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Hammouda O.,Research Laboratory Sport Performance Optimisation | Chtourou H.,Research Laboratory Sport Performance Optimisation | Chtourou H.,University of Sfax | Chaouachi A.,Research Laboratory Sport Performance Optimisation | And 7 more authors.
Asian Journal of Sports Medicine | Year: 2013

damage responses after the level-1 Yo-Yo intermittent recovery test (YYIRT) in young football players. Methods: Fifteen male football players (17.42 ± 0.2 yrs, 69.91 ± 4.4 kg, 178.64 ± 3.8 cm; mean ± SD) participated in this study. Fasting blood samples for various biochemical parameters (i.e. lactate (Lac), glucose (GLC), triglycerides (Tri), creatine kinase (CK), uric acid (UA)) collected from a forearm vein after 5-min of seated rest and 3-min after the test. Moreover, rating of perceived exertion (RPE) and maximal heart rate during and after the YYIRT were recorded. Results: Mean levels of the selected biochemical markers were raised after the YYIRT exercise (P<0.001 for the other markers). Moreover, lipid parameters increased significantly after the test (P<0.01 for Tri and P<0.001 for HDL). Conclusion: These findings confirm the higher metabolic demand of aerobic as well as anaerobic metabolism and reflect a significant mobilization of purine cycle during the YYIRT. The increase of muscle damage markers also reflects the higher anaerobic solicitation. From these findings, we can conclude the importance of aerobic and anaerobic metabolism during soccer-specific endurance performance (i.e. YYIRT, soccer match). © 2013 by Sports Medicine Research Center, Tehran University of Medical Sciences, All rights reserved.


Ouergui I.,Research Unit Athletic Performance and Physical | Hammouda O.,Research Laboratory Sport Performance Optimisation | Chtourou H.C.,Research Laboratory Sport Performance Optimisation | Zarrouk N.,Neurophysiologie de la Vigilance de lAttention et des Performances | Rebai H.,Laboratory of Cardio Circulatory
Journal of Sports Medicine and Physical Fitness | Year: 2013

Aim. Objective of the study was to determine the effects of a kick-boxing match on muscle power of the upper and lower body as well as the associated perceived exertion in young men. Methods. Eighteen well trained kick-boxers volunteered to participate in a competitive sparring bout preceded and followed by three anaerobic tests as follow: squat jump (SJ) and counter movement jump (CMJ) for legs and 30-s Wingate test for arms. The sparring bout consisted of three 2 min rounds with 1 min recovery period in-between. Blood lactate (BL), heart rate (HR) and rating of perceived exertion (RPE) were analyzed before and after each round. Results. The results showed that vertical jump distance in SJ and CMJ were significantly lower after the kick-boxing match (27.92±3.84 vs. 25.28±4.39 cm; 29.8±5.33 vs 28.48±4.64 cm, for SJ and CMJ respectively). Likewise, peak and mean power in the Wingate test decreased significantly after the sparring bout (5.89±0.69 vs. 5.26±0.66 W·kg-1 and 4.51±0.53 vs. 4.12±0.51 W·kg-1 for PP and MP respectively; P<0.001). Moreover, we found a significant increase in BL, HR, and RPE after the kick-boxing match (P<0.001). BL increased significantly after the second and third round from the post round one values' (P<0.001). Conclusion. These findings showed that a single kick-boxing match is of sufficient intensity to stress the anaerobic metabolism. Thus, training protocols should include exercises that train the anaerobic energetic pathways for upper and lower body.


Jebali T.,Research Laboratory Sport Performance Optimisation | Jebali T.,University of Sfax | Moalla W.,University of Sfax | Elloumi M.,University of Sfax | And 6 more authors.
Biology of Sport | Year: 2013

The aim of this study was to investigate the heart rate (HR) responses, the rate of perceived exertion (RPE), and the feeling during physical education schooling while performing traditional games activities compared to intermittent exercise. Nineteen pre-pubertal children randomly performed on different days two types of lessons (intermittent running mode vs. traditional Tunisian "Raqassa" game) lasting 12-min each. HR was continuously recorded during both lessons, while ratings of perceived exertion and Feeling values were recorded after the sessions. The mean HR value during the traditional game was significantly higher than during intermittent exercise (p<0.05). Conversely, the perceived exertion score was significantly higher after intermittent exercise than the traditional exercise game (p<0.05), showing that the higher cardiovascular strain of the game was perceived as "lighter" than the run. Simultaneously, the children's Feeling was significantly higher after the traditional game than intermittent exercise (p<0.001), showing a higher satisfaction from playing with respect to running. Exercise based on the "Raqassa" traditional game could be used in pre-pubertal children as an alternative or as an additional method for suitable cardiovascular stimulation during physical education lessons with lower perceived exertion and better feeling compared to intermittent running.


Jarraya S.,Research Laboratory Sport Performance Optimisation | Jarraya S.,University of Sfax | Jarraya M.,Research Laboratory Sport Performance Optimisation | Jarraya M.,University of Sfax | And 4 more authors.
Biological Rhythm Research | Year: 2014

The aim of this study was to investigate the effects of the time of day and partial sleep deprivation on cognitive performances (i.e., attention and reaction time [RT]) of the handball goalkeeper (GK). The protocol involved 12 healthy GK volunteer males (age: 18.5 ± 1.7 years, level of experience: 8.3 ± 2.4 years, height: 1.80 ± 5.8 cm; body-mass: 79 ± 4.2 kg). They performed three cognitive tasks, i.e. the RT test, the Stroop test, and the barrage test, respectively, to evaluate the RT, the selective attention (SA), and the constant attention (CA) following the two situations of partial sleep deprivation, i.e. in the beginning (SDB) and the end (SDE) of the night, and a reference night which is a full night of habitual sleep. Resting oral temperature was measured at the beginning of each test session. Each of the three experimental conditions was separated by a 72-h period. The analysis of variance revealed a significant sleep deprivation × test-time effect on the RT, the SA, and the CA. These variables decreased significantly from morning to afternoon for all three experimental conditions. It seems that the RT is more affected by SDE than SDB (p < 0.05; -41% vs. 49% after SDE and SDB, respectively); however, SA and CA are more affected by SDB than SDE (p < 0.05; 63% vs. 47% for SA and 39% vs. 29% for CA after SDB and SDE, respectively). Furthermore, the partial sleep deprivation causes a phase advance of the core temperature. In addition, cognitive performances are not in phase with the rhythm of core temperature for all three experimental conditions. In conclusion, the partial sleep deprivation negatively affect cognitive performances in the handball goalkeeper. © 2013 Taylor & Francis.


PubMed | Research Laboratory Sport Performance Optimisation, INNOVA Health & Sport Institute and Pablo De Olavide University
Type: | Journal: Journal of human kinetics | Year: 2014

This study examined the relationship between lower body power and repeated as well as single sprint performance in soccer players. The performance of nineteen male soccer players was examined. The first testing session included the countermovement jump (CMJL) and the progressive full squat (FSL), both with external loads. Power in the CMJL and FSL was measured with each load that was lifted. The second session included a protocol of 40-m repeated sprints with a long recovery period (2 min). The number of sprints executed until there was a 3% decrease in performance for the best 40-m sprint time was recorded as a repeated sprint index (RSI). The RSI was moderately associated with power output relative to body mass in the CMJL and FSL (r = 0.53/0.54, p 0.05). The most and least powerful players (determined by FSL) showed significant differences in the RSI (9.1 4.2 vs. 6.5 1.6) and 10 m sprint time (p 0.01). Repeated and single sprints are associated with relatively lower body power in soccer players.


PubMed | Research Laboratory Sport Performance Optimisation, Research Unit Athletic performance and physical rehabilitation of the High Institute of Sport and Physical education Kef and University of Sao Paulo
Type: Journal Article | Journal: Asian journal of sports medicine | Year: 2015

To verify whether active recovery (AR) applied after a kickboxing match resulted in better performance in anaerobic tests when compared to passive recovery (PR).Eighteen kickboxers volunteered to participate on a Kickboxing match preceded and followed by anaerobic tests: squat jump (SJ), the counter movement jump (CMJ) and the upper-body Wingate test. Blood lactate (BL), heart rate (HR) and rate of perceived exertion (RPE) were analyzed before and after rounds. The recovery sessions consisted of 10min at 50% of maximal aerobic speed or PR. BL was measured at 3, 5 and 10 min after the match, while HR, RPE and anaerobic power were assessed after the recovery period.BL, HR and RPE increased significantly (P<0.001) during the match. BL was lower (P<0.001) after AR compared to PR at 5 min and 10 min (e.g. AR: 8.94 0.31 mmol.l(-1), PR: 10.98 0.33 mmol.l(-1)). However, PR resulted in higher (P<0.05) upper-body mean power (4.65 0.5 W.kg(-1)) compared to AR (4.09 0.5 W.kg(-1)), while SJ and CMJ were not affected by the recovery type.The lactate removal was improved with AR when compared with PR, but AR did not improve subsequent performance.


Hammouda O.,Research Laboratory Sport Performance Optimisation | Chtourou H.,Research Laboratory Sport Performance Optimisation | Chaouachi A.,Research Laboratory Sport Performance Optimisation | Chahed H.,Laboratory of Biochemistry | And 5 more authors.
Journal of Sports Sciences | Year: 2013

This study aimed to investigate footballers' diurnal variation of performance during the Yo-Yo intermittent recovery test and the associated biochemical responses. Fifteen male footballers (17.3 ± 0.3 years, 69.1 ± 4.2 kg, 179.7 ± 3.6 cm) performed two randomised Yo-Yo tests at 07:00 h and 17:00 h. Blood samples were collected before and 3 min after each test for the assessment of metabolic responses. Resting oral temperature and rating of perceived exertion (RPE) after and peak heart rate during the Yo-Yo test were recorded at both times-of-day. Core temperature and performances during the Yo-Yo test increased from the morning to the evening (P < 0.0005 and P = 0.01, respectively) without significant time-of-day effects on peak heart rate and RPE. Moreover, pre-and post-Yo-Yo test biochemical parameters (high-density lipoprotein, triglycerides, glucose, creatine-kinase) were higher at 17:00 h than 07:00 h (160.45 ± 18.68 vs. 173.73 ± 14.48 before and 191.18 ± 21.13 vs. 219.27 ± 27.74 IU · L-1 after the Yo-Yo test at 07:00 h and 17:00 h, P = 0.032 and P < 0.0005, respectively for creatine-kinase). Only post-exercise lactate levels were higher in the evening (9.82 ± 0.65 vs. 10.86 ± 0.33 mmol · L-1, P < 0.0005) with all biochemical variables being increased after the exercise (P < 0.0005). These findings suggest a possible link between the diurnal fluctuation of metabolic responses and the related pattern of specific-endurance performances in footballers. Therefore, the higher biochemical responses observed in the evening could explain, partially, the greater performance and metabolic solicitation at this time-of-day. © 2013 Copyright Taylor and Francis Group, LLC.


Hammouda O.,Research Laboratory Sport Performance Optimisation | Chtourou H.,Research Laboratory Sport Performance Optimisation | Chaouachi A.,Research Laboratory Sport Performance Optimisation | Chahed H.,Laboratory of Biochemistry | And 6 more authors.
Asian Journal of Sports Medicine | Year: 2012

Purpose: Prolonged physical exercise results in transient elevations of biochemical markers of muscular damage. This study examined the effect of short-term maximal exercise on these markers, homocysteine levels (Hcy), and total antioxidant status (TAS) in trained subjects. Methods: Eighteen male football players participated in this study. Blood samples were collected 5-min before and 3-min after a 30-s Wingate test. Results: The results indicated that plasma biochemical markers of muscle injury increased significantly after the Wingate test (P<0.05). Moreover, significant increase of white blood Cells and their main subpopulations (i.e. monocytes, neutrophiles, and lymphocytes) (P<0.001) has been observed. Likewise, uric acid, total bilirubin, and TAS increased significantly after exercise (P<0.05). However, Hcy levels were unaffected by the Wingate test (for 3-min post-exercise measurement). Conclusions: Short-term maximal exercise (e.g. 30-s Wingate test) is of sufficient intensity and duration to increase markers of muscle damage, and TAS; but not Hcy levels. Increases in the selected enzymes probably come primarily from muscle damage, rather than liver damage. Moreover, increase of TAS confirms the Wingate test induced oxidative stress. © 2012 by Sports Medicine Research Center.


Bouzid M.A.,University of Lille Nord de France | Hammouda O.,Research Laboratory Sport Performance Optimisation | Matran R.,Service EFR | Robin S.,Service EFR | Fabre C.,University of Lille Nord de France
PLoS ONE | Year: 2014

Purpose: The aim of this study was to evaluate whether oxidative stress markers and biomarkers of muscle injury would be affected by aging at rest and in response to an incremental exhaustive exercise. Methods: Fifteen young (20.3±2.8 years) and fifteen older adults (65.1±3.5 years) performed an incremental cycle ergometer test to exhaustion. Before and after exercise, oxidative stress [superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione reductase (GR), ascorbic acid, α-Tocopherol, malondialdehyde (MDA)] and muscle injury [creatine kinase (CK), lactate deshydrogenase (LDH)] biomarkers were assessed. Results: At rest, there was no difference in oxidative stress markers and LDH level between the groups, however CK was significantly higher in the young group than the elderly group (p<0.05). During recovery, in comparison with resting values, a significant increase in SOD (1092±145.9 vs. 1243±98 U/g Hb), GPX (67.4±12.7 vs. 79.2±15.6 U/g Hb) and GR (6.5±0.9 vs. 7.7±0.5 U/g Hb) activities were observed only in the young group (p<0.05). MDA has increased only in the older group (0.54±0.2 vs. 0.79±0.2 μmol/l) (p<0.01). CK increased in both groups (young group: 122.5±22.2 vs. 161.9±18.7 UI/l; older group: 88.8±34.1 vs. 111.1±25.9 UI/l) (p<0.01), however LDH has increased only in the young group (400.5±22.2 vs. 485618.7 UI/l) (p<0.01) without alteration in the older group (382.8±34.1 vs. 418.5±25.9 UI/l). Conclusions: These findings indicate that aging is associated with a decrease in antioxidant efficiency and an increase in oxidative stress damage. Furthermore, older adults would not more susceptible to exercise-induced muscle injury than young people. © 2014 Bouzid et al.


PubMed | Research Laboratory Sport Performance Optimisation
Type: Journal Article | Journal: Asian journal of sports medicine | Year: 2013

Prolonged physical exercise results in transient elevations of biochemical markers of muscular damage. This study examined the effect of short-term maximal exercise on these markers, homocysteine levels (Hcy), and total antioxidant status (TAS) in trained subjects.Eighteen male football players participated in this study. Blood samples were collected 5-min before and 3-min after a 30-s Wingate test.The results indicated that plasma biochemical markers of muscle injury increased significantly after the Wingate test (P<0.05). Moreover, significant increase of white blood Cells and their main subpopulations (i.e. monocytes, neutrophiles, and lymphocytes) (P<0.001) has been observed. Likewise, uric acid, total bilirubin, and TAS increased significantly after exercise (P<0.05). However, Hcy levels were unaffected by the Wingate test (for 3-min post-exercise measurement).Short-term maximal exercise (e.g. 30-s Wingate test) is of sufficient intensity and duration to increase markers of muscle damage, and TAS; but not Hcy levels. Increases in the selected enzymes probably come primarily from muscle damage, rather than liver damage. Moreover, increase of TAS confirms the Wingate test induced oxidative stress.

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