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Sex differences in aerobic fitness in top-class soccer referees
No full textCastagna, C, Bizzini, M, D'Ottavio, S, and Araújo Póvoas, SC. Sex differences in aerobic fitness in top-class soccer referees. J Strength Cond Res 32(11): 3216-3221, 2018-The aim of this study was to assess the aerobic-fitness differences between male and female top-class soccer field referees (FRs). This with the purpose to provide cutoff values useful for training prescription in female FRs. Forty female top-class FRs (age 34.18 ± 3.50 years and 5 ± 3.9 years international refereeing experience) and 52 male FRs (age 38.4 ± 3.3 years and 5 ± 3.5 years international refereeing experience) candidates in the preliminary open list developed by the FIFA Refereeing Department for the 2014 and 2015 World Cup Tournaments, participated in the study. The FRs were tested for aerobic fitness under laboratory conditions with a progressive speed treadmill test until exhaustion. Female FRs showed to possess, on average, lower (large effect) levels of aerobic fitness and performance compared with their male counterparts. The female FRs' V[Combining Dot Above]O2max (48.1 ± 4.4 ml·kg·min) was 7% (large effect) lower than the male FRs (51.9 ml·kg·min). Peak treadmill speed was 11% lower (large effect) in female FRs (16.27 ± 0.94 vs. 14.64 ± 0.96 km·h). The receiver operating characteristic curve analysis enabled cutoff values (47.8 ml·kg·min for V[Combining Dot Above]O2max) that may be used as preliminary cues to guide physiological selection and training prescription in female FRs aiming to officiate male-soccer matches. Only 2.5% of the female FRs showed V[Combining Dot Above]O2max higher than the mean values of male FRs when using the scaled notation (0.68). Female FRs aiming to officiate male competitions should consider training intensities at anaerobic threshold speed (13 km·h, 95% heart rate max) when developing aerobic fitness. Given the very large sex differences in aerobic performance, strength/power training should be proposed to perspective female top-class FRs
Effetti di differenti metodologie di allenamento di forza e potenza aerobica sui livelli di Velocità Massimale Aerobica (VMA) forniti dal test di Leger
No full textPhysiological Load Imposed On Elite Soccer Referees During Actual Match Play.
No full textAbstract
BACKGROUND:
The aim of this study as to describe the work-rate profile and cardiovascular stress of Italian high level soccer referees (n = 18). METHODS.
EXPERIMENTAL DESIGN:
The referees were examined during official games of the 1992-1993 first division Italian championship (serie A).
PARTICIPANTS:
subjects were all experienced top level referees enrolled in the CAN (Commissione Arbitri Nazionali) and thus officiating in the serie A e B Italian championships. Mean age of the referees considered here was 37.5 +/- 2.14 years.
MEASURES:
heart rates were monitored by short-range radio telemetry. Match analysis was performed with methodologies similar to that reported by Ohashi et al. (1988).
RESULTS:
Average match distance was 11376 +/- 1600 m (7818-13063) and no overall differences were observed between halves (p > 0.05). Nevertheless less distances were covered running backward and side-wards during the second half compared to the first half (p < 0.05). Referees, on average, covered 41.7% of the whole match distance at speeds faster than 13.1 km x h(-1). Heart rates attained 89.1% of the estimated maximal over the duration of a full game and no difference was observed between halves (p = 0.72). Mean heart rates of the first 15 min of play were lower than the other two sections of the first half (p < 0.05).
CONCLUSIONS:
Match analysis revealed the intermittent nature of the referees' activities. Their intensity varied from situation to situation, frequently reaching near maximal intensity. However, sprint bouts never lasted for more than few seconds (2-4 sec). Top level soccer refereeing places high physiological demands on the official thus specific training and fitness assessment are needed
Relation between maximal aerobic power and the ability to repeat sprints in young basketball players
No full textCastagna, C., V. Manzi, S. D'Ottavio, G. Annino,E. Padua, and D. Bishop. Relation between maximal aerobic power and the ability to repeat sprints in young basketball players. J. Strength Cond. Res. 21(4):1172-1176. 2007.-The aim of this study was to examine the effects of maximal aerobic power (&Vdot;o(2)peak) level on the ability to repeat sprints (calculated as performance decrement and total sprinting time) in young basketball players. Subjects were 18 junior, well-trained basketball players (age, 16.8 +/- 1.2 years; height, 181.3 +/- 5.7 cm; body mass, 73 +/- 10 kg; &Vdot;o(2)peak, 59.6 +/- 6.9 ml.kg(-1).min(-1)). Match analysis and time-motion analysis of competitive basketball games was used to devise a basketball-specific repeated-sprint ability protocol consisting of ten 15-m shuttle run sprints with 30 s of passive recovery. Pre, post, and post plus 3-minute blood lactate concentrations were 2.5 +/- 0.7, 13.6 +/- 3.1, and 14.2 +/- 3.5 mmol.L(-1), respectively. The mean fatigue index (FI) value was 3.4 +/- 2.3\% (range, 1.1-9.1\%). No significant correlations were found between &Vdot;o(2)peak and either FI or total sprint time. A negative correlation (r = -0.75, p = 0.01) was found between first-sprint time and FI. The results of this study showed that &Vdot;o(2)peak is not a predictor of repeated-sprint ability in young basketball players. The high blood lactate concentrations found at the end of the repeated-sprint ability protocol suggest its use for building lactate tolerance in conditioned basketball players
Aerobic Fitness in Top-Class Soccer Referees
No full textCastagna, C, Bizzini, M, Araújo Póvoas, SC, Schenk, K, Büsser, G, and D'Ottavio, S. Aerobic fitness in top-class soccer referees. J Strength Cond Res 33(11): 3098-3104, 2019-The aim of this study was to examine the aerobic fitness status of top-class male soccer officials using a cross-sectional design and known population group constructs. Fifty-two field referees (FRs, age 38.4 ± 3.3 years; height 181 ± 5.6 cm; body mass 76.8 ± 6.8 kg; body mass index [BMI] 23.4 ± 1.7 kg·m; body fat 20.4 ± 3.6%; and international refereeing experience 5 ± 3.5 years) and 104 assistant referees (ARs, age 37.8 ± 4.1 years; height 176.9 ± 7.5 cm; body mass 72.1 ± 7.4 kg; BMI 23 ± 1.6 kg·m; body fat 19.2 ± 3.6%; and international refereeing experience 7 ± 3.8 years) from 53 National Football Associations worldwide, and candidates of the preliminary open-list developed by the FIFA Refereeing Department for the 2014 World Cup Final Tournament, were tested for aerobic fitness in laboratory conditions with a progressive speed treadmill test to exhaustion. Large (+8.54%, d = 0.8) and small (+3.1%, d = 0.3) differences in absolute (L·min) and relative (ml·kg·min) VO2max were found between FR and AR, respectively. Trivial differences (d = 0.07) were shown in running economy (RE) (6 minutes at 8 km·h) between AR and FR. Using the scaling notation (b = 0.64), medium and significant differences were found between match officials for VO2max and RE (FR > AR; d = 0.6 and 0.67, respectively). Using receiver operating characteristic curve statistics, cutoff values of 3.93 L·min and 50.6 ml·kg·min were detected in absolute and relative VO2max for the FR and the AR (FR > AR), respectively. The FR showed superior aerobic fitness compared with AR. Training prescription should consider intensities at anaerobic threshold speed (14 km·h, 91% heart rate max) when aerobic fitness development is the aim in elite officials
Reliability characteristics and applicability of a repeated sprint ability test in male young soccer players
Full text linkCastagna, C, Lorenzo, F, Krustrup, P, Fernandes-da-Silva, J, Po ́ voas, SCA, Bernardini, A, and D’Ottavio, S. Reliability charac- teristics and applicability of a repeated sprint ability test in male young soccer players. J Strength Cond Res XX(X): 000–000, 2017—The aim of this study was to examine the usefulness and reliability characteristics of a repeated sprint ability test consider- ing 5 line sprints of 30 m interspersed with 30 seconds of active recovery in nonelite, outfield, young, male soccer players. Twenty- six (age, 14.9 6 1.2 years; height, 1.72 6 0.12 cm; body mass, 62.2 6 5.1 kg) players were tested 48 hours and 7 days apart for 5 3 30-m performance over 5 trials (T1–T5). Short-term (T1–T2) and long-term (T1–T3–T4–T5) reliabilities were assessed with intraclass correlation coefficient (ICC) and with typical error for measurement (TEM). Short- and long-term reliability ICCs and TEMs for total sprint time and best sprint performance were nearly perfect and satisfactory, respectively. Usefulness (as smallest worthwhile change and TEM ratio) resulted acceptable (i.e., = 1) and good (i.e., .1) for total sprint time and best sprint perfor- mance, respectively. The present study revealed that the 5 3 30-m sprint test is a reliable field test in short and long terms when the sum of sprint times and the best sprint performance are considered as outcome variables. Sprint performance decre- ments variables showed large variability across trials
Development and implementation of a multi-physics high fidelity model of the TRIGA mark II reactor
No full textIn this paper, we develop, verify and validate a high fidelity multi-physics model of the TRIGA Mark II reactor of the University of Pavia, based on the coupling between the Serpent Monte Carlo code for neutronics and the OpenFOAM CFD toolkit for thermal-hydraulics. We get a realistic and accurate characterization of the reactor at the steady state condition for the first criticality configurations at fresh fuel. We validate the neutronics and thermal-hydraulics results with the available experimental data for criticality parameters and fuel temperature. In addition, we carry out code-to-code comparisons with the previous state-of-the-art multi-physics model and data in literature for power profiles, temperature and velocity fields. We also observe how the model has the powerful capability to characterise the effects of the control rods movements on the local fuel temperature. Future perspectives of this work include its employment to study transient analysis and complex CFD phenomena, as the natural circulation and fluid instabilities
Ecological and Construct Validity of a Repeated Sprint Test in Male Youth Soccer Players
No full textFernandes-Da-Silva, J, Castagna, C, Teixeira, AS, Carminatti, LJ, Francini, L, Póvoas, SCA, and Antonacci Guglielmo, LG. Ecological and construct validity of a repeated sprint test in male youth soccer players. J Strength Cond Res XX(X): 000-000, 2019-This study aimed to examine the relationship between a repeated sprint ability (RSA) test (5 bouts of 30-m sprints interspersed by 30 seconds of recovery) and match-related physical performance in male youth soccer players. Although 60 outfield players were evaluated, only data from players who participated in the full matches (n = 39) were retained (8 central defenders, 7 external defenders, 8 central midfielders, 8 external midfielders, and 8 forwards). To verify the ecological validity of this RSA protocol, the association between the best (RSAbest) and mean (RSAmean) sprint time in the 5 × 30-m and physical match performance during friendly youth soccer games was examined. Physical match demands were assessed using global positioning system technology (10 Hz) considering distance covered in selected arbitrary speed categories. The absolute speed thresholds were the same for all the players. Players were categorized into 2 groups based on the 5 × 30-m performance: RSAmean times below (i.e., faster) and above (i.e., slower) the median value. Players with faster RSAmean times covered significantly more distance sprinting during friendly matches (606 ± 204 m, +47.0%; t = 4.953; effect size = 1.88, 1.24; 2.52, p ≤ 0.001) compared to their slower counterparts (322 ± 145 m). A large negative correlation (r = -0.63, -0.77; -0.44, p ≤ 0.001) was found between RSAbest time (4.59 ± 0.27 seconds) and match sprint distance (457 ± 229 m). Likewise, RSAmean time (4.76 ± 0.25 seconds) was also largely associated (r = -0.60, -0.75; -0.39; p ≤ 0.001) with in-game sprinting performance. The results of this study provided evidence to support the construct and ecological validity of the 5 × 30-m protocol in male youth soccer players. Furthermore, differences in 5 × 30-m performance explained the amount of sprinting activity performed during the match
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