Browsing by Author "Nobari, Hadi"
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- Acute and chronic workload ratios of perceived exertion, global positioning system, and running-based variables between starters and non-starters: a male professional team studyPublication . Nobari, Hadi; Alijanpour, Nader; Martins, Alexandre Duarte; Oliveira, RafaelThe study aim was 2-fold (i) to describe and compare the in-season variations of acute: chronic workload ratio (ACWR) coupled, ACWR uncoupled, and exponentially weighted moving average (EWMA) through session-rated perceived exertion (s-RPE), total distance (TD), high-speed running distance (HSRD), and sprint distance across different periods of a professional soccer season (early, mid, and end-season) between starters and non-starters; (ii) to analyze the relationship the aforementioned measures across different periods of the season for starters and non-starters. Twenty elite soccer players (mean±SD age, 29.4±4.4 y; height, 1.8±0.1m; and body mass, 74.8±2.3kg). They were divided into starter and non-starter groups and were evaluated for 20weeks. ACWR had general changes throughout the season. At the beginning and end of the mid-season, the highest ACWR was observed in three parameters: s-RPE, TD, and HSRD. ACWR and EWMA through sprint distance were higher at the beginning of the early-season than at any other time of the season. The ACWR coupled of s-RPE shows a significant higher value for non-starters than starters (p=0.015; g=−1.01 [−1.98, −0.09]) and the ACWR coupled of TD shows a significant higher value for starters than non-starters in early-season (p<0.01; g=3.01 [1.78, 4.46]) and shows a significant higher value for non-starters than starters in mid-season (p<0.01; g=−2.52 [−3.83, −1.39]), and end-season (p<0.01; g=−2.57 [−3.89, −1.43]). While the EWMA of TD shows a significant higher value for starters than non-starters in early season (p<0.01; g=2.25 [1.17, 3.49]) and mid-season (p<0.01; g=2.42 [1.31, 3.71]), and shows a significant higher value for non-starters than starters in end-season (p<0.01; g=−2.23 [−3.47, −1.16]). Additionally, we found some correlations between external and internal load measures during three periods of the in-season. The study’s main finding was that the indexes of ACWR and EWMA were useful to detect differences between period and between playing status with the exception for the sprint variable. In addition, the necessary work for non-starter players’ improvement is not done during training, and these players lose their readiness as the season progresses. Consequently, these players perform poorly during the match. Therefore, coaches and their staff should consider devising new activities to keep non-starter players physically fit. This deficit must be accounted for in training because they compete in fewer matches and have less burden than starters.
- Are acute:chronic workload ratios of perceived exertion and running based variables sensible to detect variations between player positions over the season? A soccer team studyPublication . Nobari, Hadi; Arslan, Ersan; Martins, Alexandre Duarte; Oliveira, RafaelBackground: The aim of this study was to describe and compare the in-season variations of acute: chronic workload ratio (ACWR) coupled, uncoupled, and exponentially weighted moving average (EWMA) through session rating of perceived exertion (s-RPE), total distance (TD), high-speed running distance (HSRD) and sprint distance (SPRINT) in three diferent periods of an elite soccer season according to player positions. Methods: Twenty male elite players (age: 29.4±4.4) from an Asian First League team were daily monitored for twenty consecutive weeks during the 2017–2018 in-season. Forty-seven trainings and twenty matches were moni tored using global positioning system units (GPS) to collect TD, HSRD and SPRINT. Through the collection of s-RPE, TD, HSRD, and SPRINT by ACWR and EWMA were calculated for each training session. Results: The results revealed that according to diferent periods of the season, workload measures observed in mid season were meaningfully higher compared with early-season (g=ranging from 0.53 to 4.98) except for EWMASPRINT. In general, wingers and strikers tended to have greater scores in workload measures compared to the defenders and midfelders (g=ranging from 0.41 to 5.42). Conclusions: These fndings may provide detailed information for coaches and sports scientists regarding the vari ations of acute and chronic workload ratio and external loading in-season and between player positions in an elite soccer team
- Association between 2D:4D ratios and sprinting, change of direction ability, aerobic fitness, and cumulative workloads in elite youth soccer playersPublication . Nobari, Hadi; Eken, Özgür; Prieto-González, Pablo; Oliveira, Rafael; Brito, JoãoBackground The aim of this study was two-fold: (i) to determine the correlation between 2D:4D, maximal oxygen uptake (VO2max), body fat percentage (BF%), maximum heart rate (HRmax), change of direction (COD), and accumulated acute and chronic workload variables; (ii) to verify if the length of the second digit divided by fourth digit (2D:4D) can explain fitness variables and accumulated training load. Methods Twenty elite young football players (age: 13.26±0.19 years; height: 165.8±11.67 cm; body mass: 50.70±7.56 kg; VO2max, 48.22±2.29 ml.kg−1 .min−1 ) participated in the present study. Anthropometric and body composition variables (e.g., height, body mass, sitting height, age, BF%, body mass index, right and left finger 2D:4D ratios) were measured. The following fitness tests were also conducted: 30−15 Intermittent Fitness Test (VO2max and HRmax), COD (5-0-5 agility test), and speed (10-30msprint test. HRmax and the training load were also measured and monitored using the Rate of Perceived Exertion during the 26 weeks. Results There were associations between HRmax and VO2max, between 2D and 4D lengths and Left and Right hand ratios. Also, in AW with Right and Left 4D. The CW and de ACWR with the Right 4D. There were other associations between physical test variables and workload variables. Conclusions Under-14 soccer players with low right and left-hand 2D:4D ratios did not perform better in the selected fitness tests to assess VO2max, COD, or sprint ability. However, it cannot be ruled out that the absence of statistically significant results may be related to the small sample size and the maturational heterogeneity of the participants.
- Associations among maturity, accumulated workload, physiological, and body composition factors in youth soccer players: a comparison between playing positionsPublication . Nobari, Hadi; Eken, Özgür; Prieto-González, Pablo; Brito, João; Oliveira, RafaelThe purposes of this study were: (i) to analyze the correlation between accumulated workload (AW)—based on season periods—with maturity, linear sprints, maximum oxygen uptake (VO2max), maximum heart rate, and body composition; and (ii) to compare the playing positions based on the mentioned parameters. Twenty-one elite soccer players under the age of 14 participated in the study. They were divided into five groups based on playing positions. The in-season weekly AW was recorded for 26 weeks into two separated periods of 13 weeks (AW-1 and AW-2). Similarly, the following parameters were assessed: body mass, standing and sitting height, body mass index, body fat percentage, maturity offset, age at peak height velocity (PHV), sprinting ability (10 m and 30 m), and VO2max. The main significant differences between playing positions were found for weight, height, sitting height, and sprinting at 10 m and 30 m. No correlation was observed between AW (based on periods) and maturity or between VO2max and AW-2. AW-1 denoted a large positive correlation with AW-2. AW-1 had a moderate negative correlation with VO2max, whereas PHV and maturity presented a strong negative correlation. Young soccer players’ maturity statuses and fitness levels do not imply differences between AW-1 and AW-2. However, the higher the AW in the first half of the season, the higher the AW in the second half. The absence of significant differences between player positions could be associated with the similar training regardless of the playing position. Moreover, soccer positively influences performance in short sprints (10 m), midfielders being the fastest.
- Comparação De Variáveis De Corrida E Do “Body Load” Com Base Nos Resultados Dos Jogos (Vitória, Empate, Derrota) Em Jogadores Profissionais De FutebolPublication . Oliveira, Rafael; Brito, João Paulo; Perez-Gomez, Jorge; Clemente, Filipe Manuel; Ardigò, Luca; Nobari, Hadi
- Comparison of external load measures per minute based on match seasonal periods and playing positions of a soccer Turkish super league teamPublication . Akyildiz, Zeki; Yüksel, Yılmaz; Birgonül, Yaşar; Ceylan, Halil İbrahim; Oliveira, Rafael; Çene, Erhan; Parim, Coskun; Clemente, Filipe Manuel; Nobari, HadiBackground Turkish Super League teams need more information about the external load. Considering the specific country and the coaches’ philosophies, the purpose of this study was to compare the external match load of a Turkish Super League team considering the different playing positions and in-season periods. Methodology A longitudinal study design was employed by observing 29 official matches of the same team. A total of fifteen players, consisting of five defenders, five midfielders, and five forwards, were analyzed using the Sentio Sports Optical Tracking System. The following outcomes were extracted in each match: total distance (TD), walking [from 0 to 7.2 km/h], jogging [from 7.2 to 14.4 km/h], running [from 14.4 to 20 km/h], high speed running (HSR) [>20 km/h], metabolic power (MP), maximum deceleration (Decmax) [Dec < -3 m/s2], total deceleration distance (Dectotal), maximum acceleration (Accmax) [Acc>3 m/s2], and total acceleration distance (Acctotal). Statistical analysis consisted of ANOVA and Bonferroni correction post hoc tests. Results The main results showed that all variables were similar between periods of the season (p>0.05) except for walking (p=0.021 witha large effect size), which revealed lower values in the mid-season period. When analyzing periods of the season considering playing positions, there were several significant results for TD, walking, jogging, running, HSR, Dectotal and Acctotal (p<0.05, with small to large effects). A tendency for higher values was noted in the mid and end-season. Considering the playing positions comparisons, midfielders showed higher values than defenders for TD, MP, Dectotal and Acctotal (p<0.05 with large effect for all). Midfielders also showed higher values than forwards for TD, jogging, Dectotal and Acctotal (p<0.05 with a large effect for all).Conclusions The present study emphasizes the significance of analyzing data based on minute, playing position, and season period. Findings reveal that defenders consistently displayed the lowest values in all external load measures during matches compared to other positions throughout the season. Furthermore, midfielders demonstrated a higher activity profile during the initial and middle stages of the season compared to other positions, with a slight tendency to decrease load towards the end of the season.
- Comparison of GPS derived variables based on home versus away matches in the Asian professional soccer teamPublication . Nobari, Hadi; Fani, Maryam; Mainer-Pardos, Elena; Oliveira, RafaelProfessional soccer with high training loads is defined with weekly competition. The purpose of this study was to com pare external training load data of GPS derived variables that preceded a home versus away match. Twenty-two weeks of a national league meet schedule were analyzed, which included 11 home and 11 away matches. Twelve professional soccer players (age, 28.6 6 2.7 years; height, 182.1 6 8.6 cm; BMI, 22.6 6 0.7 kg/m2 ) participated in this study. All matches were monitored using GPSPORTS systems Pty Ltd. The following variables were selected: total duration of the matches and training sessions, high-speed running distance (18–23 km h21 ), sprint distance (. 23 km h21 ), maxi mal speed, body load, metabolic power, accelerations Zone1 (\ 2ms22 ) (AccZ1), accelerations Zone2 (2 –4 m s22 ) (AccZ2), accelerations Zone3 (. 4ms22 ) (AccZ3), decelerations Zone1 (\ 22ms22 ) (DecZ1), decelerations Zone2 (22 to 24ms22 ) (DecZ2) and decelerations Zone3 (. 24ms22 ) (DecZ3). The results indicated that meta bolic power showed higher values at home than away matches [p = 0.047, ES = 0.53, (20.28, 1.34)]. Furthermore, there was a higher value in accumulated external training load that preceded away matches for high-speed running and lower value [p \ 0.001, ES = 20.95 (21.79, 20.10)] for DecZ1 than home matches. In conclusion, external load variables had a higher value in home matches. However, the results showed that high-speed running was higher in away matches, which could be the discretion of the coaches to prepare players for different conditions on the oppo nent’s field.
- Comparison of measurements of external load between professional soccer playersPublication . Gholizadeh, Roghayyeh; Nobari, Hadi; Bolboli, Lotfali; Siahkouhian, Marefat; Brito, JoãoBackground: The excessive and rapid increases in training load (TL) may be responsible for most non-contact injuries in soccer. This study’s aims were to describe, week(w)-by-week, the acute (AW), chronic (CW), acute:chronic workload ratio (wACWR), total distance (wTD), duration training (wDT), sprint total distance (wSTD), repeat sprint (wRS), and maximum speed (wMS) between starter and non-starter professional soccer players based on different periods (i.e., pre-, early-, mid-, and end-season) of a full-season (Persian Gulf Pro League, 2019–2020). Methods: Nineteen players were divided according to their starting status: starters (n = 10) or non-starters (n = 9). External workload was monitored for 43 weeks: pre- from w1–w4; early- from w5–w17; mid- from w18–w30, and end-season from w31–w43. Results: In starters, AW, CW, and wACWR were greater than non-starters (p < 0.05) throughout the periods of early- (CW, p≤0.0001), mid- (AW, p = 0.008; CW, p ≤ 0.0001; wACWR, p = 0.043), or end-season (AW, p = 0.035; CW, p = 0.017; wACWR, p=0.010). Starters had a greater wTD (p ≤ 0.0001), wSTD (p≤0.0001 to 0.003), wDT (p≤0.0001 to 0.023), wRS (p ≤ 0.0001 to 0.018), and wMS (p ≤ 0.0001) than non-starters during early-, mid-, and end-season. Conclusion: Starters experienced more CW and AW during the season than non-starters, which underlines the need to design tailored training programs accounting for the differences between playing status.
- Comparison of official and friendly matches through acceleration, deceleration and metabolic power measures: a full-season study in professional soccer playersPublication . Nobari, Hadi; Khalili, Sara Mahmoudzadeh; Oliveira, Rafael; Castillo-Rodríguez, Alfonso; Pérez-Gómez, Jorge; Ardigò, Luca PaoloSoccer is a popular team sport and highly demanding activity that requires high effort and long-term training plans. The goals of this study were to compare the accelerations, decelerations and metabolic power between official and friendly full matches, between the first and second halves of the matches, and between both halves of official and friendly matches. Twelve professional soccer players (age, 28.6 ± 2.7 years; height, 182.1 ± 8.6 cm; body mass, 75.3 ± 8.2 kg; BMI, 22.6 ± 0.7 kg/m2) participated in this study. A total of 33 official and 10 friendly matches were analyzed from the Iranian Premier League. All matches were monitored using GPSPORTS systems Pty Ltd. The following variables were selected: total duration of the matches, metabolic power, accelerations Zone1 (<2 m·s-2) (AccZ1), accelerations Zone2 (2 to 4 m·s-2) (AccZ2), accelerations Zone3 (>4 m·s-2) (AccZ3), decelerations Zone1 (<-2 m·s-2) (DecZ1), decelerations Zone2 (-2 to -4 m·s-2) (DecZ2) and decelerations Zone3 (>-4 m·s-2) (DecZ3). The major finding was shown in metabolic power, where higher values occurred in friendly matches (p < 0.05 with small effect size). Furthermore, total duration, AccZ3, DecZ1, DecZ2, and DecZ3 were revealed to be higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches. The second half of the official matches revealed higher values for total duration compared to friendly matches (p < 0.05, moderate effect size). In conclusion, this study observed higher values of metabolic power in friendly matches compared to official matches. AccZ3, DecZ1, DecZ2, and DecZ3 were higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches.
- Comparison of running distance variables and body load in competitions based on their results: a full‐season study of professional soccer playersPublication . Nobari, Hadi; Oliveira, Rafael; Brito, João Paulo; Pérez‐Gómez, José; Clemente, Filipe ManuelAbstract: The aims of this study were to compare the external workload in win, draw and defeat matches and to compare first and second halves in the Iranian Premier League. Observations on individual match performance measures were undertaken on thirteen outfield players (age, 28.6 ± 2.7 years; height, 182.1 ± 8.6 cm; body mass, 75.3 ± 8.2 kg; BMI, 22.6 ± 0.7 kg/m2) competing in the Iranian Premier League. High‐speed activities selected for analysis included total duration of matches, total distance, average speed, high‐speed running distance, sprint distance, maximal speed and GPS‐derived body load data. In general, there were higher workloads in win matches when compared with draw or defeat for all variables; higher workloads in the first halves of win and draw matches; higher total distance, high‐speed running distance and body load in the second half in defeat matches. Specifically, lower average speed was found in matches with a win than with draw or defeat (p < 0.05). Sprint distance was higher in the first half of win than defeat matches and high‐speed running distance was lower in draw than defeat matches (all, p < 0.05). In addition, first half presented higher values for all variables, regardless of the match result. Specifically, high‐speed running distance was higher in the first half of matches with a win (p = 0.08) and total distance was higher in the first half of matches with a draw (p = 0.012). In conclusion, match result influences the external workload demands and must be considered in subsequent training sessions and matches.