Multifactorial monitoring of training load in elite rugby sevens players: cortisol/cortisone ratio as a valid tool of training load monitoring.

The effectiveness of selected physiological and perceptual measures for monitoring training load and fatigue was studied in 16 male elite rugby sevens players during a 6-week intense training block (IT) and 2-week tapering (TAP). Daily training load (TL) and strain (TS) as well as weekly total score of fatigue (TSF) were quantified respectively by the session-rating of perceived exertion (RPE) method and an 8-item questionnaire. Also, testing was performed and 24 h urinary cortisol (C), cortisone (Cn), adrenaline (A) and noradrenalin (NA) excretion was measured before (T0) and after the IT (T1) and after the TAP (T2). The TL, TS and TSF increased during the IT and decreased during the TAP, in conjunction with a significant drop and improvement, respectively, of performance standards during the two periods. At T1, C and Cn levels increased while A and NA levels decreased, resulting in a higher C/Cn ratio and lower A/NA ratio, respectively. At T2, both C/Cn and A/NA returned to baseline values. The changes in C/Cn ratio, after the 6-week IT, were more closely related to mean TL, TS and TSF (r=0.75-0.76 vs. r=0.48-0.58, p<0.01) and to changes in the majority of performance measures than to A/NA ratio. Only the changes in C/Cn ratio after the 2-week TAP were related to mean TL, TS and TSF (r=0.61-0.68, p<0.01). The changes in hormone levels, training strain and performance standards reflected the physical and mental stressors of training, with complete recovery, as indicated by physiological homeostasis, achieved after an appropriate tapering period.

The IGF-1/cortisol ratio as a useful marker for monitoring training in young boxers.

Training effects on plasma insulin-like growth factor-1 (IGF-1)/cortisol ratio were investigated in boxers. Thirty subjects were assigned to either the training or the control group (n = 15 in both). They were tested before the beginning of training (T0), after 5 weeks of intensive training (T1), and after 1 week of tapering (T2). Physical performances (Yo-Yo intermittent recovery test level-1), training loads, and blood sampling were obtained at T0, T1, and T2. Controls were only tested for biochemical and anthropometric parameters at T0 and T2. A significantly higher physical performance was observed at T2 compared to T1. At T1, cortisol levels were significantly increased whereas IGF-1 and insulin-like growth factor binding protein-3 (IGFBP-3) levels remained unchanged compared to baseline. At T2, cortisol levels decreased while IGF-1 and IGFBP-3 levels increased. The IGF-1/cortisol ratio decreased significantly at T1 and increased at T2, and its variations were significantly correlated with changes in training loads and Yo-Yo intermittent recovery test level 1 (IRT1) performance over the training period. Cortisol variations correlated with changes in training load (r = 0.64; p < 0.01) and Yo-Yo IRT1 performance (r = 0.78; p < 0.001) at T1 whereas IGF-1 variations correlated only with changes in Yo-Yo IRT1 performance at T2 (r = 0.71; p < 0.001). It is concluded that IGF-1/cortisol ratio could be a useful tool for monitoring training loads in young trained boxers.

Effects of recreational soccer on physical fitness and health indices in sedentary healthy and unhealthy subjects.

Recreational soccer (RS) is becoming a popular alternative to the classical continuous exercise mode used for the improvement of cardiovascular and metabolic fitness in untrained people. The objective of this paper was to conduct a detailed systematic review of the literature, identifying the physiological responses to RS and the training effects of RS on aerobic fitness and health in untrained healthy individuals and clinical patients. PubMed, Google Scholar and ScienceDirect databases were searched using terms related to recreational soccer. Inclusion criteria were randomized controlled trials (RCT) that assessed acute physiological responses to RS or the training effects of RS on physical fitness and health in sedentary, untrained subjects of any age or health status. All studies were assessed for methodological quality using the PEDro scale. Thirty-five articles met the inclusion criteria; seven examined the acute response to RS, and 28 assessed training effects. Clear evidence was found that RS had positive effects on many health-related indices and variables, including VO2max (gains of 7-16%), blood pressure (reductions of 6-13 mmHg), body composition (decreased fat mass and improved indices of bone health), and metabolic and cardiac function. These positive effects were observed in both healthy individuals and clinical patients, irrespective of age or sex. Although this review provides clear evidence of the positive effects of RS on health, most studies had limitations of methodology (an average PEDro score < 6). Furthermore, many of the training studies were from a small number of research groups. Future studies should be extended to other countries and institutions to ensure generality of the results. Regular RS training leads to significant cardiovascular and muscular adaptations and gains of health both in sedentary individuals and clinical patients at all ages, suggesting that RS is a potentially highly motivational method to enhance population health.

Improved tolerance of peripheral fatigue by the central nervous system after endurance training.

PURPOSE: The purposes of this study were to evaluate the effect of endurance training on central fatigue development and recovery. METHODS: A control group was compared to a training group, which followed an 8-week endurance-training program, consisting in low-force concentric and isometric contractions. Before (PRE) and after (POST) the training period, neuromuscular function of the knee extensor (KE) muscles was evaluated before, immediately after and during 33 min after an exhausting submaximal isometric task at 15 % of the maximal voluntary contraction (MVC) force. After training, the trained group performed another test at iso-time, i.e., with the task maintained until the duration completed before training was matched (POST2). The evaluation of neuromuscular function consisted in the determination of the voluntary activation level during MVCs, from peripheral nerve electrical (VAPNS) and transcranial magnetic stimulations (VATMS). The amplitude of the potentiated twitch (Pt), the evoked [motor evoked potentials, cortical silent period (CSP)] and voluntary EMG activities were also recorded on the KE muscles. RESULTS: Before training, the isometric task induced significant reductions of VAPNS, VATMS and Pt, and an increased CSP. The training period induced a threefold increase of exercise duration, delayed central fatigue appearance, as illustrated by the absence of modification of VAPNS, VATMS and CSP after POST2. At POST, central fatigue magnitude and recovery were not modified but Pt reduction was greater. CONCLUSION: These results suggest that central fatigue partially adapts to endurance training. This adaptation principally translates into improved tolerance of peripheral fatigue by the central nervous system.

Effects of endurance training on the maximal voluntary activation level of the knee extensor muscles.

PURPOSE: The aim of this study was to investigate the neural adaptations to endurance training, and more specifically the adaptation of the cortical voluntary activation of the knee extensor (KE) muscles. METHODS: Sixteen sedentary men were randomly allocated into an endurance training (n = 8) or a control group (n = 8). All subjects performed a maximal aerobic speed test (MAS) before and immediately after the training period. Training lasted 8 weeks and was based on endurance running. During Pre- and Post-training testing sessions, maximal voluntary contraction (MVC) was measured and voluntary activation (VA) was calculated via peripheral nerve (PNS) and transcranial magnetic stimulations (TMS) superimposed to MVC. Electromyographic activity (EMG) of the KE muscles was also measured during MVC, PNS (M-wave) and TMS (motor evoked potentials-MEP). The cortical silent period following TMS was also assessed. RESULTS: Despite a significant improvement in endurance running performance, as suggested by the increase of MAS in the training group (Pre 15.4 ± 1.6 vs. Post 16.4 ± 1.6 km·h(-1)), endurance training did not affect MVC or VA as measured with PNS and TMS. Similarly, the EMG of KE muscles during MVC did not show any significant changes. Furthermore, the MEP amplitude and the duration of the silent period also remained unchanged after endurance training. CONCLUSIONS: The present study suggests an 8-week endurance-training program does not generate adaptations of neural factors in sedentary subjects.

Reducing resistance training volume during Ramadan improves muscle strength and power in football players.

We aimed to examine the effect of maintaining or reducing resistance training volume during Ramadan-intermittent-fasting (RIF) on short-term maximal performances. 20 footballers (age: 18.4 ± 0.8 years; body-mass: 72.4 ± 4.1 kg; height: 183.4 ± 4.6 cm) were matched and randomly assigned to a normal-training-group (G1) or a tapering-group (G2). They were tested for muscular strength (maximal-voluntary-contraction) and power (squat-jump and counter-movement-jump) 1 month before RIF (T0), 1 week before RIF (T1), after 2 weeks of fasting (T2) and at the end of RIF (T3). From T1 to T2, subjects performed a whole-body resistance training program (8-repetitions × 4-sets with 4-min recovery in-between). During RIF, G1 maintained the same training program, while G2 performed a period of reduced training volume (3 sets/exercise; - 22%). Muscle strength and power increased significantly from T0 to T1, from T0 to T2 and from T0 to T3 in G1 and G2 and from T1 to T2 and from T1 to T3 only in G2 (p<0.05). Performance was higher in G2 than G1 during T2 (p<0.01). Moreover, the ∆-change of performance between T0 and T2 and T3 was significantly higher in G2 than G1 (p<0.05). For young soccer players, a tapering period characterized by a reduced training volume during RIF may lead to significant improvement in muscle strength and power.

Recovery (passive vs. active) during interval training and plasma catecholamine responses.

The effect of recovery mode (Active [AR] vs. Passive [PR]) on plasma catecholamine (Adrenaline [A] and Noradrenaline [NA]) responses to maximal exercise (Exemax) was studied during interval training (IT). 24 male subjects (21.1±1.1 years) were randomly assigned to a control group (CG, n=6), AR training group (ARG, n=9) or PR group (PRG, n=9). ARG and PRG participated in an IT program 3 times a week for 7 weeks. Before and after training, maximal oxygen uptake (VO2max) and maximal aerobic velocity (MAV) were measured. Plasma A and NA were determined at rest, at the end of Exemax and after 10 and 30 min of recovery. Training induced significant changes only in ARG: an increase of VO2max and MAV along with a significant increase of A and NA at the end of Exemax (2.82±0.15 vs. 1.03±0.15 nmol/l and 7.22±0.36 vs. 6.65±0.57 nmol/l, respectively p<0.05). The ratio A/NA measured at the end of Exemax also increased significantly after training (0.41±0.11 vs. 0.16±0.08, P>0.05). The present results show that IT with AR induces a significant increase of A and NA concentrations in response to maximal exercise. The study furthermore shows that IT program with AR may induce more stress than the same program with PR.

Specific sites of bone expansion depend on the level of volleyball practice in prepubescent boys.

The purpose of this study was to investigate the effect of 18 months of high and low levels of volleyball practice on bone acquisition. 130 prepubescent boys (mean age 11.4 ± 0.7) were divided into a high-level training group (HLG), low-level training group (LLG), and controls. Bone mineral content (BMC) and bone area at the whole body, lumbar spine L2-L4, femoral neck of the dominant leg, and right and left radius were measured using dual-photon X-ray absorptiometry. Enhanced BMC resulted from high-training volleyball activity in all measured sites except the third left and right distal radius, which is not modified by low-level training in prepubescent players but it was accompanied by a bone area expansion in radius and weight-bearing sites for the HLG, and in legs, whole right and left radius for the LLG. Significant improvement of skeletal tissues is associated with the intensity and duration of volleyball training.

[Pulmonary function in rheumatoid arthritis in a Tunisian population]. / La fonction respiratioire dans la polyarthrite rhumatoïde chez une population tunisienne.

BACKGROUND: The rheumatoid polyarthritis (PR) is a frequent pathology in Tunisia. The most frequent extra articular expression of this disease is in the respiratory tract. AIM: To determine the lung functional profile of PR of the Tunisian population by establishing possible relations between ventilatory variables and clinico-biological parameters of PR. METHODS: It is a cross sectional study which concerned 87 patients (77 women) having a confirmed PR. They benefited from a measure of the lung function by a total physical Pléthysmography and by the technique of double transfer NO-CO. Clinical and biological checkup were realized. RESULTS: Three kinds of pulmonary function defects were found: obstructive ventilatory defect (13%), restrictive defect (7%) and mixed defect (1%). Ventilatory flows and the lung volumes correlated negatively with the inflammatory syndrome (p<0.05). Alveolar-capillary diffusion capacity (DLco) was altered in an isolated way or associated with the respiratory functional syndromes (obstructive and restrictive) (6%). This abnormality had a vascular origin with an isolated fall of the lung capillary volume (Vc), a membrane origin with an isolated fall of the diffusion membrane (DM) or a combined origin with the decline of Vc and DM. This latter case was found at a late stage of PR. 58% of PR patients had a normal pulmonary function. CONCLUSION: All these functional findings were linked to PR itself (inflammatory and auto-immune origin) or to the lung toxicity due to the treatment by Methotrexate (alveolar and bronchial damage).

Six-minute walking test predicts maximal fat oxidation in obese children.

BACKGROUND: Obesity is associated with reduced exercise maximal fat oxidation rate (FATmax), which is generally assessed by cardiopulmonary cycling test. The six-minute walking test (6MWT) presents an alternative method in patients. OBJECTIVE: The aim of this study was to establish a practical reference equation facilitating the prediction of FATmax from the 6 MWT in obese children of both genders. DESIGN: This study is a cross-sectional study using mixed linear and multiple regression models. RESEARCH METHODS AND PROCEDURES: Anthropometric measurements were recorded and submaximal cycling test and 6 MWT conducted for 131 school-aged obese children, 68 boys and 63 girls. A multiple regression analysis for FATmax, including six-minute walking distance (6 MWD), anthropometric and cardiac parameters as the dependent variables, was performed for the two genders separately. RESULTS: Mean 6 MWD and FATmax were 564.9 ± 53.7 m and 126.5 ± 12.1 mg min(-1) for boys and 506.7 ± 55.0 m and 120.7 ± 10.0 mg min(-1) for girls, respectively. The 6MWD, body mass index, Z-score, fat-free mass, waist and hip circumferences (WC and HC), rest heart rate, and systolic and diastolic blood pressures were highly correlated with FATmax for both genders. There was a significant correlation between 6 MWD and FATmax in both boys and girls (r = 0.88 and r = 0.81, P<0.001, respectively). Stepwise regression analyses revealed that the combinations of 6 MWD with HC for boys and 6MWD with WC for girls improved the predictability of the model (R(2) = 0.81 for boys and R(2) = 0.72 for girls; P<0.001). CONCLUSION: In obese children, the 6MWT can be used to predict FATmax when formal test of exercise capacity and gas exchange analysis are unavailable or impractical. It is therefore possible to prescript targeted exercises at FATmax, without performing indirect calorimetry, just from a field test.

Obesity induced bronchopulmonary hyperresponsiveness in Tunisian women.

OBJECTIVE: The specific objective of this investigation was to determine whether bronchopulmonary responsiveness (BPR) to methacholine (MCH) was associated with the body mass index (BMI) of Tunisian women. SUBJECTS: In all, 160 healthy nonsmoker women (52 lean, 45 overweight and 63 obese) were recruited and examined in the Clinical Laboratory of Physiology located in the Medical School of Sousse. The average ages (+/-s.e.) of the three categories of lean, overweight and obese subjects were 27.7+/-1.1, 33.2+/-1.7 and 37.5+/-1.3 years, respectively. Their corresponding mean BMIs (+/-s.e.) were 21.9+/-0.3, 27.7+/-0.2 and 36.5+/-0.8 kg m(-2), respectively. MEASUREMENTS: Before their inclusion into the study, subjects were screened for their lung status by measuring their pulmonary function testing parameters using a whole body plethysmograph. BPR was assessed, using a cumulative concentration response curve technique, by measuring with a spirometer the decrease in forced expiratory volume in 1 s (FEV(1)) in response to a cumulative dose of MCH. RESULTS: After adjusting for age, significant differences in both FEV(1) and forced vital capacity (VC) were found between the obese and lean groups (P<0.01), as well as between the obese and overweight groups (P<0.01). In addition, forced expiratory flow between 25 and 75% of VC was significantly different between the obese and lean groups (P<0.001), as well as between the lean and overweight groups (P=0.015). The mean maximum fall of FEV(1) in response to MCH challenge was significantly higher for the obese group (12.0%) than for the overweight (9.8%) or the lean (6.6%) group (P<0.01). Furthermore, the efficacy of the MCH agonist promoting the maximal response (E(max)) and its potency or effective dose producing 50% of the maximal response (ED(50)) were both associated with BMI (the higher the BMI, the higher the E(max) and the lower the ED(50)). CONCLUSION: Our data clearly show that obesity affects pulmonary function performance in Tunisian women by potentially promoting their bronchial hyperreactivity as suggested by the significant correlation between their BMI and the efficacy of the MCH, as well as its potency.

Obesity-induced impairment of endothelium-dependent vasodilation in Tunisian women.

OBJECTIVE: It is now well recognized that obesity is a major public health concern, and its prevalence has tremendously increased worldwide over the last decades, including Tunisia. As obesity is associated with cardiovascular diseases, the purpose of this study was to investigate the effect of obesity on forearm skin blood flow (FSBF) response to acetylcholine (Ach), an endothelium-dependent vasodilator, in Tunisian women over a wide range of body mass indices (BMIs). SUBJECTS: One hundred and eighty healthy women with an average age of 34+/-6 years, an average height of 162+/-7 cm and an average weight of 78+/-19 kg participated in this investigation. The mean BMIs of the 60 lean, 50 overweight and 70 obese subjects were 22.1+/-0.3, 27.7+/-0.2 and 38.4+/-0.7 kg m(-2), respectively. MEASUREMENTS: The FSBF was measured non-invasively using a laser Doppler flowmeter in response to local infusion of a cumulative dose of Ach. RESULTS: After adjusting for age, the mean response of FSBF to Ach was significantly greater in lean (1168%+/-78) than in overweight (643%+/-38) and obese subjects (323%+/-18) (P=0.002; P<0.0001, respectively), suggesting a reduction of the endothelium-dependent nitric oxide (NO) release by obesity. Our regression analysis also revealed that the maximum FSBF response to Ach (that is, its efficacy) was inversely correlated with BMI, waist and hip circumferences (r=-0.994, P=0.002; r=-0.2, P<0.0001, and r=-0.321, P=0.001, respectively). CONCLUSION: Our data demonstrate a reduction of skin vasodilatory reserve in obese patients and suggest a defect of both endothelial-dependent relaxation and wall compliance associated with obesity.

Exercise improves the ApoB/ApoA-I ratio, a marker of the metabolic syndrome in obese children.

AIM: This study was designed to examine the effect of training on components of the metabolic syndrome and ApoB/ApoA-I ratio in obese children. METHODS: We studied thirty-two obese children (13.3 ± 0.4 years) with 16 subjects who participated to 8-week training and 16 subjects serving as a control group. Training was individualized at the point where fat oxidation was maximal (Fat max). In each subject, pre- and postintervention anthropometric measures and biochemical tests on fasting blood were performed. RESULTS: After the programme, the training group showed an increase in VO(2peak) and fat oxidation during exercise. Body mass index (BMI), blood glucose and triglycerides were reduced, and high-density lipoprotein (HDL) was increased. ApoB/ApoA-I ratio decreased significantly (-0.43%, p < 0.01). Systolic and diastolic blood pressure also decreased (-8.4% and -10.9%, respectively). Among the training group, 10 subjects were classified as having the metabolic syndrome before the intervention and none after. No significant changes in any other variables were measured in the control group. CONCLUSIONS: Training targeted at Fat max reduces the prevalence of metabolic syndrome and its associated factors in obese children. In particular, this intervention decreases the ApoB/ApoA-I ratio, which may be considered as a marker for following this syndrome.

Review on leptin and adiponectin responses and adaptations to acute and chronic exercise.

Leptin and adiponectin represent two newly discovered adipose tissue derived hormones; that are both associated with health status and glucose and free fatty acid (FFA) metabolism. Moreover, acute and chronic exercises affect body composition, carbohydrate and lipid metabolism. It is thus interesting to evaluate the effects of physical exercise and training on leptin and adiponectin levels. It seems that leptin concentration is not modified after short-term exercise (<60 min) or exercise that generates an energy expenditure lower than 800 kcal. Leptin levels decrease after long-term exercise (> or =60 min) stimulating FFA release, or after exercise that generates energy expenditure higher than 800 kcal. Adiponectin concentration presents a delayed increase (30 min) after short-term intense exercise (<60 min) performed by trained athletes. For adiponectin, limited data suggest that adiponectin concentration presents a delayed increase (30 min) after short-term intense exercise (<60 min) performed by trained athletes. It seems that adiponectin concentrations do not change in response to long-term exercise (> or =60 min). Short-term training (<12 weeks) and long-term training (> or =12 weeks) show contrasting results regarding leptin and adiponectin. Most training studies which improve fitness levels and affect body composition could decrease leptin and increase adiponectin concentrations.

Adiponectin responses to acute moderate and heavy exercises in overweight middle aged subjects.

AIM: The purpose of this study was to investigate the effect of acute moderate and heavy exercises on adiponectin, leptin and insulin concentrations in untrained subjects. METHODS: Seven overweight middle-aged males participated in this study (age: 36.00 ± 5.16 years; body weight: 93.94 ± 6.48 kg; percent body fat: 26.64 ± 2.75%; Body Mass Index: 28.32 ± 1.74 kg.m2). They took part in two sub-maximal cycling exercises; moderate; 20 min cycling at 60% of peak aerobic power (PAP) and heavy: 20 min cycling at 80% of PAP. Venous blood samples were obtained before, after 30, 60 and 90 min recovery. RESULTS: Adiponectin concentrations were unchanged (P>0.05) after exercises. However, leptin was significantly decreased under resting values after 30 min (-12.74%, P=0.0023), 60 min (-11.66%, P=0.0084) and 90 min (-8.42%, P=0.0023) after the heavy exercise. Similarly, insulin was lowered after 90 min after the heavy exercise (-55.96%, P=0.014). Basal adiponectin during moderate exercise was significantly and negatively related to BMI (r=-0.778, P=0.033) and percent body fat (r=-0.897, P=0.0061). CONCLUSION: In conclusion our results suggested that 20 min moderate or heavy sub-maximal exercises not stimulate the production and the release of adiponectin during 1.5 hour recovery post-acute exercises. Furthermore, it appears that after acute heavy exercise adiponectin is not associated with leptin or/and insulin modifications.

Establishment of reference serum insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels of Tunisian children during childhood and adolescence.

BACKGROUND: The aim of the present study is to establish age- and sex-related reference ranges of serum IGF-I and IGF binding protein-3 (IGFBP-3) levels in a pattern of Tunisian children. SUBJECTS AND METHODS: Two hundred healthy Tunisian children (103 boys and 97 girls), aged between 6 and 16 yr, were considered in the study. RESULTS: Mean serum levels of IGF-I and IGFBP-3 are observed to be higher in girls compared to boys of the same age interval. However, these differences were statistically significant only in pubertal ages (11-14 yr) for IGF-I and in pre-pubertal ages (6-10 yr) for IGFBP- 3 (p<0.05). Steeper variations in IGF-I concentrations were obtained earlier in girls than in boys (11-12 vs 12-13 yr, Tanner stage 3-4). Peak of IGF-I levels are observed at almost the same age interval (12-14 yr). IGFBP-3 levels significantly increased at steeper variations of IGF-I for both sexes followed by steady values. CONCLUSIONS: Variations of IGF-I and IGFBP- 3 with the considered parameters (sex, age, and puberty stage), which concord with previous studies on various populations, emphasize the importance of locally established reference levels to construct a SD score prediction model. Establishment of reference serum IGF-I and IGFBP-3 ranges during childhood and adolescence in Tunisian subjects can help to enhance the diagnostic efficiency of IGF-I and IGFBP-3 in evaluating growth disorders in our population.

Effect of individualized weight-loss programmes on adiponectin, leptin and resistin levels in obese adolescent boys.

AIM: We investigate the effects of a 2-month weight-loss programme on plasma levels of adiponectin, leptin and resistin in obese adolescent boys. METHODS: Twenty-one obese adolescent boys (BMI = 30.8 +/- 3.2 kg/m(2)) completed the weight-loss programme including: 1/ either energy restriction (R), 2/ or individualized exercise training at the point of maximum lipid oxidation (Lipox(max)) (E), 3/ or energy restriction and training (RE). Body composition, lipid oxidation and plasma levels of adiponectin, leptin and resistin were measured before and after intervention. RESULTS: Following the weight-loss programme, adolescents of the RE group showed an improvement of their body composition (p < 0.01), an increase in plasma adiponectin (+73.7%, p < 0.01) and a decrease in plasma leptin (-38.8%, p < 0.01) leading to an increase in adiponectine/leptin ratio (ALR, +144.4%, p < 0.01) higher than the R or E groups. E and RE groups only showed a similar significant increase in plasma resistin (p < 0.05) and a significant improvement of lipid oxidation rate at Lipox(max) (p < 0.01 and p < 0.001). In addition, in RE group, ALR is correlated with waist/hip and waist/height ratios, resistin level, homoeostasis mode assessment (HOMA-IR) index and Lipox(max). CONCLUSION: In obese adolescents boys, moderate exercise training completed at Lipox(max) and combined with energy restriction improves their ability to oxidize lipids, which is associated with a normalization of their adiponectin, leptin and resistin levels resulting in an improved insulin sensitivity, as attested by a higher ALR and a lower HOMA-IR.

Two-month effects of individualized exercise training with or without caloric restriction on plasma adipocytokine levels in obese female adolescents.

OBJECTIVES: To examine if, in young obese patients, an individualized training programme in association with a caloric restriction programme which had an effect on whole-body lipid oxidation, was able to induce changes on plasma adipocytokine concentrations. MATERIALS AND METHODS: Twenty-seven obese female adolescents participated in the study. Whole-body lipid oxidation during exercise was assessed by indirect calorimetry during a graded cycle ergometer test. Body mass (BM), body mass index (BMI), percentage of body fat (%BF), insulin homeostasis model assessment (HOMA-IR) and fasting levels of circulating adipocytokines were assessed prior and after a two-month diet programme, individualized training programme targeted at Lipox(max) corresponded to the power at which the highest rate of lipids was oxidized and combined diet/training programme. RESULTS: The diet/training programme induced both a shift to a higher-power intensity of Lipox(max) (+27.8 + or - 5.1 W; p<0.01) and an increase of lipid oxidation at Lipox(max) (+96.8 + or - 16.2mg/min; p<0.01). The enhancement in lipid oxidation was significantly (p<0.01) correlated with the diet/training-induced improvement in %BF (r = -0.47), HOMA-IR (r = -0.66), leptin (r = -0.41), TNF-alpha (r = -0.48), IL-6 (r = -0.38), adiponectin (r = 0.43) and resistin (r = 0.51). CONCLUSION: This study showed that in obese female adolescents a moderate training protocol targeted at Lipox(max) and combined with a diet programme improved their ability to oxidize lipids during exercise, and that this improvement was associated with changes in plasma adipocytokine concentrations.

[Determining factors of pulmonary function in healthy Tunisian children]. / Déterminants de la fonction pulmonaire chez l'enfant sain en Tunisie.

Introduction Pulmonary function parameters are known to vary with age, sex, height and ethnic extraction. No normal values have been reported for pulmonary function in Tunisian children. Moreover, little attention has been paid to the factors affecting the development of lung function in Tunisian healthy children. State of art Birth weight and height, physical activity level, anthropometric, socioeconomic and environmental factors could influence the development of lung function in healthy children. Perspectives The studies conducted by our group have allowed us 1) to set reference values for spirometry in healthy Tunisian children; 2) to indicate that, in Tunisian adolescents, the use of only one morphological parameter such as height, is not sufficient, but the pubertal status could be taken into account to standardize the lung function and 3) to show the main predictive factors for pulmonary development to be the anthropometric factors such as height, weight, maximal inspiratory and expiratory thoracic perimeter, sex and age, and the environmental conditions (type of heating) in our population of healthy Tunisian children. Conclusion These findings should improve medical surveillance of respiratory diseases, stipulation of preventive and therapeutic measures in Tunisian children.

[Spirometric profile of narghile smokers]. / Profil spirométrique des fumeurs de narguilé

INTRODUCTION: Studies of the spirometric profile of narghile smokers are few, have some methodologic limits (ie. small sample size) and present contradictory conclusions. OBJECTIVE: (i) To determine the percentage of smokers having an obstructive ventilatory defect (OVD) and/or a restrictive ventilatory defect (RVD) or static hyperinflation (SHI). (ii) To compare the chronological and the estimated lung ages. INCLUSION CRITERIA: men aged 20-60 years smoking narghile (>1 narghile-year (NA). Non-inclusion criteria: cigar or cigarettes smoker and co-morbidity. Narghile consummation quantification: NA and kg of cumulated tobacco (1 NA=9.125 kg of cumulated tobacco). DEFINITIONS: large airway OVD: FEV1/FVCLLN and forced mid expiratory flowupper limit of normal. Spirometric measures (Vmax 22 Series/6200 Autobox, Yorba Linda, California, USA with measurement of functional residual capacity by nitrogen washout). Measurements were made according to international recommendations. RESULTS: 110 narghile smokers were included (34+/-10Yr; 1.76+/-0.07m; 84+/-14kg). 36% of subjects had SHI; 14% had small airway OVD; 14% had RVD and 6% had large airway OVD. (ii) Estimated lung age was higher than the chronological lung age (47+/-18Yr vs 34+/-10Yr, p<0.05). CONCLUSION: Narghile consumption accelerates ageing of the lung. This study provides the health authorities with valid arguments to fight this blight on society which increasingly involves children and pregnant women.