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The objective of the present study was to investigate the effects of static and dynamic stretching alone and in combination on subsequent agility, sprinting, and jump performance. Eight different stretching protocols: (a) static stretch (SS) to point of discomfort (POD); (b) SS less than POD (SS KEY WORDS flexibility, stretch sequence, stretch intensity

The aim of the present study was to evaluate the influence of the Ramadan intermittent fast (RIF) on aerobic and anaerobic exercise performance in elite judo athletes (Judokas) maintaining their usual training loads. Physical performance tests (squat jump [SJ]), counter-movement jump [CMJ], 30-second repeated jump, 30-m sprint, and the multistage fitness test) and fatigue scores were measured in 15 elite Judokas on 4 occasions: before Ramadan (T1), at the beginning of Ramadan (T2), at the end of Ramadan (T3) and 3 weeks after Ramadan. Results showed that 30-m sprint performance, multistage shuttle run test, SJ, and CMJ did not change during Ramadan. However, average power during the 30-second repeated jump test was slightly lower at the end of Ramadan (22.4 [+ or -] 2.3 W/kg; P < 0.05) than before Ramadan (23.4 [+ or -] 2.3 W/kg). There was a minor reduction of 1.3 kg in body mass and an increase in total fatigue scores (T2, 19 [+ or -] 5; T3, 16 [+ or -] 4; both P < 0.05) during Ramadan in comparison with the control period (T1, 12 [+ or -] 3). These results show that the RIF has little effect on aerobic performance and on very short duration sprinting and jumping test performance in elite Judokas. Additionally, experienced athletes can maintain both sufficient energy intake and normal training loads during the RIF. The slight reduction in the 30-second jump test may be associated with reduced central drive and body mass. Collectively, these results suggest that the RIF has little effect on the performance of experienced Judokas, but Muslim athletes who train during the RIF should carefully periodize their training load and monitor their food intake and fatigue levels to avoid performance decrements. KEY WORDS Islamic fasting, sports, exercise, nutrition

The purpose of this study was to examine the influence of the sequence order of high-intensity endurance training and circuit training on changes in muscular strength and anaerobic power. Forty-eight physical education students (ages, 21.4 [+ or -] 1.3 years) were assigned to 1 of 5 groups: no training controls (C, n = 9), endurance training (E, n = 10), circuit training (S, n = 9), endurance before circuit training in the same session, (E+S, n = 10), and circuit before endurance training in the same session (S+E, n = 10). Subjects performed 2 sessions per week for 12 weeks. Resistance-type circuit training targeted strength endurance (weeks 1-6) and explosive strength and power (weeks 7-12). Endurance training sessions included 5 repetitions run at the velocity associated with [Vo.sub.2]max ([Vo.sub.2]max) for a duration equal to 50% of the time to exhaustion at [Vo.sub.2]max; recovery was for an equal period at 60% [Vo.sub.2]max. Maximal strength in the half squat, strength endurance in the 1-leg half squat and hip extension, and explosive strength and power in a 5-jump test and countermovement jump were measured pre-and post-testing. No significant differences were shown following training between the S+E and E+S groups for all exercise tests. However, both S+E and E+S groups improved less than the S group in 1 repetition maximum (p < 0.01), right and left 1-leg half squat (p < 0.02), 5-jump test (p < 0.01), peak jumping force (p < 0.05), peak jumping power (p < 0.02), and peak jumping height (p < 0.05). The intrasession sequence did not influence the adaptive response of muscular strength and explosive strength and power. Circuit training alone induced strength and power improvements that were significantly greater than when resistance and endurance training were combined, irrespective of the intrasession sequencing. KEY WORDS plyometric training, combined training, interval training, interference effect

Abstract Background This study is a cross sectional analysis, aiming to evaluate if atopy is as a risk factor for exercise induced bronchoconstriction (EIB) among Tunisian athletes. Methods Atopy was defined by a skin prick test result and EIB was defined as a decrease of at least 15% in forced expiratory volume in one second (FEV1) after 8-min running at 80–85% HRmaxTheo. The study population was composed of 326 athletes (age: 20.8 ± 2.7 yrs – mean ± SD; 138 women and 188 men) of whom 107 were elite athletes. Results Atopy was found in 26.9% (88/326) of the athletes. Post exercise spirometry revealed the presence of EIB in 9.8% of the athletes including 13% of the elite athletes. Frequency of atopy in athletes with EIB was significantly higher than in athletes without EIB [62.5% vs 23.1%, respectively]. Conclusion This study showed that atopic Tunisian athletes presented a higher risk of developing exercise induced bronchoconstriction than non-atopic athletes.

Young soccer players often use one particular dominant leg (DL) to perform dynamic movements which require strength, resulting in leg asymmetry. The aim of this study was to compare, in young soccer players, the effect of using DL and non-dominant leg (NDL) on time performance of two change of direction (COD) manoeuvres in several angles of COD. Seventy-three young male soccer players (mean ± SD, age: 16.1 ± 1.8 year) participated in this study. Players performed 10-m sprints, either in a straight line or with a COD (5 m straight ahead and a turn of 45°, 90°, 135° and 180° to the opposite side of the DL or NDL). Testing for COD speed was conducted over two different manoeuvres: (1) sidestepping and (2) bypass. Maximal isometric voluntary contraction of the knee extensors/flexors and hip abductors/adductors was also measured using a handheld dynamometer. For sidestepping, COD performance with use of the DL was significantly better compared to the NDL (P < 0.05) in all angles of COD. However, bypass COD performance through use of the DL was better compared to the NDL only when turning at 135°. Additionally, strength of the knee extensors/flexors and hip abductors of the DL was significantly (P < 0.05) greater than the NDL. The use of the DL allows better COD performance than the NDL when sidestepping manoeuvre is used. However, the DL allows better COD performance than the NDL only at 135° with the use of the bypass manoeuvre. Furthermore, the greater strength of the DL compared to the NDL may contribute to COD performance difference between legs. [ABSTRACT FROM AUTHOR]

There is abundant research involving the acute effects of stretching on subsequent performance; however, there is little information on dynamic stretch training programmes on range of motion (ROM), power and speed measures. It was the objective of this research to examine the training consequences of active dynamic stretching (ADS) and static dynamic stretching (SDS). A repeated measures design compared the effects of 8 weeks of warm-ups incorporating two dynamic stretch modalities: ADS and SDS on squat jump (SJ), countermovement jump (CMJ), 20-m sprint performances and repeated sprint ability (RSA) and hip ROM in 37 male soccer players. SJ height (SDS: 4.6%; ADS: 5.3%; p <0.05), CMJ height (SDS: 5.3%; ADS: 3.4%; p<0.05), CMJ force (SDS: 7.2%; ADS: 12.7%; p<0.001) and CMJ peak power (SDS: 3.9%; ADS: 3.3%; p<0.05) increased significantly after SDS and ADS training compared to the control group (no significant change). Sprint performance and RSA were not affected by either of the dynamic stretch training regimens. The SDS and ADS training programmes elicited similar improvements in flexibility (SDS: 57.6%; ADS: 45.1%; p<0.01) compared to the non-significant changes in the control group. The inclusion of ADS and SDS within the regular warm-up of an 8-week training programme can improve not only flexibility but also jump power measures as well. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to analyze the effect of different post-activation potentiation (PAP) protocols on initial-acceleration (0-10 m) and late-acceleration phases (10 to 30 m) within a repeated sprint ability (RSA) test. Methods: Twenty athletes (age: 20.8±1.2 years, height: 180.2±5.3 cm, body mass: 76.8±6.4 kg, % body fat: 10.9±2.8, and 3 repetition maximum [3- RM] of half-squats 152.9±14.8 kg) completed 4 testing sessions of RSA testing (7x30-m sprints, starting every 25s, with an active recovery in-between). Five minutes before the RSA-testing, conditioning protocols were performed: I) one half-squats at 90% of 1 repetition maximum (1RM) [PAP1]; II) two half-squats at 90% of 1 RM [PAP2]; III) three half-squats at 90% of 1 RM [PAP3], and (IV) the control protocol [CON]: no effort. Each conditioning condition was applied in a counterbalanced, randomized order on separate days separated by a minimum of 72 hours' rest. Results: ANOVA showed that PAP1 and PAP2 sessions were similar, and brought significantly improved results for: 0-30m and 0-10m sprints of the RSA-time (p<0.001, ES=large) vs the PAP3 and CON-conditions. For the late-acceleration phase of the RSA, the conditioning activity gave no effect (p>0.05, ES=small). Furthermore, magnitude-based inference revealed that both PAP1 and PAP2 protocols elicited changes >75% likelihood of exceeding the smallest worthwhile change (>99% likely) for mean sprint-time (RSAmean) and the percentage of sprint-decrement (RSAdec) in overall 0-30 m and 0-10 m of the RSA test. Conclusion: PAP1 and PAP2 exert a positive effect on the initial-acceleration phase of the RSA and could be considered in the preparation routine of repeated sprinting activities. [ABSTRACT FROM AUTHOR]

Background: ID polymorphism of the gene coding for the angiotensin I-converting enzyme (ACE) represents a determining factor in physical and athletic performance in the context of genetic conditioning of sports predisposition. The aim of this study was to show the potential importance of genetic factors in relation to the athletic status in Tunisian athletes., Methods: The ACE genotypes were established using polymerase chain reaction (PCR) amplification for 282 Tunisian athletes (endurance: N.=149 - power: N.=133), and 211 sedentary volunteers., Results: No significant difference was found in the ACE genotype distribution between athletes (36% DD, 49% ID, 15% II) and controls (CTR) (39% DD, 46% ID, 15% II; P=0.72). In contrast, a high significant difference between endurance and power groups were noted in genotype and alleles (χ2=10.32, P=0.0057; χ2=4,752, P=0.029, respectively). The elite endurance-athletes (N.=72) possess some inherent genetic advantage predisposing them to superior athletic performances compared to CTR for ACE alleles (χ2=3.51, P=0.06). In addition endurance trained athletes were also significantly different from CTR for ACE genotype (χ2=6.05, P=0.04). Furthermore, a significant difference have been found between elite power-athletes (N.=59) and CTR for ACE alleles (χ2=3.79, P=0.05)., Conclusions: Tunisian athletes exhibit insertion (I) and deletion (D) alleles of the ACE polymorphism associated with a high level of human endurance and power performance, respectively. This genetic background plays an important role in sporting potential and causes some individuals to be better adapted to specific physical training. This should be considered in athlete development to identify which sporting specialties should be trained for Tunisian talent promotion.