Monoem Haddad

Influence of fatigue, stress, muscle soreness and sleep on perceived exertion during submaximal effort.

The aim of this study was to assess the effects of the Hoopers Index variations (i.e., self-ratings of fatigue, stress, delayed onset muscle soreness (DOMS), and sleep) on rating of perceived exertion during a 10 min submaximal exercise training session (RPE-10 min) and then check the stability and the internal consistency of RPE-10 min. Seventeen junior soccer players took part in this study. The individual Hoopers indices taken before each training session were correlated with RPE-10 min during a constant intensity and duration effort (10 min) using Pearson product moment correlation. Intraclass correlation (ICC) was used to assess the internal consistency of the RPE-10 min. All individual correlations between RPE-10 min and quality of sleep and quantity of fatigue, stress, and DOMS were non-significant (p>0.05). No significant correlations were resulted between RPE-10 min and Hoopers Index in all athletes. The ICC of RPE-10 min was 0.77 thus demonstrating internal consistency. The results of the present study demonstrated the objectivity and utility of RPE as a psychological tool for monitoring training during traditional soccer training. Therefore, the results of the present study suggest that fatigue, stress, DOMS and sleep are not major contributors of perceived exertion during traditional soccer training without excessive training loads. It seems that psychobiological factors other than fatigue, stress, DOMS and sleep may have mediated the 10 min exercise perceptual intensity.

Static Stretching Can Impair Explosive Performance for At Least 24 Hours

Abstract Haddad, M, Dridi, A, Chtara, M, Chaouachi, A, Wong, DP, Behm, D, and Chamari, K. Static stretching can impair explosive performance for at least 24 hours. J Strength Cond Res 28(1): 140–146, 2014—The aim of this study was to compare the effects of static vs. dynamic stretching (DS) on explosive performances and repeated sprint ability (RSA) after a 24-hour delay. Sixteen young male soccer players performed 15 minutes of static stretching (SS), DS, or a no-stretch control condition (CC) 24 hours before performing explosive performances and RSA tests. This was a within-subject repeated measures study with SS, DS, and CC being counterbalanced. Stretching protocols included 2 sets of 7 minutes 30 seconds (2 repetitions of 30 seconds with a 15-second passive recovery) for 5 muscle groups (quadriceps, hamstring, calves, adductors, and hip flexors). Twenty-four hours later (without any kind of stretching in warm-up), the players were tested for the 30-m sprint test (with 10- and 20-m lap times), 5 jump test (5JT), and RSA test. Significant differences were observed between CC, SS, and DS with 5JT (F = 9.99, p < 0.00, effect size [ES] = 0.40), 10-m sprint time (F = 46.52, p < 0.00, ES = 0.76), 20-m sprint time (F = 18.44, p < 0.000, ES = 0.55), and 30-m sprint time (F = 34.25, p < 0.000, ES = 0.70). The significantly better performance (p < 0.05) was observed after DS as compared with that after CC and SS in 5JT, and sprint times for 10, 20, and 30 m. In contrast, significantly worse performance (p < 0.05) was observed after SS as compared with that after CC in 5JT, and sprint times for 10, 20, and 30 m. With RSA, no significant difference was observed between different stretching protocols in the total time (F = 1.55, p > 0.05), average time (F = 1.53, p > 0.05), and fastest time (F = 2.30, p > 0.05), except for the decline index (F = 3.54, p < 0.04, ES = 0.19). Therefore, the SS of the lower limbs and hip muscles had a negative effect on explosive performances up to 24 hours poststretching with no major effects on the RSA. Conversely, the DS of the same muscle groups are highly recommended 24 hours before performing sprint and long-jump performances. In conclusion, the positive effects of DS on explosive performances seem to persist for 24 hours.

Injury rates in professional soccer players during Ramadan

Abstract Many of the socio-cultural lifestyle and dietary changes that take place during Ramadan may affect the risk of injury in athletes, but little evidence is available. The aim of the present study was to examine the effects over two consecutive years of the holy month of Ramadan on injury rates in 42 professional players of a Tunisian top-level professional soccer team. Players were retrospectively organized into fasting and non-fasting groups and monitored for 3 months: 4 weeks before Ramadan, during the month of Ramadan (4 weeks), and 4 weeks after Ramadan each year. During Ramadan, training started at 22.00 h. The circumstances (training/match) and mechanism of injury (traumatic/overuse) were recorded. No significant differences between the three periods were observed for weekly mean training load, training strain, training duration, and Hoopers Index (quality of sleep, and quantities of stress, delayed-onset muscle soreness, and fatigue). Compared with non-fasting players, fasters had a lower (P < 0.05) Hoopers Index and stress during and after Ramadan. No significant difference in injury rates was observed between fasting and non-fasting players. Nevertheless, the rates of non-contact (6.8 vs. 0.6 and 1.1) and training overuse (5.6 vs. 0.6 and 0.5) injuries were significantly higher in fasting players during the month of Ramadan than before or after Ramadan. In conclusion, Ramadan, along with the corresponding changes in nutritional habits, sleeping schedule, and socio-cultural and religious events, significantly increased overuse and non-contact injuries in fasting players despite the fact that the training load, strain, and duration were maintained.

Physiological and Perceived Exertion Responses during International Karate Kumite Competition.

Purpose Investigate the physiological responses and rating of perceived exertion (RPE) in elite karate athletes and examine the relationship between a subjective method (Session-RPE) and two objective heart-rate (HR)-based methods to quantify training-load (TL) during international karate competition. Methods Eleven karatekas took part in this study, but only data from seven athletes who completed three matches in an international tournament were used (four men and three women). The duration of combat was 3 min for men and 2 min for women, with 33.6±7.6 min for the first interval period (match 1–2) and 14.5±3.1 min for the second interval period (match 2–3). HR was continuously recorded during each combat. Blood lactate [La-] and (RPE) were measured just before the first match and immediately after each match. Results Means total fights time, HR, %HRmax, [La-], and session-RPE were 4.7±1.6 min, 182±9 bpm, 91±3%, 9.02±2.12 mmol.L-1 and 4.2±1.2, respectively. No significant differences in %HRmax, [La-], and RPE were noticed across combats. Significant correlations were observed between RPE and both resting HR (r=0.60; P=0.004) and mean HR (r=0.64; P=0.02), session-RPE and Banister training-impulse (TRIMP) (r=0.84; P<0.001) and Edwards TL (r=0.77; P<0.01). Conclusion International karate competition elicited near-maximal cardiovascular responses and high [La-]. Training should therefore include exercise bouts that sufficiently stimulate the zone between 90 and 100% HRmax. Karate coaches could use the RPE-method to follow competitors competition loads and consider it in their technical and tactical training.

Influence of exercise intensity and duration on perceived exertion in adolescent Taekwondo athletes

Abstract The aim of this study was to examine the influence of exercise intensity and session duration on rating of perceived exertion (RPE) in adolescent Taekwondo (TKD) athletes. Twelve male youth competitive TKD athletes, aged between 13 and 18 years took part in this study. Training data (368 individual sessions) were collected during the 12 weeks of the pre-competitive TKD season. Daily training load was calculated using the heart rate and the session-RPE. Exercise intensity was also classified in five zones [i.e. 50–60%, 61–70%, 71–80%, 81–90% and 91–100% of maximal heart rate (HRmax)] and the time spent in each zone was expressed as percentage of total session time. The analysis of variance showed a significant main effect for zone (p<0.001) with most of the time (69%) spent at intensities between 61 and 90% of HRmax, and only 10% spent above 91% (mean differences compared to the other zones ranging from –6.6% versus zone 1 to –14.8% versus zone 3; p<0.0001). The individual correlation between session-RPE and HR-based methods were moderate to large. The stepwise multiple regression showed that RPE was influenced mainly by the time spent in the high intensity zone that explained 22.1% of the variance in RPE. Session duration accounted for only an additional 3.2%. The results suggest the time spent at high-intensity (i.e. between 91 and 100% HRmax) and only marginally the session duration influences the RPE referred to the whole training session. This seems to confirm that the determination of the TL multiplying the RPE and session duration is acceptable.

Greater effects of high- compared with moderate-intensity interval training on cardio-metabolic variables, blood leptin concentration and ratings of perceived exertion in obese adolescent females

This study examined the effects of high- vs. moderate-intensity interval training on cardiovascular fitness, leptin levels and ratings of perceived exertion (RPE) in obese female adolescents. Forty-seven participants were randomly assigned to one of three groups receiving either a 1:1 ratio of 15 s of effort comprising moderate-intensity interval training (MIIT at 80% maximal aerobic speed: MAS) or high-intensity interval training (HIIT at 100% MAS), with matched 15 s recovery at 50% MAS, thrice weekly, or a no-training control group. The HIIT and MIIT groups showed improved (p < 0.05) body mass (BM), BMI Z-score, and percentage of body fat (%BF). Only the HIIT group showed decreased waist circumference (WC) (p = 0.017). The effect of exercise on maximal oxygen uptake (VO2max) was significant (p = 0.019, ES = 0.48 and p = 0.010, ES = 0.57, HIIT and MIIT, respectively). The decrease of rate-pressure product (RPP) (p < 0.05, ES = 0.53 and ES = 0.46, HIIT and MIIT, respectively) followed the positive changes in resting heart rate and blood pressures. Blood glucose, insulin level and the homeostasis model assessment index for insulin decreased (p < 0.05) in both training groups. Significant decreases occurred in blood leptin (p = 0.021, ES = 0.67 and p = 0.011, ES = 0.73) and in RPE (p = 0.001, ES = 0.76 and p = 0.017, ES = 0.57) in HIIT and MIIT, respectively. In the post-intervention period, blood leptin was strongly associated with %BF (p < 0.001) and VO2max (p < 0.01) in the HIIT and MIIT groups, respectively, while RPE was strongly associated with BM (p < 0.01) in the HIIT group. The results suggest that high-intensity interval training may produce more positive effects on health determinants in comparison with the same training mode at a moderate intensity.

Time-motion analysis of elite male kickboxing competition

Abstract Ouergui, I, Hssin, N, Haddad, M, Franchini, E, Behm, DG, Wong, DP, Gmada, N, and Bouhlel, E. Time-motion analysis of elite male kickboxing competition. J Strength Cond Res 28(12): 3537–3543, 2014—The objective of the study was to analyze the time structure of high-level kickboxing matches. A total of 45 combats from 2 male World Championships were monitored using a time-motion analysis system. The combat time structure (i.e., high-intensity activity [HIA], low-intensity activity [LIA], and referee breaks or pauses) during competition and weight divisions was determined and compared. Results indicated that the time structures were HIA: 2.2 ± 1.2 seconds; LIA: 2.3 ± 0.8 seconds; pauses: 5.4 ± 4.3 seconds; and 3.4 ± 1.2 seconds between 2 subsequent HIA. The fighting to nonfighting ratio was found to be 1:1. Moreover, the number of HIA and LIA and the time of LIA decreased in latter rounds (e.g., the average number of HIA was 27.1 ± 7.1, 25.1 ± 6.6, and 24.9 ± 6.1, respectively, for rounds 1, 2, and 3), meanwhile the time and number of pauses increased (e.g., the average pause times were 12.8 ± 11.4, 22.3 ± 22.6, and 24.6 ± 23.3 seconds, respectively, for rounds 1, 2, and 3). The activity times did not differ among weight categories. The present results confirm the intermittent nature of kickboxing competition and provide coaches with more information on how to structure training sessions to mimic the physical demands in competition.

The Usefulness of Session Rating of Perceived Exertion for Monitoring Training Load Despite Several Influences on Perceived Exertion

Despite various contributing factors, session rating of perceived exertion has the potential to affect a large proportion of the global sporting and clinical communities since it is an inexpensive and simple tool that is highly practical and accurately measures an athletes outcome of training or competition. Its simplicity can help optimize performance and reduce negative outcomes of hard training in elite athletes.

Cardiac Parasympathetic Reactivation in Elite Soccer Players During Different Types of Traditional High-Intensity Training Exercise Modes and Specific Tests: Interests and Limits

Background: The cardiac parasympathetic reactivation is currently used in soccer with a daily or weekly monitoring. However, previous studies have not investigated how this cardiac parasympathetic reactivation is in elite soccer players along different types of traditional high-intensity training exercise and specific tests. In this context, the present study aim to analyse it and to determine the interests and limits of this type of physiological information. Objectives: The present study aims to examine how different traditional training exercise modes affect the cardiac parasympathetic reactivation function in elite soccer players. Materials and Methods: Twenty-two international soccer players participating in UEFA Champion’s League took part in this study (age: 24.3 ± 4.2 years; height: 178.1 ± 6.2 cm; body mass: 80.3 ± 5.7 kg). Players performed different training methods including: short-duration intermittent exercises (INT) in-line and with changes of direction (COD) (10 - 10 seconds, 15 - 15 seconds, 30 - 30 seconds, e.g. an alternance of 10 - 10 seconds is 10 seconds of running according to the maximal aerobic speed (MAS) and 10-sec of recovery), INT including agility and technical skills (8 - 24-seconds), small-sided-games (SSGs) with and without goalkeepers (2 vs. 2, 3 vs. 3, 4 vs. 4), and repeated sprint ability (RSA) efforts (10 × 20 m, 10 × 30 m, 15 × 20 m). Heart rate (HR) decline was recorded 3 minutes after each exercise. Results: HR declines were greater after the RSA compared to SSGs (P < 0.001) and INT (P < 0.01), especially at 1 min post-exercise. In addition, when the analysis focused on each type of exercise, greater HR declines were observed in on-field players at 1 minute when there was: inclusion of goalkeepers in SSGs (for 2 vs. 2 and 3 vs. 3, P < 0.01); increase of sprint distances or number of sprint repetitions in RSA (P < 0.01); increase of intensity (% of maximal aerobic speed), and the use of COD or inclusion of technical skills during INT, especially for the 30 - 30-seconds. Conclusions: This study revealed that cardiac parasympathetic reactivation function varied after INT, RSA and SSG, but also according to the rules manipulation. Therefore, this study provides interesting information for the training monitoring and players’ recovery profile, with the aim of facilitating a more efficient planning and manipulation of training recovery strategies according to their fitness markers.

Session-RPE Method for Training Load Monitoring: Validity, Ecological Usefulness, and Influencing Factors

Purpose: The aim of this review is to (1) retrieve all data validating the Session-rating of perceived exertion (RPE)-method using various criteria, (2) highlight the rationale of this method and its ecological usefulness, and (3) describe factors that can alter RPE and users of this method should take into consideration. Method: Search engines such as SPORTDiscus, PubMed, and Google Scholar databases in the English language between 2001 and 2016 were consulted for the validity and usefulness of the session-RPE method. Studies were considered for further analysis when they used the session-RPE method proposed by Foster et al. in 2001. Participants were athletes of any gender, age, or level of competition. Studies using languages other than English were excluded in the analysis of the validity and reliability of the session-RPE method. Other studies were examined to explain the rationale of the session-RPE method and the origin of RPE. Results: A total of 950 studies cited the Foster et al. study that proposed the session RPE-method. 36 studies have examined the validity and reliability of this proposed method using the modified CR-10. Conclusion: These studies confirmed the validity and good reliability and internal consistency of session-RPE method in several sports and physical activities with men and women of different age categories (children, adolescents, and adults) among various expertise levels. This method could be used as “standing alone” method for training load (TL) monitoring purposes though some recommend to combine it with other physiological parameters as heart rate.