significant difference between the two tournaments in the variables of number of goals, number of yellow cards, number of red cards, half time and penalty shootout (p > 0.05). In light of the data obtained, it can be said that the effect of the VAR system on the spirit of the game will decrease as the share of the VAR system in the pauses during the competition decreases over the years. The data revealed in the study may be a clue to explaining why the effect of the VAR system on game dynamics and game spirit has decreased over the years. Therefore, the concerns of football stakeholders about the effects of the system on the game may gradually decrease with the arrangements made for VAR.Öğe Low and Moderate Doses of Caffeinated Coffee Improve Repeated Sprint Performance in Female Team Sport Athletes(Mdpi, 2022) Karayigit, Raci; Forbes, Scott C.; Osmanov, Zakir; Yilmaz, Canan; Yasli, Burak Caglar; Naderi, Alireza; Buyukcelebi, HakanSimple Summary The bulk of research on caffeine as an ergogenic aid has been on endurance performance, however there is evidence that caffeine can enhance short-term high-intensity performance. Caffeine may have an ergogenic impact during anaerobic exercise by facilitating central effects by antagonizing adenosine receptors, hence decreasing the detrimental effects of adenosine on neurotransmission, arousal, and pain perception. Caffeine intake also activates the central nervous system, which promotes alertness and concentration. Additionally, athletes typically consume coffee containing caffeine. To date, the bulk of study has focused on the administration of 3-9 mg/kg of anhydrous caffeine, as opposed to the readily accessible source of caffeine, coffee, and has mostly been conducted on males. Consequently, there is a dearth of study evaluating the ergogenic impact of caffeine on females, particularly when consuming alternative caffeine delivery methods, such as coffee. The current study is the first to investigate the effects of low (3 mg/kg) and moderate (6 mg/kg) doses of caffeine from coffee on repeated sprint performance in females. The aim of this study was to determine the effect of low and moderate doses of caffeine ingestion via caffeinated coffee on repeated sprint test (RST) and plasma catecholamine concentration in trained female team-sport athletes. In a randomized, double-blind, crossover design, 13 female team-sport athletes (VO2max: 48.7 +/- 4 mL center dot kg center dot min(-1)) completed three RST trials, separated by 4-day, 60 min post-ingestion of either 3 mg center dot kg(-1) (LCOF) or 6 mg center dot kg(-1) (MCOF) or placebo (PLA). The RST consisted of 12 x 4 s sprints on a cycle ergometer interspersed with 20 s of active recovery. Blood lactate (BLa) and glucose (GLU) and epinephrine and norepinephrine concentrations were collected before and 60 min after coffee ingestion, and after RST. Heart rate (HR) and ratings of perceived exertion (RPE) were measured at the beginning of RST, and after the 6th and 12th sprints. Average peak power score during RST was significantly improved after LCOF (p = 0.016) and MCOF (p = 0.041) compared to PLA, but peak and mean power output of the individual sprints, and fatigue index were not different between trials (all p > 0.05). Epinephrine and norepinephrine concentrations were significantly higher before and after RST in LCOF and MCOF compared to PLA (all p < 0.05). BLa was also higher after RST in both LCOF and MCOF compared to PLA (p = 0.005). HR, RPE, and GLU were not different between conditions (p > 0.05). In conclusion, low and moderate dose of caffeine ingestion can enhance the average peak power score during repeated sprints. These findings partly support low and moderate doses of caffeine supplementation via coffee as a nutritional ergogenic aid for trained female team-sport players during repeated sprint exercise.Öğe Relationship between quadriceps muscle architecture and lower limb strength and physical function in older adults community-dwelling individuals: a cross-sectional study(Frontiers Media Sa, 2024) Cinarli, Fahri Safa; Ulubaba, Hilal Er; Ucar, Ozan; Kilinc, Deniz Can; Ciftci, Rukiye; Karayigit, Raci; Aldhahi, Monira, IBackground and objective: Factors related to muscle architecture may lead to functional limitations in activities of daily living in the older adults. This study aimed to investigate the relationship between quadriceps femoris (QF) architecture and physical function in older adults community-dwelling people. Methods: The study included 25 community-dwelling older adults participants aged over 60 years (14 women and 11 men) who were not engaged in regular physical activity. The rectus femoris (RF) and vastus intermedius (VI) muscle thicknesses as well as the RF cross-sectional area (CSA) were assessed using 2D ultrasonography. The 30 Seconds Chair Stand test (30sCST) and Timed Up and Go Test (TUG) were used to assess lower body muscle power and functional mobility, respectively. Results: The QF muscle architecture showed moderate and large correlations with the 30sCST (r range = 0.45-0.67, p < 0.05) and TUG (r range = 0.480-0.60, p < 0.05). RF thickness was a significant (p < 0.01) independent predictor of 30sCST (R-2 = 0.45) and TUG (R-2 = 0.36). VI thickness was a significant (p < 0.05) independent predictor of 30sCST (R-2 = 0.20) and TUG (R-2 = 0.231). RF CSA was a significant independent predictor of the 30sCST (R-2 = 0.250, p < 0.05) and TUG (R-2 = 0.27, p < 0.01). Multiple linear regression models explained 38% of the 30sCST variance and 30% of the TUG variance in the older adults group. Conclusion: Quadriceps muscle group directly affects basic activities of daily living in the older adults. Ultrasound measurements, which are non-invasive tools, are extremely valuable for understanding the limitations of activities of daily living in the older adults.Öğe Relationship between Unilateral Leg Extension Strength and Dynamic Balance in Healthy Young Men(Mdpi, 2022) Cinarli, Fahri Safa; Adanur, Oguzhan; Esen, Ozcan; Barasinska, Magdalena; Cepicka, Ladislav; Gabrys, Tomasz; Karayigit, RaciIt is well known that the quadriceps muscle group is involved in activity during dynamic balance and that dynamic balance tests are an important feedback tool for predicting lower limb injuries. However, the relationship between maximum leg extension strength and performance in the Y Balance Test is not fully known. The aim of this study was to investigate the relationship between unilateral leg extension strength and dynamic balance in healthy young men. The study was conducted as a cross-sectional study. A total of 33 healthy men (mean age +/- standard deviation = 21.21 +/- 1.24 years) volunteered for this study. The participants' dynamic balance was determined with the Y Balance Test and unilateral one repetition maximum strength was determined by the leg extension machine. The same side was preferred for strength and dynamic balance measurements. Normalized reach, composite score, and absolute and relative strength values were analyzed for correlations. Linear regression analysis was used to determine whether strength values predicted the results of the Y Balance Test. There was a positive linear correlation between the strength values and normalized reach distances and composite scores (r ranges from 0.466 to 0.757; p < 0.01). The coefficients of determination showed that dynamic balance and strength (absolute and relative) performance are not independent parameters in healthy young men (r(2) = 21-57% explained variance). It was also found that strength values (absolute and relative) can predict balance. Our study confirmed the relationship between strength and dynamic balance. It can be said that especially the strength of the lower extremity has an acceptable effect on dynamic balance.