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1.
J Appl Physiol (1985) ; 95(2): 685-91, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12433857

ABSTRACT

In a cross-sectional study, central and peripheral arteries were investigated noninvasively in high-performance athletes and in untrained subjects. The diastolic inner vessel diameter (D) of the thoracic and abdominal aorta, the subclavian artery (Sub), and common femoral artery (Fem) were determined by duplex sonography in 18 able-bodied professional tennis players, 34 able-bodied elite road cyclist athletes, 26 athletes with paraplegia, 17 below-knee amputated athletes, and 30 able-bodied, untrained subjects. The vessel cross-sectional areas (CSA) were set in relation to body surface area (BSA), and the cross-section index (CS-index = CSA/BSA) was calculated. Volumetric blood flow was determined in Sub and Fem via a pulsed-wave Doppler system and was set in relation to heart rate to calculate the stroke flow. A significantly increased D of Sub was found in the racket arm of able-bodied tennis players compared with the opposite arm (19%). Fem of able-bodied road cyclist athletes and of the intact limb in below-knee amputated athletes showed similar increases. D of Fem was lower in athletes with paraplegia (37%) and in below-knee amputated athletes proximal to the lesion (21%) compared with able-bodied, untrained subjects; CS-indexes were reduced 57 and 31%, respectively. Athletes with paraplegia demonstrated a larger D (19%) and a larger CS-index in Sub (54%) than able-bodied, untrained subjects. No significant differences in D and CS-indexes of the thoracic and abdominal aorta were found between any of the groups. The changes measured in Sub and Fem were associated with corresponding alterations in blood flow and stroke flow in all groups. The study suggests that the size and blood flow volume of the proximal limb arteries are adjusted to the metabolic needs of the corresponding extremity musculature and underscore the impact of exercise training or disuse on the structure and the function of the arterial system.


Subject(s)
Arteries/diagnostic imaging , Arteries/physiopathology , Bicycling , Disabled Persons , Physical Education and Training , Tennis , Adult , Amputees , Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/physiopathology , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/physiopathology , Case-Control Studies , Cross-Sectional Studies , Extremities/blood supply , Femoral Artery/diagnostic imaging , Femoral Artery/physiopathology , Humans , Leg , Paraplegia/physiopathology , Regional Blood Flow , Stroke Volume , Subclavian Artery/diagnostic imaging , Subclavian Artery/physiopathology , Ultrasonography, Doppler, Duplex
2.
Z Gerontol Geriatr ; 35(2): 151-6, 2002 Apr.
Article in German | MEDLINE | ID: mdl-12080578

ABSTRACT

Age-related morphological changes in the cardiovascular system refer to a thickening of the arterial wall as well as a diffuse increase in the wall thickness of the myocardium. In terms of function, this leads to a decrease of the myocardial contractility in systole and to a delay of the diastolic myocardial relaxation. At the arterial wall, an impairment of wall elasticity as well as a decrease of the vasoreagibility can be observed. The systolic blood pressure and the blood pressure amplitude rise; the blood flow-dependent vasodilatation mediated by endothelial cells decreases. The loss of cardiac pacemaker cells by approximately 90% from the 2nd to the 8th decade leads to a reduction of the heart rate variability and to a decrease of the maximum heart rate during exhaustive physical exercise. Hemodynamically these changes resulted in a continuous decline of the maximum cardiac output as well as the maximum oxygen transport capacity. Between the 3rd and 8th decade the peripheral skeletal muscle mass decreases as a result of a reduction of the size and the number of muscle fibers with an overproportional loss of 30-40% regarding the highly glycolytic type IIb fibers. Furthermore, the intramuscular capillarization declines so that, with a concomitant decrease in the number and size of the mitochondria, the supply with oxygen and energy sources and consecutively the aerobic muscular energy metabolism decreases by 8-10% per decade beginning with the 4th to 5th decade. Additionally, the maximum and explosive muscular strength decreases by 30-35% from the 4th decade onwards. In older, healthy men who perform a regular aerobic muscular training in endurance sport disciplines (e.g., walking, jogging or cycling), a decrease of the resting heart rate, a restoration of the primarily lowered heart rate variability, an improvement of the early diastolic left-ventricular filling as well as a significant increase in the VO2max could be proven. Other studies showed that regular endurance training on a cycle-ergometer resulted in a significant increase in capillarization within the exercising muscle groups. In older, trained individuals a reduced stiffness of the arterial vessel walls and an improved maximum exercise-induced muscular blood supply occurs. In other training studies performed with older subjects, a positive influence of regular endurance training on the carbohydrate metabolism along with an improvement of the primarily reduced insulin sensitivity could be demonstrated. In older men and women who regularly underwent muscular strength training, a significant increase in maximum strength with a significant increase in the proportion of type II muscle fibers was found.


Subject(s)
Cardiac Rehabilitation , Exercise/physiology , Hemodynamics/physiology , Muscle Weakness/rehabilitation , Muscle, Skeletal/physiopathology , Physical Fitness/physiology , Adult , Aged , Aged, 80 and over , Cardiovascular Diseases/physiopathology , Female , Humans , Male , Middle Aged , Muscle Weakness/physiopathology
3.
J Sports Med Phys Fitness ; 41(2): 139-46, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11447353

ABSTRACT

BACKGROUND: Retrospective analysis of peak performances can be a usefull tool for the estimation of future trends in high performance sports. The purpose of this study was to investigate the evolution of performance in track cycling from 1979 to 1999 and to asses age- and gender-related differences. METHODS: We studied the results of the world track cycling championships for this period in 200 m, 1000 m, individual and team pursuit races for elite and junior athletes. Overall trends, performance differences between rank 1 and 5, gender- and age-related differences were calculated. RESULTS: They show a significant (p<0.01) improvement in 1000 m, individual and team pursuit times for men and individual pursuit times for women. No significant evolution was seen in 200 m performance. In junior riders, only male athletes showed a continuous, significant improvement of average race speed in individual and team pursuit over the study period. Gender difference was 11+/-1.8% in all disciplines at all ages. Difference between elite and junior riders ranged between 5+/-2.1% for male and 6.1+/-2.2% for female athletes. The gap between rank 1 and 5 remained constant (2-3%) over the study period. CONCLUSIONS: A continuous improvement of performance over the last 20 years is visible in track cycling endurance disciplines. New technical developments show no statistical significant impact. The performance gap between male and female athletes is constant, independent of discipline or race distance and comparable to observations in other sports. Age-related differences in performance is most visible in disciplines requiring short, high intensity power output. Based on these data, estimation of possible winning times and adaptation of training programs for future track cycling competitions might be facilitated.


Subject(s)
Bicycling/physiology , Physical Fitness/physiology , Adolescent , Adult , Age Factors , Female , Humans , Linear Models , Male , Retrospective Studies , Sex Factors
4.
J Sports Med Phys Fitness ; 41(2): 269-74, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11447373

ABSTRACT

BACKGROUND: The purpose of the study was to specify and define the differences of psychophysical stress in elite tennis players under practice and tournament conditions. METHODS: Basal, pre- and postcompetition urine samples of 26 nationally ranked players (NR) were analysed for concentrations of epinephrine (EPI) and norepinephrine (NE) under practice (P) and tournament conditions (T). Results were completed by the values obtained from two internationally ranked players (IR) competing in 6 (player A) and 5 (player B) Davis-Cup matches, respectively. RESULTS: In NR, pre- and postcompetition concentrations for EPI were significantly higher under tournament conditions (T: 1.33+/-0.65 and 3.66+/-2.51 microg/100 mg creatinine vs P: 0.61+/-0.39 and 0.97+/-0.59 microg/100 mg creatinine). The NE/EPI ratio showed significantly inverse results (T: 3.53+/-1.87 and 3.58+/-1.59 vs P: 8.08+/-6.99 and 10.03+/-6.58), whereas the concentration of NE did not differ between the two conditions. Significant correlations were found between the level of perceived nervousness (ten-point-likert scale) and the postcompetition concentration of EPI (r=0.491, p<0.05) and the NE/EPI ratio (r=-0.595, p<0.01). Players who felt affected by nervousness in their performance outcome showed significantly lower NE/EPI ratios (2.73+/-1.44 vs 4.49+/-2.54, p<0.05). The Davis-Cup-Players showed intra-individually constant but inter-individually different concentrations of EPI (A= 2.2+/-0.5 vs B= 7.0+/-0.8 microg/100 mg creatinine), NE (A= 7.4+/-2.2 vs B= 15.5+/-3.2 microg/100 mg creatinine) and the ratio of NE/EPI (A= 3.7+/-2.2 vs B= 2.2+/-0.7). CONCLUSIONS: In tennis tournaments, sympathetic activity is increased due to a higher psychological stress which may impair performance. Practical efforts should focus on psycho-regulative methods and psychophysical regeneration for players dealing with a chronic sympathetic hyper-activation.


Subject(s)
Epinephrine/urine , Norepinephrine/urine , Stress, Psychological/urine , Tennis/psychology , Adult , Analysis of Variance , Biomarkers/urine , Humans , Male , Psychophysiology , Stress, Psychological/physiopathology , Stress, Psychological/psychology
6.
Circulation ; 103(15): 1942-8, 2001 Apr 17.
Article in English | MEDLINE | ID: mdl-11306521

ABSTRACT

BACKGROUND: Although HMG-CoA reductase inhibitors (HMGRIs) are effective lipid-lowering agents, it remains controversial whether these agents also lower dense LDL (dLDL), a predominance of which is considered to contribute to the atherogenicity of the metabolic syndrome. METHODS AND RESULTS: In a multicenter, double-blind, randomized, placebo-controlled study, we determined the effect of the HMGRI fluvastatin on lipids, apolipoproteins, and LDL subfractions (by equilibrium density gradient ultracentrifugation). A total of 52 postmenopausal women with combined hyperlipidemia and increased dLDL were treated with either fluvastatin 40 mg/d (n=35) or placebo (n=17). After 12 weeks' treatment, significant reductions (P<0.001) in total cholesterol (-19%), IDL cholesterol (-35%), LDL cholesterol (-23%), apolipoprotein B (-21%), and apolipoprotein B in dLDL (-42%) were apparent among fluvastatin recipients. No significant changes in triglycerides or HDL cholesterol were observed. The effect of fluvastatin on dLDL was correlated with baseline values. There was no consistent relationship, however, between the effect of fluvastatin on triglycerides and the decrease in dLDL. CONCLUSIONS: Fluvastatin lowers total and LDL cholesterol and the concentration of dLDL. This profile may contribute to an antiatherogenic effect for fluvastatin that is greater than expected on the basis of changes in lipids and apolipoproteins.


Subject(s)
Anticholesteremic Agents/administration & dosage , Fatty Acids, Monounsaturated/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hyperlipidemias/drug therapy , Indoles/administration & dosage , Lipoproteins, LDL/blood , Apolipoproteins B/blood , Cholesterol/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Double-Blind Method , Female , Fluvastatin , Humans , Hyperlipidemias/blood , Lipoproteins/blood , Phenotype , Postmenopause , Treatment Outcome , Triglycerides/blood
7.
Med Sci Sports Exerc ; 33(4): 654-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11283444

ABSTRACT

During the past decade, the physical and mental stress in professional tennis has been constantly increasing. The overall intensity in tennis ranges between 60 and 70% of maximum oxygen uptake and the energy requirements are mainly provided by aerobic energy metabolism. Therefore, particularly with respect to the duration of the tournaments and the length of the matches, a good aerobic capacity promotes continuous success in professional tennis. During frequent periods of high intensity, however, muscular energy is derived from anaerobic glycolysis. Therefore, sports-specific conditioning programs in tennis should improve both glycolytic and oxidative muscular metabolism. Years of training and competition induce a number of cardiovascular and metabolic adaptations: an increase in heart size in terms of an athlete's heart, higher oxygen uptake capacity, improved muscular oxidative enzyme activities, reduced baseline catecholamine levels, and a lower resting heart rate. In addition, tennis induces side-specific increments in bone density, bone diameter, and bone length of the upper extremity. Furthermore, structural and functional adaptations of the conducting arteries in the preferred arm could be demonstrated in professional tennis players. In conclusion, tennis is a very complex sport involving strength, power, speed, agility and explosiveness, as well as endurance components. Scientific data on exercise-related cardiovascular and metabolic parameters in professional tennis are important to evaluate the players individual fitness level and will help to improve sports-specific conditioning programs. This in turn will not only enhance performance but also prevent overstrain and burnout syndromes.


Subject(s)
Adaptation, Physiological , Cardiovascular Physiological Phenomena , Energy Metabolism/physiology , Hormones/metabolism , Tennis/physiology , Humans , Water-Electrolyte Balance/physiology
8.
Int J Sports Med ; 22(1): 2-7, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11258636

ABSTRACT

Autonomic dysreflexia presents a special situation in high-lesion spinal cord injury, however, intentionally or self-induced autonomic dysreflexia directly before or during competition to increase performance, so called 'boosting', is also being reported. In order to examine the influence of autonomic dysreflexia on plasma catecholamines, cardiocirculatory and metabolic parameters, 6 spinal cord injured wheelchair athletes with high-level lesions underwent wheelchair ergometry without (ST1) and with (ST2) autonomic dysreflexia. At the point of exhaustion significantly higher values for norepinephrine and epinephrine were observed in ST2 than in ST1. During autonomic dysreflexia a significantly higher peak performance (77.5 vs. 72.5 watt), higher peak heart rate (161 vs. 149 x min(-1)), and peak oxygen consumption (1.96 vs. 1.85 l x min(-1)), with comparable peak lactate (7.11 vs. 7.00 mmol x l(-1)) were reached on average. The blood pressure values in ST2 were partially hypertensive and higher than in ST1. In conclusion, autonomic dysreflexia, as a sympathetic spinal reflex, leads to a higher release of catecholamines during exercise. This results in higher peak performance, peak heart rate, peak oxygen consumption, and higher blood pressure values. The peak lactate, as an indicator of the anaerobic lactate metabolism, was unchanged. However, autonomic dysreflexia presents an unpredictable risk, caused predominantly by hypertensive blood pressure values, for high-lesion spinal cord injured persons at rest and more so during exercise; it is seen as a prohibited manipulation by the doping guidelines of the International Paralympic Committee.


Subject(s)
Autonomic Dysreflexia/physiopathology , Catecholamines/blood , Exercise/physiology , Spinal Cord Injuries/complications , Wheelchairs , Adult , Disabled Persons , Heart Rate , Humans , Hypertension , Lactic Acid/blood , Male , Oxygen Consumption
9.
Med Sci Sports Exerc ; 33(2): 189-95, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11224804

ABSTRACT

PURPOSE: The purpose of this study was to assess left ventricular (LV) wall motion in highly endurance-trained athletes to evaluate LV diastolic function in physiologically hypertrophied hearts. BACKGROUND: Diastolic filling dynamics have previously been examined in endurance-trained athletes by measuring pulsed-wave mitral inflow velocities during the early and atrial filling phase, indicating an unimpaired LV function. Assessment of LV wall motion may give additional information about the LV diastolic function in endurance-trained athletes. METHODS: Left ventricular mass (LVM) and volume (LVV) were determined by M-mode echocardiography. Peak LV wall motion in the region of the basal septum close to the mitral anulus were measured during the early rapid and atrial filling phase by tissue Doppler in 30 endurance-trained athletes (T) and 16 sedentary control subjects (C) presumed to be healthy. RESULTS: Myocardial LVM and LVV in T (LVM 159.4 +/- 18.0 g.m(-2), LVV 100.4 +/- 13.0 mL.m(-2)) were significantly higher than in C (LVM 105.7 +/- 12.0.m(-2), LVV 70.1 +/- 11.9 mL.m(-2)), and heart rate (HR) was significantly lower (HR C: 69.6 +/- 11.0 bpm, T 50.9 +/- 8.7 bpm),which is consistent with endurance training (P < 0.01 for both). Peak LV wall motion during the early rapid filling phase did not differ significantly between the groups (T: 10.69 +/- 1.46 cm.(s-)1; C: 10.61 +/- 1.52 cm.(s-)1). Peak atrial wall motion was significantly lower in T (4.53 +/- 0.84 cm.s-1) versus C (5.74 +/- 0.75 cm.s(-1)), and the ratio of peak early diastolic to atrial wall motion was consequently higher in athletes (P < 0.01 for both). CONCLUSION: Regional wall motion at the basal septum near the mitral anulus during the early rapid filling phase is not altered by an increase in LVM or LVV when associated with endurance training.


Subject(s)
Physical Endurance , Ventricular Function, Left , Adult , Diastole/physiology , Echocardiography, Doppler, Pulsed , Humans , Male , Myocardium
10.
Z Kardiol ; 90(11): 813-23, 2001 Nov.
Article in German | MEDLINE | ID: mdl-11771449

ABSTRACT

Dynamic muscular exercise performed by healthy subjects leads to a rise in the left ventricular blood ejection with an acute increase in the local wall shear stress on the endothelium of the arterial vessels. These hemodynamic changes results in a release of endothelium-dependent relaxing factors, one of them concerns nitric oxide (NO). Therefore an arterial vasodilatation with an acute increase in the blood flow volume to the exercising muscle groups occurs. If more than 1/6 of the skeletal musculature is involved in exercise and if training duration exceeds 3-5 hours a week the chronically increased blood flow volume in the cardiovascular system triggers structural and functional changes of the heart and the arterial vessels. It develops a functional intact excentric hypertrophy of the myocardium; within the arterial vessels an increase in the diameter of the muscular arteries supplying the trained muscle groups occurs. These training-induced adaptations of the cardiovascular system are adjusted to improve the aerobic skeletal muscle metabolism. In congestive heart failure a pathological excentric myocardial hypertrophy is found. In this case the systolic myocardial function is impaired and the left ventricular ejection fraction is reduced already in early stages, so that the cardiac output can not be sufficiently increased during exercise. In addition a dysfunction of the endothelium of the arterial vessels occurs. As a consequence the endothelium-dependent arterial vasodilation is reduced, so that the peripheral arteries could not supply the muscle groups involved in exercise with enough blood flow volume. Therefore, the acute delivery of the working musculature with oxygen and energy substrates is insufficient, so that premature muscular fatigue occurs. The reduced exercise resistance of the patients leads chronically to a generalized skeletal muscle atrophy. Ultrastructural analysis revealed a decrease of oxidative type 1 muscle fibers with a relative increase of more glycolytic type 2 fibers. In addition, the volume density and the surface area of the cristae of mitochondria are reduced. All these changes results in a decrease of aerobic skeletal muscle metabolism independent of the blood flow volume, so that the physical fitness of the patients progressively decline. On the basis of the training-induced physiological adaptations of the cardiovascular system, a special exercise therapy supervised by a physician was developed for patients with congestive heart failure NYHA II/III. It have been shown that various exercise programs, which are adjusted to the degree of cardiac function impairment are suitable to restore the endothelial dysfunction of the arterial vessels as well as to cure the disturbed skeletal muscle metabolism in these patients independent of an improvement of cardiac function. Therefore in patients with congestive heart failure NYHA II/III who underwent regularly such an exercise therapy, the secondary impaired physical fitness could be rebuild without an excessive risk for an acute exercise-induced cardiovascular emergency.


Subject(s)
Endothelium, Vascular/physiopathology , Exercise/physiology , Heart Failure/rehabilitation , Muscle, Skeletal/physiopathology , Muscle, Smooth, Vascular/physiopathology , Cardiac Output/physiology , Heart Failure/physiopathology , Hemodynamics/physiology , Humans , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Left/rehabilitation
11.
Z Arztl Fortbild Qualitatssich ; 94(8): 677-81, 2000 Sep.
Article in German | MEDLINE | ID: mdl-11084723

ABSTRACT

Freiburg Intervention Trial for Obese Children (FITOC) is an interdisciplinary treatment program for obese children, which is established in Freiburg since 1987. Obese children at the age of 8-11 are treated in an eight months intensive period and a follow-up period of 4 months or more. Since 1990 data from 283 children coming out of 15 treatment groups (about 2 groups per year) were collected and analyzed. The program consists of regular physical training (3 times a week), comprehensive nutrition and behaviour training (overall 7 parents evenings each 4 to 6 weeks and 7 cookery courses for the kids in the same time scale). The parents evenings are filled with theoretical and practical information about nutrition as well as background information about the psychological and physiological problems in obese children. In the first examination and the regular control examinations anthropometric, biochemical and exercise physiology data are investigated. In addition, questionnaires for nutrition and behaviour are analysed on a regular basis. At each examination, depending on the progress in therapy, a new orientation with adapted goals will be discussed with the child and the parents. For the growing children a moderate reduction or long term stabilisation of weight will lead to success. Teaching goal for the children in the intensive period is to control themselves and, depending on their specific situation, to establish individual recommendations on a long term basis. The sports program should lead to an increase in self-esteem and a raise in daily energy expenditure. The team includes a physician, a nutritionist, a psychologist and a sports teacher. From 1997 the program was spread to institutions in the surroundings of Freiburg. Training for the external teams is provided for in continuous seminars. Teaching material includes a manual, forms and transparencies. The major goal is to secure quality by continuous training and close interaction between the institutions. Till now the program is performed by a couple of multiplication groups in different regions of Germany. First data analysis has shown that the out-patient program is transferable and comparable results are reachable after a standardized training course for the included therapists. The plan for 2000 and 2001 is to increase the number of centers involved to a total of 20 all over Germany.


Subject(s)
Exercise , Obesity/rehabilitation , Patient Education as Topic , Behavior Therapy , Child , Cooking , Female , Follow-Up Studies , Germany , Humans , Nutritional Physiological Phenomena , Obesity/diet therapy , Parent-Child Relations , Patient Care Team , Physical Fitness
12.
J Appl Physiol (1985) ; 89(5): 1956-63, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11053349

ABSTRACT

In humans, the relationships of blood flow changes to structure, function, and shear rate of conducting arteries have not been thoroughly examined. Therefore, the purpose of this study was to investigate these parameters of the elastic-type, common carotid artery (CCA) and the muscular-type, common femoral artery (CFA) in long-term highly active and extremely inactive individuals, assuming that the impact of activity-induced blood flow changes on conduit arteries, if any, should be seen in these subjects. We examined 21 highly endurance-trained athletes (A), 10 paraplegic subjects (P), and 20 sedentary subjects (S) by means of noninvasive ultrasound. As a result, the CFA diameter and compliance were highest in A (9.7+/-0.81 mm; 1.84 +/-0.54 mm(2)/kPa) and lowest in P (5.9+/-0.7 mm; 0.54+/-0.27 mm(2)/kPa) compared with S (8.3+/-1.0 mm; 0.92+/-0.48 mm(2)/kPa) with P <0.01 among the groups. Both parameters correlated with each other (r = 0.62; P<0.01). Compared with A (378+/-84 s(-1); 37+/-15 s(-1)) and S (356+/-113 s(-1); 36+/-20 s(-1)), the peak and mean shear rates of the CFA were almost or more than doubled in P (588+/-120 s(-1); 89+/-26 s(-1)). In the CCA, only the compliance and peak shear rate showed significant differences among the groups (A: 1.28+/-0.47 mm(2)/kPa, 660+/-138 s(-1); S: 1.04+/-0.27 mm(2)/kPa, 588+/-109 s(-1); P: 0.65+/- 0.22 mm(2)/kPa, 490+/-149 s(-1); P<0.05). In conclusion, the results suggest a structural and functional adaptation in the CFA and a predominantly functional adaptation of the arterial wall properties to differences in the physical activity level and associated exercise-induced blood flow changes in the CCA. The results for humans confirm those from animal experiments. Similar shear rate values of S and P in the CFA support the hypothesis of constant shear stress regulation due to local blood flow changes in humans. On the other hand, the increased shear rate in the CFA in P indicates an at least partially nonphysiological response of the arterial wall in long-term chronic sympathectomy due to a change in local blood flow.


Subject(s)
Carotid Arteries/physiology , Femoral Artery/physiology , Paraplegia/physiopathology , Physical Endurance/physiology , Adult , Blood Flow Velocity/physiology , Body Mass Index , Diastole/physiology , Humans , Laser-Doppler Flowmetry , Male , Middle Aged , Pulsatile Flow/physiology , Systole/physiology
13.
Med Sci Sports Exerc ; 32(10): 1709-12, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11039642

ABSTRACT

PURPOSE: In a case control study, we examined the allelic frequencies and genotype distributions of two restricted fragment length polymorphisms (RFLP) in the alpha-2A-adrenoceptor gene (ADRA2A) and beta-2-adrenoceptor gene (ADRB2) among elite endurance athletes (EEA) and sedentary controls (SC). METHODS: The EEA group included 148 Caucasian male subjects recruited on the basis that they had a VO2max > 74 mL O2 x kg(-1) x min(-1). The SC group comprised 149 unrelated sedentary male subjects, all Caucasians, from the Quebec Family Study. After digestion with the restriction enzymes Dra I (ADRA2A) and Ban I (ADRB2), Southern blotting and hybridization techniques were used to detect the mutations in the two ADR genes, which are encoded on chromosomes 10 (q24-26) and 5 (q31-32), respectively. RESULTS: For the Dra I ADRA2A RFLP, we observed a significant difference in genotype distributions between the two groups (P = 0.037). A higher frequency of the 6.7-kb allele was observed in the EEA group compared with the SC group (P = 0.013). No statistically significant difference was found between groups for the Ban I ADRB2 polymorphic site. Genotype frequencies for both genes in both groups were in Hardy-Weinberg equilibrium. CONCLUSIONS: In summary, we found evidence that ADRA2A gene variability detected with Dra I is weakly associated with elite endurance athlete status, and we conclude that genetic variation in the ADRA2A gene or a locus in close proximity may play a role in being able to sustain the endurance training regimen necessary to attain a high level of maximal aerobic power.


Subject(s)
Physical Endurance , Polymorphism, Restriction Fragment Length , Receptors, Adrenergic, alpha-2/genetics , Sports , Alleles , Blotting, Southern , Case-Control Studies , Humans , Male , White People/genetics
14.
Int J Sports Med ; 21(5): 380-5, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10950450

ABSTRACT

BACKGROUND: In international cycling and cross-country skiing competitions, blood tests are used to unmask the performance enhancing misuse of erythropoietin. Haematocrit (cycling) and haemoglobin (cross-country skiing) limits have been set by international sporting federations (haematocrit 50%, haemoglobin 18.5 g/dl). Athletes tested above these cut-off values are declared unfit for competition. To investigate the validity of these regulations, we studied haemoglobin, haematocrit and red blood cell indices of elite cyclists before erythropoietin became commercially available. MATERIAL AND METHODS: We investigated 523 blood samples of 92 male elite cyclists (age 16-31 years) from 1978 to 1987. Haematocrit, haemoglobin and red blood cell count were analysed automatically, erythrocyte indices were calculated. RESULTS: Haemoglobin (-0.3 +/- 1 g/dl), haematocrit (-1.2 +/- 2.8%) and red blood cell count (-0.2 +/- 0.4 x 10(6)/mm3) decreased significantly (p < 0.05) with increasing training workload. The erythrocyte indices showed no significant change. Fifty-four blood samples (10.3%) showed a haematocrit above 50%, one sample presented a haemoglobin mass higher than 18.5 g/dl. During periods of increased workload, less athletes tested above the haematocrit limit. CONCLUSION: The current haematocrit limit used in blood tests might lead to a high number of false positive tests.


Subject(s)
Bicycling/physiology , Doping in Sports , Hematocrit/statistics & numerical data , Hemoglobins/analysis , Adolescent , Adult , Erythrocyte Count/statistics & numerical data , Humans , Male , Reference Values , Skiing
15.
Clin Rheumatol ; 19(4): 253-7, 2000.
Article in English | MEDLINE | ID: mdl-10941802

ABSTRACT

Fibromyalgia (FM) is a disorder characterised by diffuse widespread musculoskeletal aching and stiffness and multiple tender points [1]. Its pathophysiology is poorly understood. The influence of aerobic endurance exercise on pain in patients with FM was investigated. Twenty-seven patients (25 female, 2 male) participated in a controlled clinical study and performed 12 weeks of jogging, walking, cycling or swimming following a given schedule. Twelve sedentary FM patients (11 female, 1 male) served as controls. Before and after training both the study and the control groups were evaluated spiroergometrically. Tender point pain was quantified by dolorimetry. The painful body surface was estimated by a pain body diagram, and its intensity by a visual analogue scale and a ranking scale. Patients trained for an average of 25 min two to three times a week, with an average intensity of 50% of maximal oxygen uptake (VO2max). Unlike the control group, the training group exhibited a decrease in heart rate and VO2 and an increase in respiratory quotient during submaximal workload. Maximal performance capacity and VO2max remained unchanged, whereas the wattpulse (watt/heart rate) improved at maximal workload. Pain parameters remained unchanged in the control group, but in the training group the mean number of positive tender points (15.4/12.7), the mean pain threshold of the gluteal tender point (2.89 kp/3.50 kp) and the painful body surface (18%/15% body surface) decreased significantly. Subjective general pain condition deteriorated in two patients but improved in 17. Our results suggest a positive effect of aerobic endurance exercise on fitness and well-being in patients with FM.


Subject(s)
Exercise , Fibromyalgia/therapy , Adult , Bicycling , Data Interpretation, Statistical , Exercise Test , Female , Fibromyalgia/metabolism , Fibromyalgia/physiopathology , Heart Rate , Humans , Jogging , Male , Middle Aged , Pain/physiopathology , Pain Measurement , Pain Threshold , Physical Endurance , Spirometry , Swimming , Time Factors , Walking
16.
Clin Physiol ; 20(4): 304-10, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10886263

ABSTRACT

Persons with spinal cord injury (SCI) are especially prone to atherogenesis. This is partly explained by an unfavourable lipoprotein profile in these individuals. The impairment of the sympathetic nervous system, and the fact that SCI subjects are subject to extreme physical inactivity, may have an influence on their lipid profile and lipoprotein(a) concentration. We made a detailed investigation of the lipid profile as well as serum levels of adrenaline and noradrenaline in 80 men with SCI ranging from tetraplegia to low paraplegia and in 16 control subjects. The lipid profile of tetraplegics was characterized by elevated very low-density lipoprotein cholesterol and triglyceride levels and reduced high-density lipoprotein levels. In contrast, paraplegics had significantly higher low-density lipoprotein and total cholesterol levels. Tetraplegics had lower and the low-lesion paraplegics had higher adrenaline and noradrenaline levels than the high-lesion paraplegics and the control subjects. High-lesion SCI subjects also showed an extreme reduction in VO2max. The lipoprotein profile was dependent on the injury level and serum catecholamine concentrations. The lower the noradrenaline values, the lower the high-density lipoprotein cholesterol. The low-density lipoprotein also correlated to catecholamines and particularly adrenaline values. Despite the correlation between lipoprotein(a) and adrenaline, no significant differences in lipoprotein(a) were found within SCI individuals as well as between SCI individuals and control subjects, indicating the predominantly genetic determination of lipoprotein(a) and thus the cardiovascular risk. Different serum catecholamine levels due to impairment of sympathetic nervous system and VO2max levels were observed in SCI subjects. This was associated with a higher lipid risk profile for cardiovascular diseases; however, the risk profile is dependent on the lesion level.


Subject(s)
Epinephrine/blood , Lipoprotein(a)/blood , Norepinephrine/blood , Spinal Cord Injuries/blood , Adult , Arteriosclerosis/etiology , Humans , Male , Quadriplegia/complications , Risk Factors , Severity of Illness Index , Spinal Cord Injuries/complications
17.
J Appl Physiol (1985) ; 88(5): 1571-5, 2000 May.
Article in English | MEDLINE | ID: mdl-10797114

ABSTRACT

Several studies have reported that the insertion (I) allele of the angiotensin-converting enzyme (ACE) I/deletion (D) polymorphism is associated with enhanced responsiveness to endurance training and is more common in endurance athletes than in sedentary controls. We tested the latter hypothesis in a cohort of 192 male endurance athletes with maximal oxygen uptake >/=75 ml. kg(-1). min(-1) and 189 sedentary male controls. The ACE ID polymorphism in intron 16 was typed with the three-primer polymerase chain reaction method. Both the genotype (P = 0.214) and allele (P = 0.095) frequencies were similar in the athletes and the controls. Further analyses in the athletes revealed no excess of the I allele among the athletes within the highest quartile (> 80 ml. kg(-1). min(-1)) or decile (>83 ml. kg(-1). min(-1)) of maximal oxygen uptake. These data from the GENATHLETE cohort do not support the hypothesis that the ACE ID polymorphism is associated with a higher cardiorespiratory endurance performance level.


Subject(s)
DNA Transposable Elements , Gene Deletion , Peptidyl-Dipeptidase A/genetics , Physical Endurance/physiology , Polymorphism, Genetic/genetics , Sports , Alleles , Cohort Studies , Genotype , Humans , Male , Oxygen Consumption , Reference Values
18.
MAGMA ; 10(1): 27-34, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10697223

ABSTRACT

The purpose of this study was to scrutinize the ability of magnetic resonance imaging (MRI)-performed measurements to compare arterial flow patterns in patients with peripheral arterial occlusive disease (PAOD), healthy volunteers (HV) and endurance athletes (EA). MRI blood flow data were partially repeated with Doppler ultrasound (DUS) with a view to a methodical comparison. Additionally, pulse wave velocity was assessed with the MUFF technique. For this purpose, MRI-performed flow measurements were performed in the common femoral artery in 21 patients with PAOD, in 34 HV and in 12 EA. The analysis included maximum flow velocities (MFV), velocity/time profile (VTP), pulse wave velocity (Vpulse), and vessel diameter (VD). In addition, MFV and VD were observed by DUS in most individuals. The results revealed a significant change regarding arterial blood flow characteristics in patients compared with HV and EA, with respect to the span between the peak positive and negative blood flow velocity in the femoral artery. The pulse wave velocity in patients was markedly elevated compared with healthy individuals. Furthermore, a complete, characteristic change in the VTP could be observed in patients. The methodical comparison between DUS and MRI showed a good correlation. Multi-slice Fourier flow data have indicated markedly increased pulse wave velocity in PAOD patients. Changes in the arterial blood flow can be clearly observed with MRI. In the future, this might offer a noninvasive possibility not only for the evaluation of the stage of the disease, but also for the detection of early, pre-clinical stages of atherosclerosis.


Subject(s)
Arterial Occlusive Diseases/physiopathology , Arteries/physiology , Arteriosclerosis/physiopathology , Magnetic Resonance Imaging/methods , Sports/physiology , Adult , Aged , Arteries/physiopathology , Blood Flow Velocity , Diastole , Female , Fourier Analysis , Heart Rate , Humans , Male , Middle Aged , Physical Endurance , Reference Values , Regression Analysis , Systole , Ultrasonography, Doppler
19.
Int J Sports Med ; 20(7): 464-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10551342

ABSTRACT

A dyslipoproteinemia of increased concentrations of small, dense LDL particles and reduced HDL2 cholesterol has shown to be associated with coronary heart disease (CHD). In contrast, an increase in physical fitness and a reduction of body mass index (BMI) improve the lipoprotein profile and reduce the incidence of cardiovascular events. The association of physical exercise, physical fitness, and body weight with an atherogenic lipoprotein subfraction profile has been investigated before in obese subjects, but the relationship is unknown in a healthy non-obese population without insulin resistance or CHD. Therefore, a detailed lipoprotein subfraction profile of 3 HDL and 6 LDL subfractions was determined in 125 healthy men (26+/-5 years). Physical fitness (maximal oxygen consumption, VO2max) was assessed by ergometry and physical activity by questionnaire. Those men with the lowest physical fitness (VO2max < 40 ml/kg/min) and the lowest physical activity score had a significantly less favourable lipoprotein subfraction profile of increased concentration of small, dense LDL particles (d: > 1.044 g/ml) and reduced HDL2a cholesterol than those with a VO2max >50 ml/kg/min. Multivariate regression analysis revealed that concentrations of small, dense LDL particles were primarily determined by BMI whereas HDL2a cholesterol and apolipoprotein A-I were primarily determined by physical fitness. These findings underline the relationship between a good physical fitness, a low body weight, and a favourable lipoprotein subfraction profile even in a healthy young male population.


Subject(s)
Cholesterol, HDL/blood , Cholesterol, LDL/blood , Physical Fitness/physiology , Adult , Body Weight , Cardiovascular Diseases/etiology , Health Status , Humans , Male , Oxygen Consumption , Risk Assessment
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