Influence of resistance training and herbal supplementation on plasma apelin and metabolic syndrome risk factors in postmenopausal women.

Purpose ­: Menopause is a normal condition that all women experience as they age. The aim of this study was to assess the effects of circuit resistance exercise training with Zataria multiflora (Avishan-e-Shirazi) dietary supplementation on plasma apelin, glucose, insulin, insulin sensitivity and insulin resistance. Methods ­: Ninety-six volunteer postmenopausal women were allocated into 8 groups. Resistance training consisted of 12 stations had been done for 8 weeks. Blood samples were collected at pre- and -post intervention. Results ­: Circuit RT increases apelin and decreases both insulin and blood glucose, whereas Zataria multiflora has no independent effect on apelin but does decrease blood glucose and is likely to be in some means synergistic with circuit RT effects. Conclusion ­: These results suggest that circuit resistance training augments plasma apelin and decreases both insulin and blood glucose. However, Zataria multiflora has no independent effect on apelin but does decrease blood glucose which is likely to be to some extent synergistic with training effects.

Objectif ­: La ménopause est une situation physiologique qui affecte toutes les femmes autour de la cinquantaine. Le but de cette étude était d'évaluer les effets d'un entraînement en résistance de type « circuit training ¼ avec supplémentation orale en Zataria multiflora (Avishan-e-Shirazi) sur l'apeline plasmatique, le glucose, l'insuline, la sensibilité à l'insuline et la résistance à l'insuline. Méthodologie ­: Quatre-vingt quatre femmes postménopausées bénévoles ont été réparties en 8 groupes. L'entraînement en circuit training comprenait 12 séances sur 8 semaines. Des échantillons sanguins ont été prélevés avant et après intervention. Résultats ­: Le circuit training augmente l'apeline et diminue à la fois l'insuline et la glycémie, alors que Zataria multiflora n'a pas d'effet indépendant sur l'apeline, mais diminue la glycémie et est semble synergique des effets du circuit training. Conclusion ­: Ces résultats suggèrent que le circuit training augmente l'apeline plasmatique et diminue insuline et glucose dans le sang. Cependant, Zataria multiflora n'a pas d'effet indépendant sur l'apeline mais fait diminuer la glycémie, ce qui est susceptible d'être dans une certaine mesure synergique avec les effets de l'entraînement.

Effects of Recovery Mode during High Intensity Interval Training on Glucoregulatory Hormones and Glucose Metabolism in Response to Maximal Exercise.

Catecholamines [adrenaline (A) and noradrenaline (NA)] are known to stimulate glucose metabolism at rest and in response to maximal exercise. However, training and recovery mode can alter theses hormones. Thus our study aims to examine the effects of recovery mode during High-intensity Interval Training (HIIT) on glucoregulatory hormone responses to maximal exercise in young adults. Twenty-four male enrolled in this randomized study, assigned to: control group (eg, n=6), and two HIIT groups: intermittent exercise (30 s run/30 s recovery) with active (arg, n=9) or passive (prg, n=9) recovery, arg and prg performed HIIT 3 times weekly for 7 weeks. Before and after HIIT, participants undergo a Maximal Graded Test (MGT). Plasma catecholamines, glucose, insulin, growth hormone (Gh) and cortisol were determined at rest, at the end of MGT, after 10 and 30 min of recovery. After training V02max and Maximal Aerobic Velocity (MAV) increased significantly (p<0.05) in arg. After HIIT and in response to MGT plasma glucose increase significantly (p=0.008) lesser in arg compared to prg whereas insulin concentrations were similar. The glucose/insulin ratio was significantly lower at MGT end (p=0.033) only in arg after training. After HIIT, in response to MGT, plasma A, NA, cortisol and Gh concentrations were significantly higher only in arg (p<0.05). HIIT using active recovery is beneficial for aerobic fitness, plasma glucose and glucoregulatory hormones better than HIIT with passive recovery. These findings suggest that HIIT with active recovery may improve some metabolic and hormonal parameters in young adults.

Redox Status of Professional Soccer Players is Influenced by Training Load Throughout a Season.

The purpose of this study was to follow-up the variation of pro-/antioxidant status throughout a whole season in elite professional soccer players from the French league (n=19, 18.3±0.6 years) and to examine a possible link between these variations and training load. 5 time points (T1, T2, T3, T4, T5) were proposed to surround crucial periods of training during the whole season: the pre-season training/mid-season periods (T1-T2 and T3-T4), the championship or in-season periods (T2-T3 and T4-T5). At these times, blood samples were collected to measure pro-/antioxidant status (in erythrocytes: the ratio of reduced glutathione/oxidized glutathione, superoxide dismutase and glutathione peroxidase activities, in plasma: alpha-tocopherol, beta-carotene), and dietary intakes were also recorded. Training loads were quantified by the rating of perceived exertion method weekly throughout the season. Pro-/antioxidant-related measurements showed no modifications except for GSH/GSSG ratio, which evolved significantly between season periods: from 36.43±4.15 (T1) to 115.99±16.43 (T2) to 91.64±21.24 (T3) to 202.29±29.26 (T4) to 59.61±14.61 (T5). We observed a significant correlation (r(2)=0.84) between changes in GSH/GSSH ratio and cumulated mean training loads. In conclusion, these results suggest that the redox status of professional soccer players is altered according to training period (in-season periods) and that GSH/GSSH ratio variations are correlated with cumulated training loads.

Influence of playing style on the physiological responses of offensive players in table tennis.

AIM: The study aimed to analyse the influence of playing style on the physiological responses of offensive players and on match characteristics during table tennis matches. METHODS: Eight table tennis players were involved in the study. Among them, six players with an offensive playing style (Off) played respectively two matches: one against an offensive player (Off vs. Off matches) and the other one against a defensive opponent (Off vs. Def matches). Duration of rally (DR), real playing time (RPT), effective playing time (EPT), frequency of shots by minutes, and shots per rally were measured. Heart rate (HR) was monitored continuously while rating of perceived exertion (RPE) was obtained after each match. Blood lactate concentrations ([La]) were measured both at the end of each set and at the end of the match. RESULTS: DR (5.4±0.7 s vs. 3.2±0.4 s), RPT, EPT (31.8±5.0% vs. 20.3±1.7%), shots per rally (6.6±0.9 vs. 4.6±0.9), HRmean (146.0±5.9 bpm vs. 139.9±9.0 bpm), HRmean relative to the predicted maximal HR (HRmax-p) (74.8±4.0% vs. 71.7±4.3%) and RPE (7.0±1.1 vs. 5.5±1.5) were significantly higher (P<0.05) in Off vs. Def matches. No significant differences (P>0.05) for HRpeak, [La]mean and [La]peak were noticed between Off vs. Def matches and Off vs. Off matches. CONCLUSIONS: Table tennis playing style influences match characteristics and the offensive player's physiological responses.

Effects of high vs. moderate exercise intensity during interval training on lipids and adiponectin levels in obese young females.

PURPOSE: We investigate the effects of 12-week interval training of moderate- or high-intensity exercise on blood lipids and plasma levels of adiponectin. METHODS: Thirty-four obese adolescent females [age = 15.9 ± 0.3 years; BMI and BMI-Z-score = 30.8 ± 1.6 kg/m(2) and 3 ± 0.3, respectively], were randomized to high-intensity interval training (HIIT, n = 11), moderate-intensity interval training (MIIT, n = 11), or a control group (CG, n = 12). Maximal oxygen uptake ([Formula: see text]), maximal aerobic speed (MAS), plasma lipids and adiponectin levels were measured in all subjects before and after training. RESULTS: Following the training program, in both training groups, body mass, BMI-Z-score, and percentage body fat (% BF) decreased, while [Formula: see text] and MAS increased. Low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and adiponectin levels were positively altered (-12.6 and -7.4 %; 6.3 and 8.0 %; 35.8 and 16.2 %; high to moderate training program, respectively). Waist circumference, triglyceride and total cholesterol decreased only in HIIT group (-3.5; -5.3 and -7.0 %, respectively, in all P < 0.05). Significant decrease in the usual index of insulin resistance (HOMA-IR) occurred in HIIT and MIIT groups (-29.2 ± 5.3 and -18.4 ± 8.6 %, respectively; P < 0.01). CONCLUSION: The results show that HIIT positively changes blood lipids and adiponectin variables in obese adolescent girls, resulting in improved insulin sensitivity, as attested by a lower HOMA-IR, and achieving better results compared to moderate-intensity exercise.

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.

Effect of an individualized physical training program on resting cortisol and growth hormone levels and fat oxidation during exercise in obese children.

OBJECTIVES: The aim of this study was to characterize the resting levels of cortisol and growth hormone (GH), and the substrate profile during exercise of obese children before and after an individualized training program. PATIENTS AND METHODS: Twenty-two obese children (13.1 ± 0.8 yrs) were included in the study. Twelve individuals (six boys and six girls; 31.1 ± 1.1 kg/m², VO2(peak)=1.92 ± 0.16l/min) participated in a two-month endurance training program and 10 individuals (five boys and five girls; 30.9 ± 1.7 kg/m², VO2(peak)=1.98 ± 0.12l/min) served as controls. Training was individualized and targeting at the point were fat oxidation was maximal (Lipox(max)). Substrate oxidation was evaluated by indirect calorimetry. To determine plasma cortisol and GH concentrations, blood was collected at rest before and after the two-month period. RESULTS: Before the program, no significant differences were detected between the training group and the control group for any of the measured anthropometric, metabolic or hormonal variables. At the end of the two-month program, training group showed an increase in VO2(peak) and fat oxidation during exercise. After the program, resting levels of GH and cortisol were significantly increased in the training group (+0.9 ± 0.3 ng/mL and +55.4 ± 10.3 ng/mL respectively, p < 0.01). Following the two-month period, there was no change in any variables measured in control group. CONCLUSION: The present data show that an individualized endurance training program targeting Lipox(max) improves fat oxidation during exercise and increases resting levels of GH and cortisol.

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.

Obesity and catecholamine responses to maximal exercise in adolescent girls.

The aim of this study was to investigate plasma catecholamine [adrenaline (A) and noradrenaline (NA)] concentrations at rest and in response to maximal exercise in three different groups of adolescent girls. According to their body mass index, 34 adolescent girls aged 15-16 years were divided into three groups: a normal weight group (NO) (n = 11), an overweight group (OW) (n = 11) and an obese group (OB) (n = 12). Plasma A and NA concentrations were measured at rest during fasting conditions (A(0) and NA(0)), after a standardized breakfast (A(rest) and NA(rest)) and immediately after an incremental exhaustive exercise (A(EX) and NA(EX)). A (0) and NA(0) were not significantly different among the three groups. However, the A(0)/NA(0) was statistically lower in OB compared to OW and NO. A(EX) and NA(EX) were significantly higher than resting values in the three groups. However, in response to exercise, no significant differences were reported between OB (A(EX) = 2.20 +/- 0.13 nmol/l, NA(EX) = 12.28 +/- 0.64 nmol/l), OW (A(EX) = 2.39 +/- 0.23 nmol/l, NA(EX) = 12.94 +/- 0.93 nmol/l) and NO (A(EX) = 2.52 +/- 0.24 nmol/l, NA(EX) = 12.60 +/- 0.63 nmol/l). In conclusion, our results showed that at rest, in adolescent girls, the responsiveness of the adrenal medulla to the sympathetic nervous activity is lower in OB subjects compared to OW and NO ones. However, in response to maximal exercise, plasma catecholamines are not affected by obesity.

Androgen responses to sprint exercise in young men.

The purpose of this study was to investigate the effects of a 6-month sprint training program on plasma androgens and catecholamine (CA) concentrations in response to a 6 s sprint in adolescent boys [training group (TG), n=6; control group (CG), n=6]. A 6 s-sprint test was performed on a cycle ergometer before and after training (Pre-T and Post-T, respectively). Plasma total testosterone (TT), bioavailable testosterone (BT), and CA concentrations were measured at rest, after a warm-up, immediately after a 6 s-sprint, and during the recovery (i. e. 5 and 20 min). After training period, plasma TT concentrations increased significantly at the end of the sprint and during the recovery in the TG. No effects for sampling times and period were observed in BT levels. Plasma TT concentrations after 5 min of recovery were positively correlated with the corresponding values of plasma lactate (La) concentrations and with post-6 s-sprint plasma adrenaline (A) concentrations (r=0.52; p<0.01 and r=0.61; p<0.01, respectively). These results suggest that sprint training increases plasma TT concentrations in response to sprint exercise in adolescent boys. Plasma A and plasma La concentrations increases in response to sprint exercise could be involved in this elevation of plasma TT concentrations.

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.

Athletic performance and weight changes during the "Marathon of Sands" in athletes well-trained in endurance.

The purpose of this study is to examine the effects of the "Marathon of Sands" (MS), a 7-day, self-sufficient-diet, multi-stage running race across a section of the Moroccan desert, on body weight and plasma volume variation (PVV) and the relationship of these factors to performance in athletes who are well-trained in endurance. Sixteen MS runners agreed to participate in this study. Weight and body composition were measured and venous blood samples were taken before the first stage (D0), after the third stage (D3) and at the end of the MS (after the sixth stage: D6). Haematocrit and haemoglobin were used to calculate PVV at (D0, D3, and D6). No significant plasma volume decrease was observed throughout the race. Significant decreases in total body weight (BW), fat-free mass (FFM) and fat mass (FM) were observed in D3 and D6 (-4.3%, -3.5%, -0.8%; and -6.1%, -5%, -1.1%, respectively, for BW, FFM and FM at D3 and D6). This study clearly shows that, despite extreme conditions, the MS did not lead to a significant PV decrease in athletes well-trained in endurance. This study also supports the hypothesis that significant body weight loss may not systematically affect performances during long duration multiple-stage races.

Effect of training and detraining on catecholamine responses to sprint exercise in adolescent girls.

Training is well known to influence catecholamine responses to exercise. In women, this training effect is still not well characterized and has been studied mostly in adults. Hence, we investigated in this longitudinal study, the effects of a 6-month sprint training program followed by 5 months of detraining on plasma catecholamine responses to a sprint exercise in young female subjects. Twelve healthy adolescent girls [training group (TG), n=6; control group (CG), n=6] took part in our study. TG participated in 6 months of supervised sprint training program (3 days/week) and has no training past whereas, CG continued with it's normal activity. A 6s-sprint test was performed on a cycle ergometer before training (P1) and after training (P2) in both the groups. TG only realized a 6s-sprint test after 5 months of detraining (P3). Blood lactate concentrations (La) as well as plasma adrenaline (A) and noradrenaline (NA) concentrations were measured at rest, immediately after the warm-up and the 6s-sprint and during recovery. Peak power W peak), expressed both in absolute and relative values, were significantly increased in TG in P2 (P<0.01) but did not change in CG. After the sprint-training period, the warm-up and the 6s-sprint induced plasma A increase and the maximal A concentrations were significantly higher than in P1 and P3 for TG only (P<0.05). Plasma A did not change in CG after 6 months. In P3, W peak and maximal lactate concentrations ([La]max) were significantly greater compared to P1 and P2 in TG (P<0.05). In CG, [La]max were significantly increased in P2 (P<0.05). The present study demonstrates that 6 months of sprint training in adolescent girls induce both an increase in performances and in A responses to sprint exercise. This adrenergic adaptation disappears after 5 months of detraining whereas the gain in performance is maintained. These new data may lead to practical considerations.

Effect of sprint duration (6 s or 30 s) on plasma glucose regulation in untrained male subjects.

AIM: We have explored in the following study the glucoregulatory responses (glycemia, insulinemia, catecholamines) at the end of 2 supramaximal tests of different durations. METHODS: Seven untrained male subjects (21.9+/-0.3 y) performed an isolated exercise of 6 s (T6) and a Wingate-test of 30 s. To determine the levels of lactate (La), plasma concentrations of glucose, insulin, adrenaline (A) and noradrenaline (NA), blood samples have been collected successively at rest, after a warm-up period of 15 min, immediately after T6 and T30, and after 5, 10, 20, and 30 min of recovery. RESULTS: Whether expressed as absolute or relative values, the peak power recorded during the 2 tests is statistically the same in T6 and T30. The maximal value of lactate (L(amax)) measured 5 min after the end of the 2 exercises is significantly greater after T30 (12.3+/-0.9 mmol x L(-1)) than after T6 (5.4+/-0.4 mmol x L(-1)) and T30 (4.2+/-0.2 mmol x L(-1)). No significant difference is observed between the plasma glucose concentrations recorded after the 2 tests until the first 10 min of recovery. However the plasma glucose values recorded after 20 and 30 min of recovery are significantly higher after T6 than after T30. Whatever the duration of the test, the insulinemia level remains unchanged at the end of the exercise and during the 30 min of recovery. On the other hand, the values of adrenaline and noradrenaline after T6 and T30 become considerably higher than those recorded at rest. However, the increase remains significantly higher after T30 (13.5+/-1.8 nmol x L(-1) for NA and 2.7+/-0.7 nmol x L(-1) for A) than after T6 (4.9+/-0.3 nmol x L(-1) for NA and 1.2+/-0.2 nmol x L(-1) for A). CONCLUSION: These results suggest that the mechanism responsible for increasing blood glucose surpass those which decrease it during supramaximal exercise. However, plasma glucose concentrations is affected by the duration of supramaximal exercise. The lower increase of plasma glucose concentration after T30 than after T6 might be explained by the resting of muscle glycogen stores which are more used during T30 than after T6, but in the absence of muscle glycogen content measurement we cannot conclude.

Training status (endurance or sprint) and catecholamine response to the Wingate-test in women.

The aim of this study was to verify if, as for men, training status induces different catecholamine responses to exercise. To do this, we investigated the effect of training status (sprint or endurance) on plasma catecholamine response to a supramaximal exercise in women. Nineteen subjects took part in our study: six untrained subjects (UT), seven endurance trained subjects (ET) and six sprint trained ones (ST). The trained subjects (ET and ST) were all competing at a high national level. The maximal power (W max ) and the mean power (W) were determined from the Wingate-test. Blood lactate, adrenaline (A) and noradrenaline (NA) were analysed at rest (La 0, A 0 and NA 0 ), immediately at the end of the exercise (A max and NA max ) and after 5 min recovery (La max [3 min in arterialized blood], A 5 and NA 5 ). The disappearance of A and NA was judged by the ratio (A max -A 5 )/A max and (NA max -NA 5 )/NA 5. The ratio A max /NA max was considered as an index of the adrenal medulla responsiveness to the sympathetic nervous activity. As expected, during the Wingate-test ST exhibited significantly higher performances compared to UT and ET. But in contrast to the men's data no difference was observed between the three groups both for La max (13.1 +/- 0.8 mmol x L (-1); 14.8 +/- 1.0 mmol x L (-1) and 11.2 +/- 0.5 mmol x L (-1) respectively for ET, ST and UT), NA max (22.1 +/- 1.2 nmol x L (-1); 13.1 +/- 2.4 nmol x L (-1) and 20.2 +/- 7 nmol x L (-1)respectively for ET, ST and UT) and A max (4.1 +/- 0.8 nmol x L (-1); 2.6 +/- 0.6 nmol x L (-1); 13.1 +/- 0.6 nmol x L (-1) respectively for ET, ST and UT). Consequently the ratio A max /NA max was similar in UT, ET and ST (respectively 0.2 +/- 0.03; 0.2 +/- 0.04; 0.17 +/- 0.04), These results indicated, in contrast to the men's data, that the catecholamine response to the Wingate-test did not differ between female subjects of different status of training. In conclusion this study did not find any significant effect of training status on the catecholamine response to supramaximal exercise and so argues in favour of sex differences in response to training.

Effect of training status on the sympathoadrenal activity during a supramaximal exercise in human.

BACKGROUND: The study investigated the concentrations of plasma catecholamine, adrenaline (A) and noradrenaline (NA), and the adrenal medulla responsiveness to the sympathetic nervous activity in sprinters (S), endurance runners (E) and untrained subjects (U) during a supramaximal exercise (the Wingate-test). METHODS: A group of 19 men took part in the tests: 6 S (20.5+/-0.7 years), 6 E (21.0+/-1.0 years) and 7 U (20.9+/-0.4 years). The maximal power (Wmax) and the mean power (W) were determined from the Wingate-test on a cycle ergometer. The plasma lactate, A and NA were analysed at rest (La0, A0 and NA0), immediately at the end of the exercise (Amax and NA(max)) and after 5 min recovery (La(max), A5 and NA5). The disappearance of A and NA was judged by the difference between the maximal values and those determined after 5 min recovery (Amax-A5 and NA(max)-NA5) and the ratio A/NA was considered as an index of the adrenal medulla responsiveness to the sympathetic nervous activity. RESULTS: During the Wingate-test S exhibited higher performances and higher La(max) than the two other groups. At the end of the Wingate-test the NA(max) values were similar in the three groups whereas the Amax values were significantly higher in S than in E and U (8.00+/-0.5 nmol x l(-1) in S vs 3.47+/-0.30 nmol x l(-1) and 3.29+/-1.14 nmol x l(-1) respectively in E and U). This leads to a higher Amax/NA(max) ratio for S compared to the other two groups (0.77+/-0.10 in S vs 0.23+/-0.03 and 0.28+/-0.05, respectively in E and U). As the disappearance of A (Amax-A5) was significantly higher in S (6.80+/-0.47 nmol x l(-1) in S vs 2.64+/-0.19 nmol x l(-1) and 1.64+/-1.37 nmol x l(-1), respectively in E and U), the higher values of Amax in S could be explained by an increase of the adrenal medullary secretory capacity in this group. CONCLUSIONS: It was concluded that essentially short term and intense exercises as sprint ones or interval-training may alter the adrenal medulla responsiveness to supramaximal exercise but not long duration exercises.

Physiological profile of handball players.

BACKGROUND: The purpose of this study was to determine the physiological profile of handball players compared to sprinters, endurance trained and untrained subjects. METHODS: Forty-six subjects aged between 19 and 28 years took part in this study: 10 were national handball players (NHB); 7 were international handball players (IHB), 11 were sprint trained subjects (ST); 8 were endurance trained subjects (ET); and 10 were untrained subjects (UT). They performed an incremental treadmill test to determine the maximal oxygen uptake (VO2max), and a Wingate anaerobic test (WanT) to determine maximal power (Wmax). Plasma lactate (La) concentration was measured 5 minutes after the end of the Wingate-test. RESULTS: The VO2max of NHB was similar to that of the IHB and ST athletes but higher than that of the untrained and lower than the endurance trained athletes. Values for Wmax were similar in the IHB and NHB groups and very close to the sprinters. When normalized for body mass or to lean body mass, Wmax was greater in handball players when compared to untrained or endurance trained subjects. Lactate values were in the same range in the NHB, IHB and ST groups and were statistically higher in the NHB and IHB groups than in the UT or ET groups. CONCLUSIONS: The results suggest that the anaerobic metabolism seems to be important for the handball players similarly to sprinters. Since handball is known as a sport with typically short exercise periods of high intensity alternating with rests, anaerobic metabolism appears then to be higbly relevant to performance.

Between 21 and 34 years of age, aging alters the catecholamine responses to supramaximal exercise in endurance trained athletes.

The purpose of this study was to determine the effect of aging and training on the adrenaline (A) and noradrenaline (NA) responses during the Wingate-test in three age groups of subjects: 21 year old untrained subjects (21U), 21 year old endurance trained (21T) (national elite runners), 34 year old endurance trained (34T) (national elite runners). Performances during the test were judged using the usual parameters of peak power (Wmax) and mean power (W) expressed in absolute or relative values. A and NA responses were measured at rest (A0 and NA0) immediately at the end of the exercise (Amax and NAmax) and after 5 minutes recovery (A5 and NA5). Plasma maximal lactate (La(max)) was determined 3 minutes after the end of the exercise. Wmax, W and La(max) were always significantly lower in 34T compared to 21T and 21U. The catecholamine responses were similar in 21T and 21U. Inversely, a significantly lower value of Amax was observed in 34T (2.01 +/- 0.5 nmol x l(-1)) compared to 21U (3.62 +/- 0.3 nmol x l(-1)) associated with a significantly higher value of NA(max) in 34T versus 21T and 21U. Thus, the Amax/NA(max) ratio was found to be significantly lower in the older subjects versus both 21T and 21U. All these findings indicated that endurance training did not affect the sympathoadrenergic responses to a supramaximal exercise and suggested that only one decade may reduce the capacity of the medulla to secrete adrenaline and therefore the adrenal medulla responsiveness to the sympathetic nervous activity.

Adrenal medulla responsiveness to the sympathetic nervous activity in sprinters and untrained subjects during a supramaximal exercise.

The purpose of this study was to compare the adrenal medullar responsiveness to the sympathetic nervous activity between sprinters and untrained subjects after a supramaximal exercise (Wingate-test). Thirteen subjects took part in this study: 7 male athletes (20.3+/-1.8 years) competing in sprint running (S) and 6 untrained men (UT) (21+/-1.3 years). They performed an incremental treadmill test to determine the maximal oxygen uptake (VO2max), a force-velocity test and a Wingate-test on 3 different days, separated by a maximal interval of 15 days. The maximal power (Wmax) and the mean power (W) were determined from the Wingate-test on a cycle ergometer. Plasma lactate, adrenaline and noradrenaline concentrations were determined at rest (La0, A0, NA0), immediately after the Wingate-test (Amax, NAmax) and after 5 minutes recovery (Lamax, A5 and NA5). S exhibited higher performances than UT during the Wingate-test as shown by their significantly higher values of Wmax (1111+/-38 w in S vs 886+/-148 w in UT), W (822+/-37 w in S vs 646+/-69 w in UT) and Lamax (16.8+/1.8 mmol x l(-1) in S vs 12.2+/-2.5 mmol x l(-1) in UT). At the end of the test the NAmax values were similar in both groups whereas the Amax were significantly higher in S (7.6 +/- 1.4 nmol x l(-1) in S vs 3.6 +/- 3.2 nmol x l(-1) in UT). This leads to a higher Amax/NAmax ratio for sprinters compared to untrained subjects (0.7+/-0.2 in S vs 0.3+/-0.2 in UT, p < 0.05). As the disappearance of A (estimated by the Amax-A5 difference) was not lower in S (6.4+/1.5 nmol x l(-1) in S vs 1.8+/-4 nmol x l(-1) in UT), the higher Amax values in S might be explained by a greater secretion level of A. Conversely the identical NAmax values in both groups suggested that this kind of exercise induced the same sympathetic input in S and UT. Consequently the higher Amax/NAmax ratio in S argued in favor of a higher responsiveness of the adrenal medulla of sprinters to the same sympathetic input.