Jaime Fernandez-Fernandez
Ruhr University Bochum
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Jaime Fernandez-Fernandez.
British Journal of Sports Medicine | 2007
Alberto Mendez-Villanueva; Jaime Fernandez-Fernandez; David Bishop; Benjamín Fernández-García; Nicolás Terrados
Objective: To examine the game characteristics and physiological (ie, blood lactate concentration) and perceptual (ie, rating of perceived exertion, RPE) responses during actual tennis competition in professional performers. Methods: Eight trained and internationally ranked (Association of Tennis Professionals rankings) male tennis players were studied during singles matches (best of three sets) played on an outdoor clay court surface during a professional, invitational tournament. Blood lactate concentrations (n = 53) and RPE (n = 113) were determined at selected changeovers during the game. The variables describing the characteristics of the matches, (a) duration of rallies (DRs); (b) rest time (RT); (c) effective playing time (EPT); and (d) shots per rally (SR), were determined from video recordings. Results: The mean (SD) values for the match-play activity variables were DR 7.5 (7.3) s, RT 16.2 (5.2) s, EPT 21.5 (4.9%), SR 2.7 (2.2) shots. Average blood lactate concentration and RPE values were 3.8 (2.0) mmol/l and 13 (2). Blood lactate concentrations and RPE values were significantly higher (p<0.01) in service games than in receiving games. Both blood lactate concentration and RPE values were significantly correlated with SR and DR (r = 0.80 to 0.28; p<0.001). Conclusions: Blood lactate concentrations and RPE were found to be influenced by the characteristics of the match and the playing situation (ie, serving or returning). These specific situations might be used to alter the overload training stimulus during tennis on-court practice.
British Journal of Sports Medicine | 2007
Jaime Fernandez-Fernandez; Alberto Mendez-Villanueva; Benjamín Fernández-García; Nicolás Terrados
Objective: To assess physiological load in conjunction with individual patterns of match-play activity in junior female tennis players during actual singles tennis competition. Methods: Eight elite junior female tennis players (n = 8; mean (SD) age, 17.3 (1.9) years) took part in a 2 day invitational tournament. Activity pattern analysis was performed during competitive matches. Heart rate and blood lactate concentrations were measured during selected changeovers breaks in play. Results: The activity profile of junior female players were: rally duration, (mean (SD)) 8.2 (5.2) s; rest time between rallies, 17.7 (6.5) s; effective playing time, 21.9 (3.8)%; strokes per rally, 2.7 (1.7); changes of direction per rally, 2.3 (1.4). The mean (SD) heart rate and blood lactate concentration recorded during the matches were 161 (5) beats/min and 2.0 (0.8) mmol/litre. Heart rate and blood lactate concentration values were influenced by the characteristics of the match and mean (SD) heart rate was significantly higher (p = 0.004) during service games (166 (15.4) beats/min) than in return games (156 (19.6) beats/min), while blood lactate concentrations were not significantly different (p = 0.83) between service (2.3 (0.6) mmol/litre) and return games (2.3 (0.9) mmol/litre). We found a significant (p<0.05) positive relationship between rally duration, strokes per rally, changes of direction and blood lactate and heart rate responses, with stronger correlations when the players were serving. Conclusions: The physiological (ie, blood lactate and heart rate) responses associated with match play were influenced by the characteristics of the match (rally duration, strokes per rally and changes of direction), with higher heart rate on service position. Training programs should reflect these demands placed on female players during competitive match play.
Journal of Strength and Conditioning Research | 2012
Jaime Fernandez-Fernandez; Rico Zimek; Thimo Wiewelhove; Alexander Ferrauti
Fernandez-Fernandez, J, Zimek, R, Wiewelhove, T, and Ferrauti, A. High-intensity interval training vs. repeated-sprint training in tennis. J Strength Cond Res 26(1): 53–62, 2012—The aim of this study was to compare the effects of high-intensity interval training (HIIT) and repeated-sprint training (RST) on aerobic fitness, tennis-specific endurance, linear and repeated-sprint ability (RSA), and jumping ability. Thirty-one competitive male tennis players took part in a training intervention of 6 weeks. The players were matched into 3 groups, HIIT (n = 11), RST (n = 12), or control group (CON, n = 9). The results showed significant time × intervention interactions for &OV0312;O2peak, with a significant increase in the &OV0312;O2peak level of 6.0% in HIIT (p = 0.008) and 4.9% in RST (p = 0.010), whereas no changes occurred in CON. However, the following differences were found between the intervention groups: The HIIT-induced greater improvements in tennis-specific endurance (HIIT 28.9% vs. RST 14.5%; p < 0.05) and RST led to a significant improvement in RSA (i.e., reduction in the mean sprint time of 3.8%; p < 0.05). Neither training strategy induced any effects on jumping and sprinting abilities. Both training interventions showed similar improvements in general aerobic fitness. Also, the present results suggest that RST represents a time-efficient stimulus for a simultaneous improvement of general and tennis-specific aerobic fitness as well for RSA.
Journal of Sports Sciences | 2011
Alexander Ferrauti; Vanessa Kinner; Jaime Fernandez-Fernandez
Abstract This study was conducted to validate and evaluate the “Hit & Turn Tennis Test”, an acoustically progressive on-court endurance test for tennis players. Ninety-eight competitive tennis players (53 males, 45 females) of different age groups participated in the study. For validation, the adult male players completed three Hit & Turn tests, one on a clay court and two on a carpet surface, a tennis-specific ball machine test and an incremental treadmill run in a randomized order. A stronger correlation between maximal performance (r = 0.81, P < 0.01) and maximal oxygen uptake (r = 0.96, P < 0.01) was observed between the Hit & Turn test and the ball machine test, than between the Hit & Turn test and the treadmill test. For test–retest, we found a significant correlation between maximal performance on the same (r = 0.83, P < 0.01) and on different surfaces (r = 0.74, P < 0.01). During test evaluation, maximal performance was higher in males than in females (P < 0.01) and increased by consecutive age group in boys (P < 0.01) but not in girls (P = 0.97). In conclusion, Hit & Turn maximum test performance can be recommended as a valid and reliable indicator for tennis-specific endurance.
Journal of Sports Sciences | 2008
Jaime Fernandez-Fernandez; David Sanz-Rivas; Benjamín Fernández-García; Alberto Mendez-Villanueva
Abstract The aim of this study was to determine the match activity and physiological demands of womens tennis during a 3-day clay-court tennis tournament. The activity profile of eight players was determined by filming each competitive match with video cameras. Metabolic-perceptual measurements–blood samples and individual ratings of perceived exertion (RPE)–were taken while the players were sitting during permitted changeover breaks in play. The activity profile of the players was as follows: strokes per rally, 2.5 ± 1.6; rally duration, 7.2 ± 5.2 s; rest time between rallies, 15.5 ± 7.3 s; effective playing time, 21.6 ± 6.1%; work-to-rest ratio, 1:2.1. Blood lactate concentration [2.2 ± 0.9 mmol · l−1 (n = 50) vs. 2.2 ± 0.7 mmol · l−1 (n = 48)] and RPE values [12.2 ± 2.4 (n = 57) vs. 12 ± 2.3 (n = 57)] were not significantly different (P = 0.65–0.78) between service and return games. The results highlight the importance of taking these factors (i.e. activity patterns and physiological profile) into account when planning training strategies for competitive females players. As such, tennis training regimes should be adapted to the specific demands imposed by match-play in female players on a clay-court surface.
Journal of Strength and Conditioning Research | 2010
Alexander Ferrauti; Matthias Bergermann; Jaime Fernandez-Fernandez
Ferrauti, A, Bergermann, M, and Fernandez-Fernandez, J. Effects of a concurrent strength and endurance training on running performance and running economy in recreational marathon runners. J Strength Cond Res 24(10): 2770-2778, 2010-The purpose of this study was to investigate the effects of a concurrent strength and endurance training program on running performance and running economy of middle-aged runners during their marathon preparation. Twenty-two (8 women and 14 men) recreational runners (mean ± SD: age 40.0 ± 11.7 years; body mass index 22.6 ± 2.1 kg·m−2) were separated into 2 groups (n = 11; combined endurance running and strength training program [ES]: 9 men, 2 women and endurance running [E]: 7 men, and 4 women). Both completed an 8-week intervention period that consisted of either endurance training (E: 276 ± 108 minute running per week) or a combined endurance and strength training program (ES: 240 ± 121-minute running plus 2 strength training sessions per week [120 minutes]). Strength training was focused on trunk (strength endurance program) and leg muscles (high-intensity program). Before and after the intervention, subjects completed an incremental treadmill run and maximal isometric strength tests. The initial values for &OV0312;o2peak (ES: 52.0 ± 6.1 vs. E: 51.1 ± 7.5 ml·kg−1·min−1) and anaerobic threshold (ES: 3.5 ± 0.4 vs. E: 3.4 ± 0.5 m·s−1) were identical in both groups. A significant time × intervention effect was found for maximal isometric force of knee extension (ES: from 4.6 ± 1.4 to 6.2 ± 1.0 N·kg−1, p < 0.01), whereas no changes in body mass occurred. No significant differences between the groups and no significant interaction (time × intervention) were found for &OV0312;o2 (absolute and relative to &OV0312;o2peak) at defined marathon running velocities (2.4 and 2.8 m·s−1) and submaximal blood lactate thresholds (2.0, 3.0, and 4.0 mmol·L−1). Stride length and stride frequency also remained unchanged. The results suggest no benefits of an 8-week concurrent strength training for running economy and coordination of recreational marathon runners despite a clear improvement in leg strength, maybe because of an insufficient sample size or a short intervention period.
British Journal of Sports Medicine | 2007
Alberto Mendez-Villanueva; Jaime Fernandez-Fernandez; David Bishop
This review addresses metabolic, neural, mechanical and thermal alterations during tennis match play with special focus on associations with fatigue. Several studies have provided a link between fatigue and the impairment of tennis skills proficiency. A tennis player’s ability to maintain skilled on-court performance and/or optimal muscle function during a demanding match can be compromised as a result of several homeostatic perturbations, for example hypoglycaemia, muscle damage and hyperthermia. Accordingly, an important physiological requirement to succeed at competitive level might be the player’s ability to resist fatigue. However, research evidence on this topic is limited and it is unclear to what extent players experience fatigue during high-level tennis match play and what the physiological mechanisms are that are likely to contribute to the deterioration in performance.
British Journal of Sports Medicine | 2014
Jaime Fernandez-Fernandez; Alexander Ulbricht; Alexander Ferrauti
In tennis, sport-specific technical skills are predominant factors, although a complex profile of physical performance factors is also required. The fitness test batteries assist in examining tennis players’ capabilities for performance at different levels in the laboratory as well as in the field, in the junior or elite level. While laboratory tests can be, and are, used to evaluate basic performance characteristics of athletes in most individual sports, in a more specific approach, field-based methods are better suited to the demands of complex intermittent sports like tennis. A regular test battery performed at different periods of the year allows to obtain an individuals performance profile, as well as the ability to prescribe individual training interventions. Thus, the aim of the present review was to describe and evaluate the different physical tests recommended and used by practitioners, sports scientists and institutions (national tennis federations).
Journal of Strength and Conditioning Research | 2010
Alberto Mendez-Villanueva; Jaime Fernandez-Fernandez; David Bishop; Benjamín Fernández-García
Mendez-Villanueva, A, Fernandez-Fernández, J, Bishop, D, and Fernandez-Garcia, B. Ratings of perceived exertion-lactate association during actual singles tennis match play. J Strength Cond Res 24(1): 165-170, 2010-To examine the relationship between metabolic (i.e., blood lactate concentration) and perceptual (ratings of perceived exertion, RPE) responses and their association with variables describing the characteristics of the singles tennis match play. Eight trained and internationally ranked (Association of Tennis Professionals rankings) male tennis players were studied during singles matches (best of 3 sets) played on an outdoor clay court surface during a professional invitational tournament. Ratings of perceived exertion and blood lactate concentrations were determined at selected changeovers during the game. The variables describing the characteristics of the matches, (a) duration of rallies (DR), (b) rest time, (c) effective playing time, and (d) strokes per rally (SR), were determined from video recordings. Significant correlations (r = 0.57-0.48; p < 0.01) were found for RPE-blood lactate responses during the games. Both RPE and blood lactate concentration values were significantly correlated with SR and DR (r = 0.80-0.61; p < 0.001) in service games. Average RPE was significantly higher (p < 0.05) following service games (13.5 ± 1.9; n = 24) than following receiving games (12.2 ± 2.0; n = 22). Mean blood lactate concentrations were significantly higher (p < 0.05) following service games (4.4 ± 2.4 mmol·L−1; n = 24) than following receiving games (3.0 ± 1.3 mmol·L−1; n = 22). These results indicate that monitoring RPE may be a useful technique for regulating on-court tennis training intensity. Moreover, blood lactate may mediate the relation between RPE and tennis match play intensity.
Journal of Strength and Conditioning Research | 2014
Ernest Baiget; Jaime Fernandez-Fernandez; Xavier Iglesias; Lisímaco Vallejo; Ferran A. Rodríguez
Abstract Baiget, E, Fernández-Fernández, J, Iglesias, X, Vallejo, L, and Rodríguez, FA. On-court endurance and performance testing in competitive male tennis players. J Strength Cond Res 28(1): 256–264, 2014—The aims of this study were (a) to establish a specific endurance test procedure for competitive tennis players, combining performance, physiological and technical parameters and (b) to determine the relationship between these parameters and their competitive levels. Thirty-eight competitive male tennis players (age, 18.2 ± 1.3 years; height, 180 ± 0.08 cm; body mass, 72.7 ± 8.6 kg; mean ± SD) performed a specific endurance field test. Performance (level achieved), physiological (heart rate, maximum oxygen uptake (V[Combining Dot Above]O2max), and ventilatory thresholds (VT1, VT2), and technical parameters (technical effectiveness [TE]) were assessed. Bivariate and multivariate models for predicting performance level were developed. Technical effectiveness was 63.1 ± 9.1%, with 3 identified phases throughout the test (adaptation, maximum effectiveness, and steady decline). Low to moderate correlations were found between performance (final stage), physiological (VT1, VT2) and TE, and competitive performance (r = 0.35–0.61; p = 0.038–0.000). Technical effectiveness explained 37% of variability in competitive performance (r = 0.61; p = 0.001). Using TE combined with VT2 or predictability increased explaining approximately 55% (p < 0.05) of the variance in competitive performance. The present study showed the usefulness of a field test including physiological and performance elements in high-caliber tennis players, and VT2 values combined with TE were good predictors of tennis performance.