Aim: This study was designed to examine the effect of training on components of the metabolic sy... more 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 VO2peak 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.
ABSTRACT Introduction The aim of the study was to compare two relay modalities used in cyclist te... more ABSTRACT Introduction The aim of the study was to compare two relay modalities used in cyclist team time trial (TTT) in term of performance, physiological responses and perceived exertion. Facts A better performance was realized with the one-line-relay-modality compared to the double-line-relay-modality (42.0 vs. 40.5 km/h). The power output (78.5 ± 2.2 vs. 74.5 ± 2.5% MAP) as well as the HR (88.5 ± 2.2 vs. 86.0 ± 1.9% maxHR) average values were significantly higher for TTT-one-line-relay than for TTT-double-line-relay (P &lt; 0.05). The TTT-one-line-relay has been perceived as more difficult (P &lt; 0.05). Conclusion In terms of performance the TTT-one-line-relay is more efficient but also more difficult than the TTT-double-line-relay. Thus, these two approaches are interesting in competing but need feed different ambitions.
Several methods have tried to quantify physical activity using the relation between heart rate (H... more Several methods have tried to quantify physical activity using the relation between heart rate (HR) and oxygen consumption ( \( \dot V \) O2). Considering the limits of this relation, we focus our work on another physiological index: ventilation ( \( \dot V \) E). The aim of this study is to show that \( \dot V \) E is more strongly correlated with \( \dot V \) O2 than HR. Eight male subjects carried out four physical activities of various intensities: walking at 4 km.h-1, walking at 4 km.h-1 with load, running at 8 km.h-1 and cycling at 60 W. The ventilatory parameters ( \( \dot V \) O2 and \( \dot V \) E) were measured by a portable indirect calorimetry system (VO2000 MedGraphics) and HR was measured with a cardiofrequencemeter. Coefficients of determination (r2 linear) of the relations \( \dot V \) O2= f ( \( \dot V \) E) and \( \dot V \) O2= f (HR) were calculated for each subject (on each activity [r2 Ttot: 64 regressions], on all the four activities [r2 4activities: 16 regressions]) and then for the eight subjects joined together on all the four activities (r2 global: 2 regressions). Results showed that the r2 Ttot of the relation \( \dot V \) O2= f ( \( \dot V \) E) were significantly higher than those of the relation \( \dot V \) O2= f (HR) for the tasks: walking at 4 km.h-1 (p-1 with load (p-1 (p2 4activity of the relation \( \dot V \) O2= f ( \( \dot V \) E) were significantly higher than those of the relation \( \dot V \) O2 = f (HR) (p≤0.001). Finally, the r2 global of the relation \( \dot V \) O2= f ( \( \dot V \) E) were higher than those of the relation \( \dot V \) O2 = f (HR). In view of these results, it seems that \( \dot V \) E is more strongly correlated with \( \dot V \) O2 than HR. This approach seems very promising in order to develop a new method for the quantification of physical activity. Nevertheless, other experiments with a more significant number of subjects and activities have to be carried out to validate this first study.
Applied Physiology Nutrition and Metabolism-physiologie Appliquee Nutrition Et Metabolisme, 2003
We tested seven physical education students whether 30-s sprint anaerobic exercise (Wingate test)... more We tested seven physical education students whether 30-s sprint anaerobic exercise (Wingate test) would result in oxidative stress (evaluated by lipid radical levels) sufficient to alter plasma non-enzymatic antioxidant status (plasma uric acid, ascorbic acid, alpha-tocopherol, beta-carotene). This study demonstrates that 1) Wingate test increases plasma uric and ascorbic acid concentrations (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05), and decreases plasma alpha-tocopherol and beta-carotene levels (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05); 2) lipid radical levels at rest and sprint performance are negatively correlated with resting plasma uric acid and alpha-tocopherol concentrations (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05). In conclusion, this study 1) demonstrates that a 30-s sprint anaerobic exercise is associated with acute changes in plasma non-enzymatic antioxidant status, 2) indicates that the subjects with largest leg peak power are those who exhibit the lowest plasma antioxidant status at rest (uric acid and alpha-tocopherol), 3) and suggests that antioxidant intake by maintaining plasma antioxidant concentration at rest in the normal range might protect athletes against oxidative stress induced by exercise.
The purpose of our study was to compare time to exhaustion (t lim) and time spent at a high level... more The purpose of our study was to compare time to exhaustion (t lim) and time spent at a high level of oxygen uptake (V̇O2) during two high-intensity short intermittent exercises (30 s-30 s) realized with or without series. Eleven young endurance-trained athletes [16.6 (0.4) years] took part in three field tests until exhaustion: (1) a maximal graded test to measure their maximal aerobic velocity (MAV) and maximal oxygen uptake (V̇O2max); (2) and (3) two randomized intermittent exercises (30 s at 110% of MAV alternated with 30 s at 50% of MAV): one alternating repetitions non-stop (IE) and another including 4 min recovery every six repetitions (IEs). The mean t lim measured during IEs was significantly longer than IE [respectively 960.0 (102.0) s vs 621.8 (56.2) s]. The time spent at V̇O2max(t V̇O2max) and the time spent above 90% of V̇O2max(t 90%V̇O2max) did not differ significantly according to the type of exercise: with or without series [respectively t V̇O2max was 158.2 (59.7) s vs 178.0 (56.5) s and t 90%V̇O2max was 290.4 (84.3) s vs 345.0 (61.6) s] but when expressed as a relative value, t 90%V̇O2max during IEs was significantly lower than during IE [respectively 36.4 (10.4)% t lim vs 58.3 (8.7)% t lim]. Despite a significant decrease (P V̇O2max at the start of each series during IEs [respectively 165.0 (43.1) s for the first series and 82.5 (15.8) s for the second series (n=6)] the time spent under 90% of V̇O2max limited the t 90%V̇O2max during each series. In conclusion, our results showed that intermittent exercise with series does not permit an increase in the time spent at a high level of V̇O2; however, the athletes performed more repetitions of short intense exercise.
IntroductionThe purpose of this study was to evaluate the effect of sprint training on plasma cat... more IntroductionThe purpose of this study was to evaluate the effect of sprint training on plasma catecholamine concentrations in response to a-6 second-sprint exercise in adolescent boys (GE). Moreover, to judge of the respective effects of training and pubertal maturation, we proposed the same protocol to a control group of adolescents (GT).
The present study was designed to examine the possible changes in body composition, insulin-like ... more The present study was designed to examine the possible changes in body composition, insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein-3 (IGFBP-3) and inflammatory markers of obese children in response to a 2-month program of exercise training combined with dietary restriction. Twenty-eight obese children (age 13.2 +/- 0.7 years, body mass index 30.9 +/- 1.3) were randomly assigned to a diet/training group or a control group and were tested two times: once before and once at the end of the experimental period. They performed a progressive cycle ergometer test at each visit. Substrate oxidation was evaluated by indirect calorimetry. Training was individualized at the point when fat oxidation was maximal (Lipox(max)). Diet/training induced a significant decrease in body weight and body fat (after vs. before, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Plasma concentrations of IGF-1, IGFBP-3 and inflammatory markers were significantly decreased after the completion of the program. The diet/training program resulted in an increase in VO(2max)ACSM (24.6 +/- 2.5 to 33.1 +/- 3.1 ml/min/kg, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) at the end of the intervention period. These data suggest that in the presence of weight loss, exercise training improves inflammatory markers and IGF-1 and IGFBP-3 levels in obese children.
To examine if, in young obese patients, an individualized training programme in association with ... more 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. 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. The diet/training programme induced both a shift to a higher-power intensity of Lipox(max) (+27.8 + or - 5.1 W; p&lt;0.01) and an increase of lipid oxidation at Lipox(max) (+96.8 + or - 16.2mg/min; p&lt;0.01). The enhancement in lipid oxidation was significantly (p&lt;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). 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.
AimTo determine the effect of a preexercise hyperventilation (HV) on performance measured during ... more AimTo determine the effect of a preexercise hyperventilation (HV) on performance measured during the Wingate test.
In this study we investigated whether plasma catecholamine responses to the Wingate test are affe... more In this study we investigated whether plasma catecholamine responses to the Wingate test are affected by the intensity of training in endurance-trained subjects. To do this we compared plasma adrenaline (A) and noradrenaline (NA) concentrations in response to a Wingate test in three different groups: specialist middle-distance runners (MDR) in 800-m and 1,500-m races, specialist long-distance runners (LDR) 5,000-m and 10,000-m races, and untrained subjects (UT). The maximal power (W max) and the mean power (W) were determined from the Wingate test. Blood lactate (La), plasma A and NA concentrations were analysed at rest (La0, A0 and NA0), immediately at the end of the exercise (Amax and NAmax) and after 5 min recovery (Lamax, A5 and NA5). The ratio Amax/NAmax was considered as an index of the adrenal medulla responsiveness to the sympathetic nervous activity. At the end of the test, W max and W were similar in the three groups but Lamax was significantly greater in MDR compared to LDR and UT [15.2 (2.2) mmol l−1, 11.7 (3.1) mmol l−1, 11.6 (1.6) mmol l−1, respectively, for MDR, LDR and UT; mean (SD)]. Concerning the plasma catecholamine concentrations in response to exercise, MDR and LDR Amax values [3.73 (1.53) nmol l−1, 3.47 (0.74) nmol l−1, respectively, for MDR and LDR] were significantly greater than those of UT [1.48 (0.32) nmol l−1] who also exhibited the lowest NAmax values [11.09 (6.58) nmol l−1] compared to MDR and LDR [20.43 (3.51) nmol l−1; 15.85 (4.88) nmol l−1, respectively, for MDR and LDR]. However, no significant differences were observed between the two trained groups either for Amax or NAmax. These results suggest that long-term endurance training can enhance plasma catecholamine concentrations in response to supramaximal exercise. However, as there were no significant differences between MDR and LDR Amax and NAmax values, the effect of the intensity of training remains to be clarified.
Aim: This study was designed to examine the effect of training on components of the metabolic sy... more 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 VO2peak 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.
ABSTRACT Introduction The aim of the study was to compare two relay modalities used in cyclist te... more ABSTRACT Introduction The aim of the study was to compare two relay modalities used in cyclist team time trial (TTT) in term of performance, physiological responses and perceived exertion. Facts A better performance was realized with the one-line-relay-modality compared to the double-line-relay-modality (42.0 vs. 40.5 km/h). The power output (78.5 ± 2.2 vs. 74.5 ± 2.5% MAP) as well as the HR (88.5 ± 2.2 vs. 86.0 ± 1.9% maxHR) average values were significantly higher for TTT-one-line-relay than for TTT-double-line-relay (P &lt; 0.05). The TTT-one-line-relay has been perceived as more difficult (P &lt; 0.05). Conclusion In terms of performance the TTT-one-line-relay is more efficient but also more difficult than the TTT-double-line-relay. Thus, these two approaches are interesting in competing but need feed different ambitions.
Several methods have tried to quantify physical activity using the relation between heart rate (H... more Several methods have tried to quantify physical activity using the relation between heart rate (HR) and oxygen consumption ( \( \dot V \) O2). Considering the limits of this relation, we focus our work on another physiological index: ventilation ( \( \dot V \) E). The aim of this study is to show that \( \dot V \) E is more strongly correlated with \( \dot V \) O2 than HR. Eight male subjects carried out four physical activities of various intensities: walking at 4 km.h-1, walking at 4 km.h-1 with load, running at 8 km.h-1 and cycling at 60 W. The ventilatory parameters ( \( \dot V \) O2 and \( \dot V \) E) were measured by a portable indirect calorimetry system (VO2000 MedGraphics) and HR was measured with a cardiofrequencemeter. Coefficients of determination (r2 linear) of the relations \( \dot V \) O2= f ( \( \dot V \) E) and \( \dot V \) O2= f (HR) were calculated for each subject (on each activity [r2 Ttot: 64 regressions], on all the four activities [r2 4activities: 16 regressions]) and then for the eight subjects joined together on all the four activities (r2 global: 2 regressions). Results showed that the r2 Ttot of the relation \( \dot V \) O2= f ( \( \dot V \) E) were significantly higher than those of the relation \( \dot V \) O2= f (HR) for the tasks: walking at 4 km.h-1 (p-1 with load (p-1 (p2 4activity of the relation \( \dot V \) O2= f ( \( \dot V \) E) were significantly higher than those of the relation \( \dot V \) O2 = f (HR) (p≤0.001). Finally, the r2 global of the relation \( \dot V \) O2= f ( \( \dot V \) E) were higher than those of the relation \( \dot V \) O2 = f (HR). In view of these results, it seems that \( \dot V \) E is more strongly correlated with \( \dot V \) O2 than HR. This approach seems very promising in order to develop a new method for the quantification of physical activity. Nevertheless, other experiments with a more significant number of subjects and activities have to be carried out to validate this first study.
Applied Physiology Nutrition and Metabolism-physiologie Appliquee Nutrition Et Metabolisme, 2003
We tested seven physical education students whether 30-s sprint anaerobic exercise (Wingate test)... more We tested seven physical education students whether 30-s sprint anaerobic exercise (Wingate test) would result in oxidative stress (evaluated by lipid radical levels) sufficient to alter plasma non-enzymatic antioxidant status (plasma uric acid, ascorbic acid, alpha-tocopherol, beta-carotene). This study demonstrates that 1) Wingate test increases plasma uric and ascorbic acid concentrations (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05), and decreases plasma alpha-tocopherol and beta-carotene levels (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05); 2) lipid radical levels at rest and sprint performance are negatively correlated with resting plasma uric acid and alpha-tocopherol concentrations (p &amp;amp;amp;amp;amp;amp;amp;amp;lt;.05). In conclusion, this study 1) demonstrates that a 30-s sprint anaerobic exercise is associated with acute changes in plasma non-enzymatic antioxidant status, 2) indicates that the subjects with largest leg peak power are those who exhibit the lowest plasma antioxidant status at rest (uric acid and alpha-tocopherol), 3) and suggests that antioxidant intake by maintaining plasma antioxidant concentration at rest in the normal range might protect athletes against oxidative stress induced by exercise.
The purpose of our study was to compare time to exhaustion (t lim) and time spent at a high level... more The purpose of our study was to compare time to exhaustion (t lim) and time spent at a high level of oxygen uptake (V̇O2) during two high-intensity short intermittent exercises (30 s-30 s) realized with or without series. Eleven young endurance-trained athletes [16.6 (0.4) years] took part in three field tests until exhaustion: (1) a maximal graded test to measure their maximal aerobic velocity (MAV) and maximal oxygen uptake (V̇O2max); (2) and (3) two randomized intermittent exercises (30 s at 110% of MAV alternated with 30 s at 50% of MAV): one alternating repetitions non-stop (IE) and another including 4 min recovery every six repetitions (IEs). The mean t lim measured during IEs was significantly longer than IE [respectively 960.0 (102.0) s vs 621.8 (56.2) s]. The time spent at V̇O2max(t V̇O2max) and the time spent above 90% of V̇O2max(t 90%V̇O2max) did not differ significantly according to the type of exercise: with or without series [respectively t V̇O2max was 158.2 (59.7) s vs 178.0 (56.5) s and t 90%V̇O2max was 290.4 (84.3) s vs 345.0 (61.6) s] but when expressed as a relative value, t 90%V̇O2max during IEs was significantly lower than during IE [respectively 36.4 (10.4)% t lim vs 58.3 (8.7)% t lim]. Despite a significant decrease (P V̇O2max at the start of each series during IEs [respectively 165.0 (43.1) s for the first series and 82.5 (15.8) s for the second series (n=6)] the time spent under 90% of V̇O2max limited the t 90%V̇O2max during each series. In conclusion, our results showed that intermittent exercise with series does not permit an increase in the time spent at a high level of V̇O2; however, the athletes performed more repetitions of short intense exercise.
IntroductionThe purpose of this study was to evaluate the effect of sprint training on plasma cat... more IntroductionThe purpose of this study was to evaluate the effect of sprint training on plasma catecholamine concentrations in response to a-6 second-sprint exercise in adolescent boys (GE). Moreover, to judge of the respective effects of training and pubertal maturation, we proposed the same protocol to a control group of adolescents (GT).
The present study was designed to examine the possible changes in body composition, insulin-like ... more The present study was designed to examine the possible changes in body composition, insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein-3 (IGFBP-3) and inflammatory markers of obese children in response to a 2-month program of exercise training combined with dietary restriction. Twenty-eight obese children (age 13.2 +/- 0.7 years, body mass index 30.9 +/- 1.3) were randomly assigned to a diet/training group or a control group and were tested two times: once before and once at the end of the experimental period. They performed a progressive cycle ergometer test at each visit. Substrate oxidation was evaluated by indirect calorimetry. Training was individualized at the point when fat oxidation was maximal (Lipox(max)). Diet/training induced a significant decrease in body weight and body fat (after vs. before, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Plasma concentrations of IGF-1, IGFBP-3 and inflammatory markers were significantly decreased after the completion of the program. The diet/training program resulted in an increase in VO(2max)ACSM (24.6 +/- 2.5 to 33.1 +/- 3.1 ml/min/kg, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) at the end of the intervention period. These data suggest that in the presence of weight loss, exercise training improves inflammatory markers and IGF-1 and IGFBP-3 levels in obese children.
To examine if, in young obese patients, an individualized training programme in association with ... more 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. 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. The diet/training programme induced both a shift to a higher-power intensity of Lipox(max) (+27.8 + or - 5.1 W; p&lt;0.01) and an increase of lipid oxidation at Lipox(max) (+96.8 + or - 16.2mg/min; p&lt;0.01). The enhancement in lipid oxidation was significantly (p&lt;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). 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.
AimTo determine the effect of a preexercise hyperventilation (HV) on performance measured during ... more AimTo determine the effect of a preexercise hyperventilation (HV) on performance measured during the Wingate test.
In this study we investigated whether plasma catecholamine responses to the Wingate test are affe... more In this study we investigated whether plasma catecholamine responses to the Wingate test are affected by the intensity of training in endurance-trained subjects. To do this we compared plasma adrenaline (A) and noradrenaline (NA) concentrations in response to a Wingate test in three different groups: specialist middle-distance runners (MDR) in 800-m and 1,500-m races, specialist long-distance runners (LDR) 5,000-m and 10,000-m races, and untrained subjects (UT). The maximal power (W max) and the mean power (W) were determined from the Wingate test. Blood lactate (La), plasma A and NA concentrations were analysed at rest (La0, A0 and NA0), immediately at the end of the exercise (Amax and NAmax) and after 5 min recovery (Lamax, A5 and NA5). The ratio Amax/NAmax was considered as an index of the adrenal medulla responsiveness to the sympathetic nervous activity. At the end of the test, W max and W were similar in the three groups but Lamax was significantly greater in MDR compared to LDR and UT [15.2 (2.2) mmol l−1, 11.7 (3.1) mmol l−1, 11.6 (1.6) mmol l−1, respectively, for MDR, LDR and UT; mean (SD)]. Concerning the plasma catecholamine concentrations in response to exercise, MDR and LDR Amax values [3.73 (1.53) nmol l−1, 3.47 (0.74) nmol l−1, respectively, for MDR and LDR] were significantly greater than those of UT [1.48 (0.32) nmol l−1] who also exhibited the lowest NAmax values [11.09 (6.58) nmol l−1] compared to MDR and LDR [20.43 (3.51) nmol l−1; 15.85 (4.88) nmol l−1, respectively, for MDR and LDR]. However, no significant differences were observed between the two trained groups either for Amax or NAmax. These results suggest that long-term endurance training can enhance plasma catecholamine concentrations in response to supramaximal exercise. However, as there were no significant differences between MDR and LDR Amax and NAmax values, the effect of the intensity of training remains to be clarified.
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