Effet d'un entraînement en endurance sur les concentrations de l'IGF-1 plasmatique chez le rat

Introduction

The aim of this study was to determine the effects of endurance training on IGF-1, corticosterone and insulin levels in male sedentary and trained rats.

Facts

IGF-1 concentrations decrease after training (p < 0.05), those of corticosterone increase (p < 0.01) whereas insulin levels remain stable.

Conclusion

A short period of endurance training leads to catabolic state with a decrease in IGF-1 concentrations and increase in corticosterone levels.     

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.     

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.     

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.     

Analyse de variables permettant la détermination du niveau d'un cycliste

Aims

We aimed to define a mathematical model allowing to foresee the level of a cyclist.

Methods

One hundred (and) six cyclists were classified according to their level and some of their physiological characteristics were measured with the threshold (4 mmol of lactate) and with the maximum values of their oxygen flow.

Results

To the threshold, power, lactatemy, age and size allow to foresee the level with an error rate of 27% ; to the maximum values, the criteria are development, flow in oxygen, lactatemy and age (error rate of 31%).

Conclusion

These results indicate that our mathematical model allows to envisage the level.     

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.     

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.     

Sedentary behavior during school-time: Sociodemographic,weight status,physical education class,and school performance correlates in Brazilian schoolchildren

Objectives

To investigate whether sedentary behavior during school-time is associated with gender, age, mother's education, having physical education classes, weight status, and academic performance.

Contribution à l’étude des effets d’un programme de réentraînement à l’effort sur les aptitudes physiques de patients atteints de bronchopneumopathie chronique obstructive

Aims

The purpose of this study was to evaluate the effect of a three-months’ training rehabilitation on the physical capacity of patients suffering from chronic obstructive pulmonary disease (COPD).

Methods

The aerobic and anaereobic capacity was evaluated in 36 patients (Stage 2) before and after a training rehabilitation period: (duration: three months, frequency: two sessions per week, intensity: 65% of aerobic threshold for 25 min, type: regular exercise on a bicycle).

Results

Training rehabilitation caused a statistically significant specific improvement of submaximal aerobic capacity and an increase of quadriceps and flexor of the fingers’ strength.     

Activité physique et obésité infantile : dépistage,prévention et prise en charge

Aim

This review is aimed to synthesize current scientific knowledge on the part played by physical activity in prevention and treatment of the paediatric obesity.

Current

The physical activity (and inactivity?) is unanimously recognized like an essential element of the fight against the obesity increase in children and adolescents. In the treatment the last meta-analysis and literature reviews confirm that the best strategy is the reduction of the sedentary behaviours, the increase in the physical activity associated with an education and restriction nutritional. On the other hand, the part played by the physical activity in the prevention interventions although not discussed, must be specified in its association with other elements such as nutritional education according to the age, of the obesity level… The physical activity practice as of the youth is to be associated an early tracking factor of risk. The recommendations of physical activity must be adapted to the required objective and the possibilities physical, physiological, sociological… of the subjects.

Conclusion

Although characteristics of the physical activity to prescribe for each specific objective; prevention, loss of or not taken again body mass weight, remain to be specified for the child and the teenager, an active way of life is one of the major factors of the fight against the increase in the prevalence of obesity.     

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.     

Observance du suivi médical obligatoire par les sportifs de haut niveau lorrains

Objectives

To measure high level athletes' level of compliance of their medical follow-up (in reference to the French law) and exploring their perception of it.

Method

Data were collected by self-questionnaire among the 614 high level athletes in the Lorraine region (East of France).

Main results

Response rate was 66.8%. In 2006, approximately a third of the athletes did not benefit from the two medical examinations carried out by a sport doctor. The great majority did benefit neither from dietetic assessment, nor of nutritional council. More than half of them stated that they had no psychological assessment. An athlete on five said that he did not have an electrocardiogram. All of these exams or assessments are however obligatory according to the French law. In 5% of the cases, the follow-up detected a health problem, generally a cardiac anomaly. The majority of the athletes felt that the follow-up was not a waste of time, not very constraining and that it was complete. Their positions were doubtful on its capacities to prevent wounds or to improve sporting performances.

Conclusion

A nation-wide study should be undertaken to check these worrying results in France.     

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.     

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.     

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.     

The utilisation of radiology for the teaching of anatomy in Canadian medical schools

Objective

To determine the utilisation of diagnostic imaging (radiology) as a department and/or imaging medium in the teaching of anatomy at the Canadian undergraduate medical education level.

Methods

The study objectives were achieved through the use of a questionnaire and a literature review. The anatomy department head at each English-based Canadian Medical School was contacted, and the individual most responsible for anatomy teaching in the medical school curriculum was identified. This individual was subsequently asked to complete a questionnaire that evaluated the involvement of radiology for anatomy teaching in their curriculum.

Results

The use and integration of radiology is a common practice in the teaching of anatomy in Canadian undergraduate medicine. Although the methods and extent of its use varied among institutions, every English-based Canadian medical school, except one, was using diagnostic imaging material in their instruction of anatomy. Furthermore, half of the institutions had a radiologist as a faculty member of their anatomy department to help teach and to use imaging to its full potential.

Discussion

This audit of anatomy departments suggests that diagnostic imaging has an important role to play in anatomy teaching in Canadian English-speaking medical schools.     

Reliability and validity of the Youth Leisure-time Sedentary Behavior Questionnaire (YLSBQ)

Objectives

To develop a questionnaire able to assess time spent by youth in a wide range of leisure-time sedentary behaviors (SB) and evaluate its test-retest reliability and criterion validity.

Évolution des paramètres physique et anthropométrique de jeunes rugbymen de haut niveau sur une saison sportive

Introduction

The objective of the study is to measure the evolution of the anthropometric and physical parameters in young elite rugby players during one rugby league season.

Results

This study shows an enhancement of the aerobic and lactic anaerobic performances in the first six months of the preparation. Therefore, these aptitudes decrease in April. There is no modification of the lactic anaerobic performance during the season.

Conclusion

This study shows the difficulty to organise the training planification during the winter period for the elite players. The reason for the rugby league season fatigue has yet to be defined and will be the purpose of a future study.     

Validity and reliability of the Norwegian translation of the Achilles tendon Total Rupture Score

Purpose

Patient reported outcome measures (PROMs) are increasingly being used in clinical research. The Achilles tendon Total Rupture Score (ATRS) is a PROM designed to assess outcomes in patients with ruptures of the Achilles tendon. The aim of this study was to develop a Norwegian adaption of the ATRS and evaluate its validity and reliability.

Methods

The ATRS was translated into Norwegian in accordance with recommended guidelines. The study included 94 patients treated for Achilles tendon ruptures from January 2010 until February 2013, and the web-based questionnaires were administered twice. Reliability was assessed by Cronbach’s alpha, the intraclass correlation coefficient (ICC) and minimal detectable change (MDC). Construct validity was evaluated by calculating the Spearman’s correlation coefficient with the five subclasses of the Foot and Ankle Outcome Score (FAOS), the SF-36 subclass physical function and the SF-36 physical and mental summary scores.

Results

Both internal consistency (Cronbach’s alpha = 0.96) and test–retest reliability (ICC = 0.90) were excellent, and the MDC was 2.12 at the group level and 16.98 at the individual level. Construct validity was supported by Spearman’s correlation coefficients above 0.7 with the SF-36 subclass physical function and the SF-36 physical summary score as well as the FAOS subclasses Sport/Rec and quality of life. There was no floor effect, and 6 patients (6.4%) achieved a maximum score of 100.

Conclusions

The Norwegian adaption of the ATRS demonstrates acceptable validity and reliability for use in the Norwegian population to assess clinical outcomes in patients with Achilles tendon ruptures.