Propriétés psychométriques d'un questionnaire de mesure de l'activité physique chez l'enfant scolarisé âgé de six à dix ans : QAPE-semaine

Aims

To elaborate a physical activity questionnaire for school children aged between 6 and 10 years (QAPE-semaine) and to study the psychometric properties (face validity, acceptability, test-retest reproducibility, criterion validity).

Methods

The questionnaire measures physical activities at school, during leisure-time and other activities. Three scores are calculated: variety of physical activities, intensity and sedentary. The questionnaire was pre-tested to study the content validity, and was administered twice to 185 children from two elementary schools. The validity was studied by comparing the results of the questionnaire outcomes with a one day-recall (QAPE-hier) filled out in two occasions (to measure activities during a non school-day and a school-day). The statistic used was the intraclass correlation coefficient (ICC).

Results

The QAPE-semaine was acceptable. The ICC for the reproducibility of variety of physical activities, intensity and sedentary scores were 0.54, 0.47 and 0.68, respectively; and 0.54, 0.56 and 0.64 for the criterion validity of variety of physical activities, intensity and sedentary scores, respectively. All the ICC were significant (P < 0.0001).

Conclusion

The psychometric properties of the QAPE-semaine are satisfactory (moderate to good). Its administration in classes with school professor's help seems however essential.     

Administration de courte durée de prednisolone et sécrétion d'érythropoïétine

Introduction

The aim of the study is to assess the effects of a short-term therapeutical prednisolone intake on erythropoietin (EPO) secretion.

Synthesis

We studied, according to a double-blind, randomized cross-over protocol, the effects of a 7 day prednisolone intake (60 mg/day) in 10 healthy male subjects on hematocrit, EPO and hemoglobin concentrations. No significant change was found between the treatments (prednisolone/placebo) in the parameters investigated.

Conclusion

In view of the results obtained, short-term therapeutic glucocorticoid intake did not induce any enhancement of erythropoiesis via EPO stimulation that can result in ergogenic advantage during submaximal exercise.     

Validité et reproductibilité d’un dynamomètre inertiel basé sur l’accélérométrie

Introduction

The purpose of this study was to investigate the validity and reliability of an inertial dynamometer using accelerometry.

Methods

Fourteen subjects were tested during three successive sessions at four increasing loads (30, 50, 70 and 95% of the 1RM). Maximal force, velocity and power performances were simultaneously assessed by the Myotest (Myotest S.A., Switzerland), an inertial dynamometer using accelerometry, and by another control valid dynamometer witch combine accelerometer and linear position transducer. At three first loads, only minor differences appeared in between both dynamometers, correlations were excellent and coefficients of variation were good and similar. However, at 95% of the 1RM, Myotest validity and reliability became insufficient.

Conclusion

Bench press inertial assessment with accelerometer appeared valid and reliable at 30, 50 and 70% of the 1RM, but not at 95% of the 1RM.     

Étude prospective sur les accidents de décompression ostéomyoarticulaires en plongée de loisir : leurs facteurs de risque et leur potentiel évolutif en ostéonécrose dysbarique

Objectives

Dysbaric osteonecrosis is a complication that can result from repetitive and prolonged hyperbaric exposures and the correlation with a previous type 1 decompression sickness described as a joint pain remains a controversial subject. The study was designed to determine the risk factors of type 1 decompression sickness in recreational divers and their potential to shortly evolve into osteonecrosis.

Methods

All the osteoarthromuscular decompression sickness treated between October 2004 and November 2005 in one of three hyperbaric centers assigned in the Provence-Alpes-Côte d'Azur region were analyzed in a prospective way of standardized collections, and the majority was explored with MRI in order to screen ischaemic osteomedullar damages.

Results

Eleven cases (8,5%) were inventoried amongst the 129 diving accidents treated during this period. These joint pains were mainly located in the shoulder area (81%) and involved a majority of male experienced divers after performing deep and long dives (90%) furthermore more than 50% of these divers had greater than one dive within a twelve hour period. The average age was 38,5 years with a body mass index of 27,5 kg/m². All dives were performed with a dive computer without omitted decompression. Ten injured divers (90%) were examined by MRI shortly after the accident, but only one diver (10%) had lesions compatible with osteonecrosis.

Conclusion

This preliminary study shows that osteoarthromuscular decompression sickness in recreational diving are essentially involved in dives considered to carry a high risk for bubble production. The conditions of occurence appear also to be related with some individual factors that must be specified in other studies. Nevertheless, the risk of early underlying dysbaric osteonecrosis development is quite low.     

L’utilisation d’un nouveau système d’enregistrement de fréquence cardiaque battement à battement pour l’analyse traditionnelle de variabilité de fréquence cardiaque

Introduction

The measurement of Heart Rate Variability (HRV) is widely used in the field of sport's sciences. However, the analysis which rises from these measurements requires equipment that conform to those conditions outlined by the Task force of 1996.

Purpose

The purpose of the present study was: 1) to determine the accuracy of a new heart rate “beat to beat” recorder; Polar RS 800 (Polar Electro Oy, Kempele, Finlande); 2) and whether the quality of the tachogram is sufficient for traditional analysis of HRV.

Device and methods

Heart rate was recorded on 15 persons (eight men, seven women) in three different situations, simultaneous with this device and a gold standard (ADInstruments, Castle Hill, Australia, else Novacor, Rueil-Malmaison, France). Signals are synchronized and compared with Bland and Altman method to asses the accuracy. HRV analysis is made and the same comparison method was applied.

Conclusion

This device enables measurements of R-R intervals with a precision of ± 1 to 5 ms, and is sufficient to analyse HRV without bias.     

Effets d'une complémentation nutritionnelle en vitamines et minéraux sur la chute de force et les marqueurs biologiques consécutifs à un exercice excentrique chez des personnes âgées

Purpose

The effects of vitamins and minerals complex supplementation on maximal voluntary contraction decrease (FMV) and biological markers following an eccentric exercise at old people.

Method

Sixteen elderly subjects took either placebo (Pl group) or vitamins and minerals (Isoxan Senior, NHS, Rungis, France) (group S) for 21 d before an eccentric exercise and for 3 d after the exercise. The FMV and surface EMG activity (RMS) of the vastus lateralis (VL), vastus médialis (VM) and rectus fémoris (RF) were recorded before (Pre), immediately after (Post), 24 h (Post 24) and 48 h (Post 48) after the exercise. CCVThe creatine kinase (CK), lactate déshydrogénase, malondialdéhyde, and tumor necrosis Factor (TNFα) levels were analyzed.

Results

The reduced MVC (S: 11,2 ± 4,8%; Pl: 17,8 ± 10,4%, P < 0,01) after exercise was associated with a significant reduction in RMS VL, RMS VM and RMS RF values for both groups. A faster FMV recovery appeared at 48 h for the S group (P < 0.05). CK and TNFα values increased in post-exercise.

Conclusion

A dietary supplementation of a vitamin and mineral complex does not attenuate the loss of contractile function immediately after the running exercise, and it may accelerate the recovery of maximal force capacity after 48 h by limiting the post-exercise pro-inflammatory processes.     

Le passage de la posture classique à la posture en danseuse par le cycliste répond-il à une recherche de minimisation de l'effort musculaire ?

The subject of this study was to examine if the cyclist chose their propulsion position to minimise their muscular activity. The muscular efforts have been estimated by the calculation of the joints moments using the inverse dynamics. Eight adult subjects have participated in this study. Each subject has to pedal using classical position and dancer position at five different powers. The results show that at low power (around 100 W) the joints moments are sensibly the same between classic and dancer position. But when their output power increases, joints moments using dancer position were significantly inferior in dancer as opposed to classic position. The Discussion suggests that when cyclists pedal at high power, using dancer position make the cyclist able to minimize his muscular efforts.     

Intérêt d’un réentraînement à l’effort intermittent individualisé chez l’adolescent obèse

Introduction

To assess in six obese teenagers, the effects of 30 sessions (three days/week) of 50-minute individualised interval training on cardiorespiratory and metabolic parameters at rest and during exercise.

Synthesis

After this programme, fat mass decreases (10.8%) while BMI did not change. The expiratory reserve volume improved (44.6%). Maximal aerobic power, oxygen pulse and maximal ventilation are higher (12.4%; 16.9%; 17.2% respectively). First and second ventilatory threshold are increased (26.1% and 17.3%).

Conclusion

This study demonstrates the efficiency of this individualised training programme for obese teenagers. Such a programme may therefore provides additional benefits in weight management of obesity.     

Traumatismes de l'épaule chez les joueurs français de rugby de haut niveau

Aim of the study

Specify the frequency and the type of injuries of the shoulder arising during the practice of professional rugby in France. Outcomes were studied according to the treatments performed.

Materials and methods

It is a matter of a retrospective study on 154 players of high level. Any shoulder injury endured during the practice of rugby was registered. The age of the player, his experience, his position on the field, the type of injury, the game phase, the treatment and eventual residual disability were specified.

Results

Ninety-eight players (64%) reported at least one injury of the shoulder. Thirty (19%) reported at least two injuries on the same shoulder. The acromio-clavicular joint injuries were the most frequent (49%). The treatment was medical in most of the cases. A rest of 17 days in average was noted. All the players came back to their better level. Instability of the gleno-humeral joint was retrieved by 15% of the players. A secondary treatment by surgical stabilization was noted in more than half of the cases. The rest was in average of one week after the injury. It was in average of 4 months after surgery. A significant persistent discomfort was retrieved by 43% of the non operated cases and by 27% of the operated cases.Different other injuries were noted: 17 clavicular fractures, 6 sterno-clavicular sprains, 5 rotator cuff injuries and 4 muscular contusions.

Discussion

Injuries of the shoulder are frequent among high level rugby players and represent an important source of morbidity. Injuries of the acromio-clavicular joint are the most frequent. The medical treatment allows a quick return to sport without level loss in mostly cases. Gleno-humeral instability represents the second traumatism in terms of frequency. A secondary treatment by surgical stabilization is preferable.     

Évolution chez l'homme de l'Insulin-Like Growth Factor-I dans le liquide interstitiel musculaire suite à un exercice en résistance

Introduction

The impact of resistance exercise on the growth of the vastus lateralis was assessed through interstitial microdialysis measurement of free Insulin-like Growth Factor-I at +3 h30, +4 h50 and +6 h after exercise in 4 healthy subjects.

Results

We observed 3 h30 after exercise an interstitial increase in 3 over 4 subjects, and thereafter a progressive decrease. In the mean time, free or total plasma concentrations did not change.

Conclusion

Resistance exercise seemed to induce an early increase of muscle interstitial free Insulin-like Growth Factor-I in order to initiate muscle growth by an autocrine – paracrine way.     

Analyse de l'électrocardiogramme et de l'échocardiographie de 181 footballeurs professionnels tunisiens

Objectives

The aim of our work was to determine the frequency of various cardiovascular abnormalities and atypical aspects observed in Tunisian competitive athletes.

Material and methods

Our population was constituted of 181 professional football players (average age 23.1 ± 3.9 years) consulted in “Centre National de la Médecine et des Sciences de Sport” of Tunis with to obtain medical certificate authorizing professional football practice.

Results

Electrocardiogram was strictly normal in 67 players (37%). Twenty-nine players had conduction abnormalities. Repolarisation abnormalities were noted in 20 players. Echocardiography was normal in 129 players (71.3%). Ten cases of valvular heart disease were found. The mean left ventricular end-diastolic diameter was 53 ± 4 mm and the mean left ventricular mass was 202.6 ± 42.7 g. The mean relative wall thickness was 0.380. The left ventricular hypertrophy was present in 42 players.

Conclusion

Cardiovascular abnormalities found in electrocardiogram and echocardiography in the Tunisian professional football players are comparable with those usually observed in elite athletes.     

Relation entre la puissance et la raideur musculotendineuse chez les sportifs de haut niveau

Goal

The aim of this study was to test the relation between the reactive power and the stiffness of the legs in high trained athletes (sprinters and skiing racers).

Method

A simple method to measure, in field conditions, the leg stiffness during maximal bouncing was used on twenty-eight sprinters, and twenty-nine skiing racers. In addition, the mechanical power called reactive power was calculated according to the method proposed by Bosco. The relationship between stiffness and power was observed in the different groups.

Results

The value of stiffness obtained was 29,866 ± 7372 N.m⁻¹. The power was equal to 52.33 ± 8,72 W.kg⁻¹. The main result of this study was that a relation between stiffness and power was obtained only in the sprinters (r² = 0,68, P < 0,001). This result stressed the influence of the sport speciality on the stiffness control.

Conclusion

The power measured during maximal bouncing, called reactive power is correlated with the leg's stiffness when subjects are trained to produce power in similar conditions. No correlation was obtained in skiing racers. The stiffness measurement was then a complementary test in the physical evaluation of the athletes.     

Effet du port d'une combinaison intégrale et d'une trifonction sur la vitesse de nage et l'amplitude du cycle de bras en triathlon

Introduction

The purpose of this study was to compare the influence of complete wetsuit and tri-function on the swimming speed and arm stroke characteristics in crawl by triathletes.

Synthesis

Seven triathletes have executed three randomised trials of 400 m front crawl at maximal intensity: without wetsuit, complete wetsuit and tri-function.

Conclusion

Results pointed out that the complete suit allows a significant improvement of the performance and of the distance per cycle by report the swimming with a tri-function.