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Purpose: To investigate the optimal pretaper duration on match running performance in a professional soccer team. Methods: The training load was monitored during daily training sessions and matches during 2 seasons according to different periodization strategies. Matches' running distances were collected using match analysis system. The data were analyzed in 3 types of mesocycle blocks of 5 (M5), 4 (M4), and 3 weeks (M3), concludes all of them by 1 taper week. Results: Significant decreases in the training load during the taper weeks compared to standard weeks were observed in 3 types of mesocycle blocks (d ≥ 5; P <.01). An increase in overall match running performance was observed in matches played after the taper weeks compared to matches played after the standard weeks during M4 for all speed ranges (d ≥ 1.3; P <.05). The increase was only observed in low-intensity running (d = 1.3; P <.04) and total distance, low-intensity running, and intense running (d ≥ 1.3; P <.05) in M5 and M3, respectively. Match running performance following the taper weeks between the 3 different mesocycle durations was significantly higher in M4 for the number of high-speed running, sprinting, and high-intensity running (P <.05). The greatest enhancement of match running performance was observed at M4 when the training load was decreased by approximately 18% during the tapering period. Conclusion: This study suggests that a period of 3 standard weeks of training followed by 1 taper week is the optimal taper strategy when compared to different pretaper durations. [ABSTRACT FROM AUTHOR]

To compare the effects of explosive strength (ExpS) vs. repeated shuttle sprint (RS) training on repeated sprint ability (RSA) in young elite soccer players, 15 elite male adolescents (14.5 [+ or -] 0.5 years) performed, in addition to their soccer training program, RS (n = 7) or ExpS (n = 8) training once a week for a total of 10 weeks. RS training consisted of 2-3 sets of 5-6 x 15-to 20-m repeated shuttle sprints interspersed with 14 seconds of passive or 23 seconds of active recovery ([approximately equal to] 2 m x [s.sup.-1]); ExpS training consisted of 4-6 series of 4-6 exercises (e.g., maximal unilateral countermovement jumps (CMJs), calf and squat plyometric jumps, and short sprints). Before and after training, performance was assessed by 10 and 30 m (10 and 30 m) sprint times, best ([RSA.sub.best]) and mean ([RSA.sub.mean] ) times on a repeated shuttle sprint ability test, a CMJ, and a hopping (Hop) test. After training, except for 10 m (p = 0.22), all performances were significantly improved in both groups (all p's < 0.05). Relative changes in 30 m (-2.1 [+ or -] 2.0%) were similar for both groups (p = 0.45). RS training induced greater improvement in [RSA.sub.best] (-2.90 [+ or -] 2.1 vs. -0.08 [+ or -] 3.3%, p = 0.04) and tended to enhance [RSA.sub.mean] more (-2.61 [+ or -] 2.8 vs. -0.75 [+ or -] 2.5%, p= 0.10, effect size [ES] =0.70) than ExpS. In contrast, ExpS tended to induce greater improvements in CMJ (14.8 [+ or -] 7.7 vs. 6.8 [+ or -] 3.7%, p = 0.02) and Hop height (27.5 [+ or -] 19.2 vs. 13.5 [+ or -] 13.2%, p = 0.08, ES = 0.9) compared with RS. Improvements in the repeated shuttle sprint test were only observed after RS training, whereas CMJ height was only increased after ExpS. Because RS and ExpS were equally efficient at enhancing maximal sprinting speed, RS training-induced improvements in RSA were likely more related to progresses in the ability to change direction. KEY WORDS football, team sports, multiple sprint work, adolescent training

J Strength Cond Res 24(1): 165-1 70, 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 [+ or -] 1.9; n = 24) than following receiving games (12.2 [+ or -] 2.0; n = 22). Mean blood lactate concentrations were significantly higher (p < 0.05) following service games (4.4 [+ or -] 2.4 mmol x [L.sup.-1]; n = 24) than following receiving games (3.0 [+ or -] 1.3 mmol x [L.sup.-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. KEY WORDS tennis competition play, blood lactate concentration, rating of perceived exertion

J Strength Cond Res 24(1): 135-139, 2010--No previous study has examined the reliability of competitive performance in a subjective (i.e., externally judged) sport such as surfboard riding (i.e., surfing). This reliability is important for the athletes' competitive success prospects and for their support crew interested in strategies or factors that might influence performance. We have therefore determined the typical variation in competitive performance of elite surfers. We obtained official scores (points) for the 11 competitions of the World Championship Tour (WCT). We analyzed 46 male surfers who entered 6 or more such events held in 1 competitive season. To further explore the variability of competitive performance, a separate analysis was performed on official performance points for 182 male surfers who competed on 3 consecutive events within the World Qualifying Series (WQS). Our measure of variability was the typical error (i.e., within-subject variation) expressed as a Cohen effect size (ES) of log-transformed final scores obtained for the surfers after finishing each event. Performance scores in surfing competition showed moderate to large variability. For the 11 WCT events and the 3 WQS events, the ES ranged from 0.72 to 1.01 (n = 46) and from 0.61 to 1.04 (n = 182), respectively. In conclusion, surfers showed much larger variability in performance than previously reported for sports such as running, swimming, or weightlifting. Thus, competition outcomes are largely unpredictable. Considering this large variability in competitive performance, a practitioner monitoring an individual athlete will have little chances of noticing small to moderate changes in competitive performance between consecutive events. Several competitions in a row appear to be needed for tracking the smallest worthwhile performance changes in competition scores as a result of training or other interventions. KEY WORDS elite athletes, reliability, surfing, reproducibility of competitive performance

The aim of the study was to examine whether differences in playing level influence the activity profile and physiological demands of advanced and recreational veteran men's tennis players during an hour of tennis match play. Ten advanced (International Tennis Number [ITN] 3-5, 45.3 [+ or -] 5.1 years) and 10 recreational (ITN 7-9, 44.8 [+ or -] 4.7 years) veteran men's tennis players participated in 4 experimental sessions: (1) an ITN on-court assessment, (2) a laboratory incremental treadmill test, (3) an hour of simulated tennis match play, and (4) 30 minutes of tennis match play using a portable gas analyzer. Subjects' [??][O.sub.2] and heart rate (HR) were recorded by portable analyzers. Moreover, energy expenditure was evaluated by indirect calorimetry. Temporal structure and distance covered were determined from video recordings. Subjects' [??][O.sub.2] (24.5 [+ or -] 4.1 vs. 23.3 [+ or -] 3 ml x [kg.sup.-1] x [min.sup.-1]), HR (148.3 [+ or -] 11.5 vs. 149.8 [+ or -] 8.4 bpm), duration of rallies (DR) (6.3 [+ or -] 4.1 vs. 7.6 [+ or -] 5.5 seconds), and effective playing time (EPT) (21.7 [+ or -] 5.0 vs. 23.6 [+ or -] 5.4%), HR (148.3 [+ or -] 11.5 vs. 149.8 [+ or -] 8.4 bpm), and energy expenditure (263.1 [+ or -] 49.4 and 281.3 [+ or -] 61.8 kcal x [min.sup.-1]) during play did not differ significantly (p > 0.05) between advanced and recreational players. The advanced players covered significantly more meters than the recreational players during their 1 -hour tennis matches (mean [+ or -] SD: 3568.8 [+ or -] 532.2 vs. 3173.8 [+ or -] 226 m, p < 0.01) at lower running speeds. The results indicate that, independently of ability, tennis match play satisfies the American College of Sports Medicine recommendations for quantity and quality of exercise for the development and maintenance of cardiovascular fitness in healthy adults and seems to be a viable and highly popular mode of healthy activity. KEY WORDS energy expenditure, fitness, heart rate, racquet sports, oxygen uptake

The activity profile of men's competitive surfing was investigated during an international contest. Forty-two male surfers were filmed during 42 elimination heats. Surfers' activities were classified into 1 of 4 distinct categories (paddling, wave riding, stationary, and miscellaneous). The surfers were paddling and stationary 51% (25-70%) and 42% (23-72%) of the total time, respectively. Wave riding accounted for 4% (2-7%) of the total time, whereas miscellaneous activity accounted for the remaining 2% (0.1-6%) of the total time. The frequency (average number of motions in a heat) of each activity was 26 for paddling (15-37); 17 for stationary (10-26); 5 for wave riding (2-8); and 6 for miscellaneous activity (1-13). The mean duration lengths of the activities were 30.1 seconds (1-286 seconds), 37.7 seconds (1-413 seconds), 11.6 seconds (1-44 seconds), and 5 seconds (1-31 seconds) for paddling, stationary, wave riding, and miscellaneous activities, respectively. Most of the paddling bouts (-60%) were performed at time intervals of between 1 and 20 seconds. Approximately 50% (50.9%) of the rest intervals were between 1 and 20 seconds in duration. The results showed that surfing is an intermittent activity characterized by a large variability and random distribution of each parameter analyzed. This information can be used to assist in the development of fitness training programs and physiological testing for competitive surfers. Key Words. surfboard riding, time motion, arm paddling, wave riding

Purpose: To analyze the effects of 2 different eccentric-overload training (EOT) programs, using a rotational conical pulley, on functional performance in team-sport players. A traditional movement paradigm (ie, squat) including several sets of 1 bilateral and vertical movement was compared with a novel paradigm including a different exercise in each set of unilateral and multi-directional movements. Methods: Forty-eight amateur or semiprofessional team-sport players were randomly assigned to an EOT program including either the same bilateral vertical (CBV, n = 24) movement (squat) or different unilateral multidirectional (VUMD, n = 24) movements. Training programs consisted of 6 sets of 1 exercise (CBV) or 1 set of 6 exercises (VUMD) x 6-10 repetitions with 3 min of passive recovery between sets and exercises, biweekly for 8 wk. Functional-performance assessment included several change-of-direction (COD) tests, a 25-m linear-sprint test, unilateral multidirectional jumping tests (ie, lateral, horizontal, and vertical), and a bilateral vertical-jump test. Results: Within-group analysis showed substantial improvements in all tests in both groups, with VUMD showing more robust adaptations in pooled COD tests and lateral/horizontal jumping, whereas the opposite occurred in CBV respecting linear sprinting and vertical jumping. Between-groups analyses showed substantially better results in lateral jumps (ES = 0.21), left-leg horizontal jump (ES = 0.35), and 10-m COD with right leg (ES = 0.42) in VUMD than in CBV. In contrast, left-leg countermovement jump (ES = 0.26) was possibly better in CBV than in VUMD. Conclusions: Eight weeks of EOT induced substantial improvements in functional-performance tests, although the force-vector application may play a key role to develop different and specific functional adaptations. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the kinematics and kinetics (force, velocity, and acceleration) and blood lactate concentration with the VersaPulley (VP) device in comparison with free-weight (FW) exercise at a similar external load. Fifteen rugby players randomly performed 2 training sessions of 6 sets of 6 repetitions with 20 s of recovery between sets of the high-pull exercise with the VP and the FW. The training sessions were separated by 72 h. Barbell displacement (cm), peak velocity (m/s), peak acceleration (m/s²), mean propulsive velocity (m/s), mean propulsive acceleration (m/s²), propulsive phase (%), and mean and maximal force (N) were continuously recorded during each repetition. Blood lactate concentration was measured after each training session (end) and 3 min and 5 min later. Barbell displacement (+4.8%, small ES), peak velocity (+4.5% small ES), mean propulsive acceleration (+8.8%, small ES), and eccentric force (+26.7, large ES) were substantially higher with VP than with FW. Blood lactate concentration was also greater after the VP exercise (end +32.9%, 3 min later +36%, 5 min later +33.8%; large ES). Maximal concentric force was substantially higher with FW than VP during the 6th set (+6.4%, small ES). In the cohort and exercise investigated in the current study, VP training can be considered an efficient training device to induce an accentuated eccentric overload and augmented metabolic demands (ie, blood lactate concentration). [ABSTRACT FROM AUTHOR]

Purpose: To compare the effects of unilateral and bilateral resistance training on single-leg power output, between-limbs imbalance (BLI), bilateral deficit (BLD), change of direction (COD), and linear sprinting and jumping performance in young elite basketball players. Methods: Twenty-two young (U-16-U-19) male basketball players were randomly assigned either to an exclusive unilateral (UNI) (n = 11) or a bilateral (BIL) (n = 11) resistance-training group during a 6-wk period. Both groups training consisted of 3 unilateral or bilateral 90° back-squat sets. A postdetermined number of repetitions was set until power output dropped to <10% of maximum power (MP) output. In addition, both groups performed 2 sets of 5 unilateral or bilateral drop jumps and 2 sets of 5 unilateral or bilateral countermovement jumps (CMJ). Pre- and posttraining, performance was assessed by an incremental bilateral and unilateral squat-load test, a multiple-COD test (V-cut test), a 15-m-sprint test (7.5 + 7.5 m) with one 180° COD performed with both right (180° RCOD) and left (180° LCOD) legs, a 25-m-sprint test (5- and 15-m split time), and a CMJ test. Results: Within-group analyses showed substantial improvements in 180° RCOD, bilateral and unilateral MP, 25-m-sprint test, and CMJ in both groups. Between-groups analyses showed substantially better results in 180° LCOD, MP with right and left legs, BLI, and BLD in UNI than in BIL. Conclusions: Both training programs substantially improved most of the physical-fitness tests, but only UNI reduced between-limbs asymmetry and achieved greater enhancements in actions that mostly required applying force unilaterally in basketball players. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of a low-volume repeated-power-ability (RPA) training program on repeated-sprint and change-of-direction (COD) ability and functional jumping performance. Methods: Twenty-two male elite young basketball players (age 16.2 ± 1.2 y, height 190.0 ± 10.0 cm, body mass 82.9 ± 10.1 kg) were randomly assigned either to an RPA-training group (n = 11) or a control group (n = 11). RPA training consisted of leg-press exercise, twice a week for 6 wk, of 1 or 2 blocks of 5 sets x 5 repetitions with 20 s of passive recovery between sets and 3 min between blocks with the load that maximized power output. Before and after training, performance was assessed by a repeated-sprint-ability (RSA) test, a repeated-COD-ability test, a hop for distance, and a drop jump followed by tests of a double unilateral hop with the right and left legs. Results: Within-group and between-groups differences showed substantial improvements in slowest (RSAs) and mean time (RSAm) on RSA; best, slowest and mean time on repeated-COD ability; and unilateral right and left hop in the RPA group in comparison with control. While best time on RSA showed no improvement in any group, there was a large relationship (r = .68, 90% CI .43;.84) between the relative decrement in RSAm and RSAs, suggesting better sprint maintenance with RPA training. The relative improvements in best and mean repeated-COD ability were very largely correlated (r = .89, 90% CI .77;.94). Conclusions: Six weeks of low-volume (4-14 min/wk) RPA training improved several physical-fitness tests in basketball players. [ABSTRACT FROM AUTHOR]

This study assessed the relationship between peak match speed (PMS) and maximal sprinting speed (MSS) in regard to age and playing positions. MSS and absolute PMS (PMSAbs) were collected from 180 male youth soccer players (U13-U17, 15.0 ± 1.2 y, 161.5 ± 9.2 cm, and 48.3 ± 8.7 kg). The fastest 10-m split over a 40-m sprint was used to determine MSS. PMSAbs was recorded using a global positioning system and was also expressed as a percentage of MSS (PMSRel). Sprint data were compared between age groups and between playing positions. Results showed that regardless of age and playing positions, faster players were likely to reach higher PMSAbs and possibly lower PMSRel. Despite a lower PMSAbs than in older groups (eg, 23.4 ± 1.8 vs 26.8 ± 1.9 km/h for U13 and U17, respectively, ES = 1.9 90%, confidence limits [1.6;2.1]), younger players reached a greater PMSRel (92.0% ± 6.3% vs. 87.2% ± 5.7% for U13 and U17, respectively, ES = -0.8 90% CL [-1.0;-0.5]). Playing position also affected PMSAbs and PMSRel, as strikers were likely to reach higher PMSAbs (eg, 27.0 ± 2.7 vs 23.6 ± 2.2 km/h for strikers and central midfielders, respectively, ES = 2.0 [1.7;2.2]) and PMSRel (eg, 93.6% ± 5.2% vs 85.3% ± 6.5% for strikers and central midfielders, respectively, ES = 1.0 [0.7;1.3]) than all other positions. The findings confirm that age and playing position affect the absolute and relative intensity of speed-related actions during matches. [ABSTRACT FROM AUTHOR]

Purpose: To describe the internal training load (ITL) of common training sessions performed during a typical week and to determine the relationships between different indicators of ITL commonly employed in professional football (soccer). Methods: Session-rating-of-perceived-exertion TL (sRPE-TL) and heart-rate- (HR) derived measurements of ITL as Edwards TL and Stagno training impulses (TRIMPMOD) were used in 9 players during 3 periods of the season. The relationships between them were analyzed in different training sessions during a typical week: skill drills/circuit training + small-sided games (SCT+SSGs), ball-possession games + technical-tactical exercises (BPG+TTE), tactical training (TT), and prematch activation (PMa). Results: HR values obtained during SCT+SSGs and BPG+TTE were substantially greater than those in the other 2 sessions, all the ITL markers and session duration were substantially greater in SCT+SSGs than in any other session, and all ITL measures in BPG+TTE were substantially greater than in TT and PMa sessions. Large relationships were found between HR >80% HRmax and HR >90% HRmax vs sRPE-TL during BPG+TTE and TT sessions (r = .61-.68). Very large relationships were found between Edwards TL and sRPE-TL and between TRIMPMOD and sRPE-TL in sessions with BPG+TTE and TT (r = .73-.87). Correlations between the different HR-based methods were always extremely large (r = .92-.98), and unclear correlations were observed for other relationships between variables. Conclusion: sRPE-TL provided variable-magnitude within-individual correlations with HR-derived measures of training intensity and load during different types of training sessions typically performed during a week in professional soccer. Caution should be applied when using RPE- or HR-derived measures of exercise intensity/load in soccer training interchangeably. [ABSTRACT FROM AUTHOR]

An association has been reported between dynamic anterior pelvic tilt (APT) and hamstring injuries; however, no research has examined if a training-based preventive intervention could alter APT. Therefore, the aim of the present study was to examine if a specific 6-week multimodal intervention, based on the theoretical influence of neighbouring joints and biomechanical interactions between muscles that are inserted to the pelvis, induced changes in APT, during walking gait, hamstring flexibility and trunk endurance. Thirty-five active healthy males volunteered for this single-blind controlled trial and were split into two groups based on baseline data: a control group (CG, n = 20, continued their normal physical activities), and an intervention group (IG, n = 15, performed the intervention programme for 18 sessions over 6 weeks). A significant (p = 0.001) decrease in the APT kinematics during gait, significant increase in the Active Knee Extension Test (p = 0.001), and a significant increase in trunk endurance performance for flexion (p = 0.001), extension (p = 0.001) and side bridge (p = 0.001) were observed, in IG after the 6-week programme, compared to CG. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effect of repeated-sprint training (RST) vs combined RST and resistance training with superimposed vibrations on repeated-sprint ability (RSA) and lower-body power output in male rugby players. Methods: Players were divided into 2 training groups. One group performed RST (n = 10) 2 d/wk and the other performed RST l d/wk and squat resistance training with superimposed vibrations on the second day (RS+ST; n = I0). The squat training was carried out with a volume similar (ie, number of sets and repetitions) to that of the RST. The training period lasted 6 wk, and it was carried out as a supplement to the regular rugby training sessions. Results: Substantial improvements in RSA mean time (RSAmean; +2.3%/ES: 0.77 vs +4.1%/ES: 0.91), RSA percent decrement (%Dec; -25.6%/ES: 1.70 vs -23.2%/ES: 0.99), and squat absolute power output (+5.0%/ES:0.36 vs +17.2%/ES: 0.93) were obtained in RST and RS+ST, respectively. Substantial improvements in RSA best lime (RSAbest; +2.6%/ES: 0.61) and squat power output normalized to body mass (+18.6%/ES: 0.76) only occurred in RS+ST. Both pretest and posttest RSAmean were largely correlated with the RSAbest. However, there were only unclear, small to moderate correlations between individual changes in squat power output and either RSAmean or RSAbest. Conclusion: Combined RST and resistance training induced improvements of greater magnitude in both repeated-sprint performance and muscle power output than the RST alone. The lack of substantial correlations between individual changes in repeated-sprint and muscle-power performance suggests that the same subjects were not systematically low or high responders to both RST and strength training. [ABSTRACT FROM AUTHOR]

The aims of the current study were to examine the magnitude of between-GPS-models differences in commonly reported running-based measures in football, examine between-units variability, and assess the effect of software updates on these measures. Fifty identical-brand GPS units (15 SPI-proX and 35 SPI-proX2, 15 Hz, GPSports, Canberra, Australia) were attached to a custom-made plastic sled towed by a player performing simulated match running activities. GPS data collected during training sessions over 4 wk from 4 professional football players (N = 53 files) were also analyzed before and after 2 manufacturer-supplied software updates. There were substantial differences between the different models (eg, standardized difference for the number of acceleration >4 m/s2 = 2.1; 90% confidence limits [1.4, 2.7], with 100% chance of a true difference). Between-units variations ranged from 1% (maximal speed) to 56% (number of deceleration >4 m/s2). Some GPS units measured 2-6 times more acceleration/deceleration occurrences than others. Software updates did not substantially affect the distance covered at different speeds or peak speed reached, but 1 of the updates led to large and small decreases in the occurrence of accelerations (-1.24; -1.32, -1.15) and decelerations (-0.45; -0.48, -0.41), respectively. Practitioners are advised to apply care when comparing data collected with different models or units or when updating their software. The metrics of accelerations and decelerations show the most variability in GPS monitoring and must be interpreted cautiously. [ABSTRACT FROM AUTHOR]

Purpose: This study describes the physical match demands relative to positional group in male rugby sevens. Methods: Ten highly trained players were investigated during competitive matches (N = 23) using GPS technology, heart rate (HR), and video recording. Results: The relative distance covered by the players throughout the match was 102.3 ± 9.8 m/min. As a percentage of total distance, 35.8% (36.6 ± 5.9 m/min) was covered walking, 26.0% (26.6 ± 5.5 m/min) jogging, 10.0% (10.2 ± 2.4 m/min) running at low intensity, 14.2% (14.5 ± 4.0 m/min) at medium intensity, 4.6% (4.7 ± 1.6 m/min) at high intensity, and 9.5% (9.7 ± 3.7 m/min) sprinting. For the backs, a substantial decrease in total distance and distance covered at low, medium, and high intensity was observed in the second half. Forwards exhibited a substantial decrease in the distance covered at medium intensity, high intensity, and sprinting in the 2nd half. Backs covered substantially more total distance at medium and sprinting speeds than forwards. In addition, the maximum length of sprint runs was substantially greater for the backs than forwards. On the contrary, forwards performed more tackles. The mean HR during the match in backs and forwards was similar, with the exception of time spent at HR intensities >90%HRmax, which was substantially higher in forwards. Conclusion: These findings provide a description of the different physical demands placed on rugby sevens backs and forwards. This information may be helpful in the development of positional and/or individualized physical-fitness training programs. [ABSTRACT FROM AUTHOR]