Impact of physical training on the ultrastructure of midthigh muscle in normal subjects and in patients treated with glucocorticoids.

Exercise-training might be a logical method to reverse muscle atrophy and weakness in patients treated with glucocorticoids. The purpose of the present investigation was to establish whether a treatment with low dose prednisone (10 +/- 2.9 mg/d) modulates the effect of a moderate strength type isokinetic training during 7 wk (21 sessions of 20 min) on "muscle efficiency" (power output/muscle mass) and on concomitant changes in ultrastructure of the thigh muscle measured by quantitative electron-microscopic morphometry. Training caused a similar increase in "muscle efficiency" in patients on prednisone (n = 9) as in normal volunteers (n = 9). In normal subjects the increase in muscle efficiency was associated with an increase in sarcoplasm, whereas in patients on prednisone the functional improvement was associated with an increase in sarcoplasm, capillaries, and mitochondria content. Thus, a therapy with low dose prednisone does not abrogate training-induced improvement of muscle efficiency but modulates the ultrastructural response of the muscle to the training.

Serotonin uptake inhibition by the monoamine oxidase inhibitor brofaromine.

The selective, reversible monoamine oxidase (MAO) A inhibitor brofaromine inhibits serotonin (5-HT) uptake in animal models in vitro and in vivo. We investigated whether such an effect can be demonstrated at clinical doses in humans by treating three groups of six volunteers with either placebo, 15 mg phenelzine three times a day, or 75 mg brofaromine twice a day in a 2-week experiment. As an indirect, although relevant parameter, binding of 3H-paroxetine to the 5-HT uptake sites on blood platelets was assessed. Moreover, whole-blood 5-HT as a measure of platelet 5-HT, and serum homovanillic acid (HVA) to tentatively estimate MAO inhibition, were determined. Brofaromine reduced 3H-paroxetine binding to platelets compared with placebo by 20%-25% throughout the treatment period, significance being reached on the last treatment day. In contrast, phenelzine tended to increase 3H-paroxetine binding. Both drugs increased whole-blood 5-HT to approximately 140%-150%. Brofaromine moderately and on some days significantly decreased serum HVA, whereas phenelzine only tended to do so. Our results suggest that brofaromine at the clinically used dosage of 150 mg/day does indeed inhibit 5-HT uptake, as evidenced by measurements of 3H-paroxetine binding to platelets.

Long-term effects of physical training on aerobic capacity: controlled study of former elite athletes.

We studied 15-yr changes in physical training, subcutaneous fat, and maximal oxygen consumption (VO2 max) in male former elite athletes (27 long-distance runners and 9 bobsledders) and in a control group of 23 normal men. In 1973, elite athletes all trained vigorously, whereas in 1988 there was a great interindividual variation in physical training. In the lowest tertile of runners' training activity in 1988 (n = 9), the rate of decline in VO2max during the 15 yr was 1.11 +/- 0.15 (SE) ml.kg-1.min-1.yr-1, or 16% per decade, whereas the most active quintile of runners (n = 5) tended to increase VO2max (NS). The remaining 13 runners showed a rate of decline in VO2max of 0.54 +/- 0.14 ml.kg-1.min-1.yr-1, or 7% per decade. The rates of decline were 0.22 +/- 0.12 and 0.56 +/- 0.10 ml.kg-1.min-1.yr-1, or 5 and 11% per decade, in bobsledders and controls, respectively. When normalized for lean body mass instead of body weight, VO2max showed a reduced variability in the rate of decline, with values ranging from 0.00 +/- 0.27 (most active runners) to 0.69 +/- 0.15 ml.kg lean body mass-1.min-1.yr-1 (least active runners). In multiple linear regression analysis, 15-yr changes in mileage, running pace, and truncal fat together explained 51% of variance in the 15-yr change of VO2max normalized for body weight in runners and 41% in all study men. In runners, change in truncal fat was dependent on changes in both mileage and running pace. In the presence of physical training and anthropometric variables in the regression equation, the 15-yr decrease in maximum heart rate was only modestly predictive of the change in VO2max.(ABSTRACT TRUNCATED AT 250 WORDS)

Specificity of leg power changes to velocities used in bicycle endurance training.

Increases in leg power production resulting from 8 wk of bicycle endurance training (30 min/day, 5 times/wk) were studied using an isokinetic dynamometer. In addition, biopsies of vastus lateralis were analyzed to characterize muscle ultrastructural changes. Performance increased on the dynamometer specifically near the estimated average knee angular velocity used during the bicycle training (200 degrees/s). Power measurements were made during the first 5 contractions (maximal power: Pmax) and last 5 contractions (final power: Pend) of 25 and 50 consecutive contractions (at 60 and 240 degrees/s, respectively). Pmax and Pend increased only at 240 degrees/s but not at 60 degrees/s. These increases in Pmax (86 W) and Pend (78 W) resulted primarily from longer torque maintenance but also from increased peak torque during each contraction and were close to the increase in mechanical power output maintained on the bicycle (Pb; 78 W) during the training sessions. The specificity of these changes to the angular velocities used in the bicycle training indicates a neural basis to these adaptations. We suggest that these neural adaptations, coupled with the observed enhancement of muscle mitochondrial and capillary density (+41 and +15%, respectively) underlie the increased ability to maintain power production on a bicycle after endurance training.

Endurance training in humans: aerobic capacity and structure of skeletal muscle.

The adaptation of muscle structure, power output, and mass-specific rate of maximal O2 consumption (VO2max/Mb) with endurance training on bicycle ergometers was studied for five male and five female subjects. Biopsies of vastus lateralis muscle and VO2max determinations were made at the start and end of 6 wk of training. The power output maintained on the ergometer daily for 30 min was adjusted to achieve a heart rate exceeding 85% of the maximum for two-thirds of the training session. It is proposed that the observed preferential proliferation of subsarcolemmal vs. interfibrillar mitochondria and the increase in intracellular lipid deposits are two possible mechanisms by which muscle cells adapt to an increased use of fat as a fuel. The relative increase of VO2max/Mb (14%) with training was found to be smaller by more than twofold than the relative increase in maximal maintained power (33%) and the relative change in the volume density of total mitochondria (+40%). However, the calculated VO2 required at an efficiency of 0.25 to produce the observed mass-specific increase in maximal maintained power matched the actual increase in VO2max/Mb (8.0 and 6.5 ml O2 X min-1 X kg-1, respectively). These results indicate that despite disparate relative changes the absolute change in aerobic capacity at the local level (maintained power) can account for the increase in aerobic capacity observed at the general level (VO2max).

Physiological profile of world-class high-altitude climbers.

The functional characteristics of six world-class high-altitude mountaineers were assessed 2-12 mo after the last high-altitude climb. Each climber on one or several occasions had reached altitudes of 8,500 m or above without supplementary O2. Static and dynamic lung volumes and right and left echocardiographic measurements were found to be within normal limits of sedentary controls (SC). Muscle fiber distribution was 70% type I, 22% type IIa, and 7% type IIb. Mean muscle fiber cross-sectional area was significantly smaller than that of SC (-15%) and of long-distance runners (LDR, -51%). The number of capillaries per unit cross-sectional area was significantly greater than that of SC (+ 40%). Total mitochondrial volume was not significantly different from that of SC, but its subsarcolemmal component was equal to that of LDR. Average maximal O2 consumption was 60 +/- 6 ml X kg-1 X min-1, which is between the values of SC and LDR. Average maximal anaerobic power was 28 +/- 2.5 W X kg-1, which is equal to that of SC and 40% lower that that of competitive high jumpers. All subjects were characterized by resting hyperventilation both in normoxia and in moderate (inspired O2 partial pressure = 77 Torr) hypoxia resulting in higher oxyhemoglobin saturation levels in hypoxia. The ventilatory response to four tidal volumes of pure O2 was similar to that of SC. It is concluded that elite high-altitude climbers do not have physiological adaptations to high altitude that justify their unique performance.

Fifteen-year changes in exercise, aerobic power, abdominal fat, and serum lipids in runners and controls.

To describe effects of past as well as current exercise, aerobic power, and subcutaneous fat on the serum lipid profile, two groups of former elite athletes (N = 27 runners, N = 9 bobsledders) and a control group of normal men (N = 23) were investigated. Analysis of variance indicated a significant effect of the type of sports activity on HDL cholesterol, apolipoprotein A-I, and triglyceride levels and on the LDL/HDL cholesterol and apolipoprotein B/A-I ratios, with the most favorable values seen in runners and the least favorable values seen in controls. Of the 27 former elite runners, one third (N = 9) had given up or strongly reduced training. This subgroup showed the steepest 15-yr decrease (from 1973 to 1988) in maximum aerobic power and the largest 15-yr increase in subcutaneous fat, and the lipid profile (measured in 1988) corresponded more to the one of bobsledders and controls than to the one of runners who had remained active. Separate correlational analyses of all runners (N = 27) and nonrunners (N = 32) showed that, in both cohorts, i) the 1988 measurements of exercise, aerobic power, and subcutaneous fat were more predictive for the lipid profile in 1988 than the corresponding 1973 values, ii) anthropometric characteristics, especially abdominal fat, had a stronger relation with serum lipid concentrations than exercise and aerobic power, and iii) 15-yr changes in anthropometric characteristics were, but 15-yr changes in exercise and aerobic power were not, associated with triglyceride, lipoprotein, and apolipoprotein levels in 1988.(ABSTRACT TRUNCATED AT 250 WORDS)

Muscle fiber types and morphometric analysis of skeletal msucle in six-year-old children.

Needle biopsies from the vastus lateralis of 13 six-year-old Swiss children were analyzed for muscle fiber type populations and morphometrical characteristics. No significant differences existed between the males and females for fiber type distribution, maximum oxygen consumption, or any of the ultra-structural parameters investigated. The vastus lateralis muscle consisted of 19.7% fast twitch glycolytic (FG) fibers, 21.5% fast twitch oxidative glycolytic (FOG) fibers, and 5,9,% slow twitch oxidative (SO) fibers. Maximum oxygen consumption averaged 45.2 ml/kg min-1 when the subjects were considered as a single group. Morphometrically, it was found that the mean volume density of the central mitochondria was 5.54%, the mitochondrial/myofibrillar volume ratio was 6.68%, and the intracellular lipid volume was 0.46%. There was a significant correlation (r=0.69) between the mitochondrial volume density and the distribution of SO fibers as determined histochemically. It was concluded that the fiber type distribution pattern and ultrastructure of skeletal muscle in six-year-old children was not different from normal adult tissue.

Prospective study of psychological development of adolescent female athletes: initial assessment.

PURPOSE: This study aimed at assessing the impact of physical training on psychological functioning at the onset of a prospective study of psychological and somatic maturation of adolescent female athletes. METHODS: Twenty-seven highly trained gymnasts aged 12.7 +/- 1.1 year (mean +/- SD, training load = 18-26 hr/week) and 16 age-matched but moderately trained swimmers (13.0 +/- 0.9 yr, training load 4-15 hr/wk) were submitted to standardized somatic and psychiatric examinations during training camps. RESULTS: Gymnasts were significantly shorter, lighter and thinner (p < 0.001) than swimmers. Their bone age was moderately but significantly retarded (-1.42 +/- 0.99 yr, p < 0.001) in contrast with swimmers in whom it was adequate for chronological age (+0.28 +/- 0.94 year, ns). Only 7.4% of gymnasts had already had menarche in contrast with 50% of age-matched swimmers (p = 0.003). Psychological functioning was considered as normal in all subjects. However, seven athletes including 3/27 gymnasts and 4/16 swimmers (p = 0.394) were considered as subjects "at risk" to develop a manifest mental disorder over time. Ten gymnasts (41.7%) presented with a global delay in psychological maturation, whereas no such case was observed among swimmers (p = 0.015). No correlation could be established between psychological delay and pubertal retardation (p = 0.210). CONCLUSION: Strenuous training in gymnastics for more than 1 yr has so far no detectable interference with the normal maturational events of adolescence. The outcome of athletes at risk to develop psychopathology as well as those with a global delay in psychological maturation who presented as if they were still in the latency period, remains uncertain.

Circulatory counter-regulations induced by continuous administration of nitroglycerin.

In a placebo-controlled, double-blind, cross-over study in seven healthy volunteers, continuous transdermal administration of nitroglycerin over 48 h by means of Nitroderm TTS 10 evoked counter-regulations that interfered with the nitrate effects. These counter-regulations comprised an increase in sympathico-adrenal activity, manifested in elevated plasma levels of adrenaline and noradrenaline, and an internal hemodilution, readily perceptible from the decrease in the hematocrit readings. As a result, several of the circulatory effects of nitroglycerin were no longer in evidence, or much weaker on the second day of the study. The effects concerned were the reduction of systolic and diastolic blood pressure, the increase in heart rate, the prolongation of PEPc, and shortening of LVETc, and the change in digital-pulse morphology (increase in the a/b quotient). On the other hand, the increase in venous distensibility and the decrease in hematocrit were unaltered throughout the observation period. The attenuation of the action of nitroglycerin noticeable 24 h after application of the patches is, therefore, not indicative of any loss of effect of the substance per se, but due to the circulatory counter-regulations, which were largely confined to the arterial side of the circulation and scarcely affected the venous system. One or two hours after removal of the patches, counter-regulations had practically ceased.

[Ergometric validation of a questionnaire on the physical activity in 2 Swiss towns]. / Validation par ergométrie d'un questionnaire sur l'activité physique dans 2 villes suisses.

A questionnaire concerning physical activity used in the National Research Program No. 1A (PNR 1A) was evaluated by using a physical fitness test on an ergometric bicycle. The values of maximum oxygen consumption correspond to different classes of physical activity set up according to the questionnaire (comparison of groups statistically significant). In addition, it appears that maximal oxygen consumption is in direct relation to the intensity of physical activity during leisure hours, whilst the degree of activity connected with professional or household duties is of very little importance.

[Medical significance and requirements of sports]. / Medizinische Bedeutung und Anforderungen des Sports.

Kind and intensity of physical activity with preventive value of degenerative diseases are well known by sports medicine. The core of the problem is the transfer of established knowledge into action and the creation of attractive programs making physical activity an enjoyment and which let us forget the final objective, i.e. prevention of ill health.

Is excessive running predictive of degenerative hip disease? Controlled study of former elite athletes.

OBJECTIVE: To determine the effects of regular long distance running on the state of the hips in later life. DESIGN: Retrospective study of a cohort of elite athletes and a group of normal, healthy, untrained controls examined 15 years after initial testing. SETTING: Research project at school for physical education and sports. SUBJECTS: 27 Former long distance runners (mean age 42), nine former bobsleigh riders (mean age 42), and 23 normal, healthy, untrained men (mean age 35) who had been examined in 1973 and who agreed to re-examination in 1988. MAIN OUTCOME MEASURE: Radiological evidence of degenerative hip disease in 1988. RESULTS: Physiological and exercise characteristics of all subjects had been recorded in 1973, and in 1988 these measurements were repeated together with radiological examination of the hips. An additive radiological index of hip disease based on grades of subchondral sclerosis, osteophyte formation, and joint space narrowing was significantly increased among runners as compared with bobsleigh riders and untrained controls. After adjustment for age the significant effect of type of sports activity remained (p = 0.032). In multivariate analyses age and milage run in 1973 (97 km/week) emerged as independent, significant, and positive predictors of radiological signs of degenerative hip disease in 1988 (p = 0.017 and p = 0.024 respectively). Among runners alone running pace in 1973 rather than milage run was the stronger predictor of subsequent degenerative hip disease. The milage run in 1988 was not particularly predictive of the radiological index, but endurance in 1988 was inversely related to degenerative hip disease seen radiologically. CONCLUSION: Long term, high intensity, high milage running should not be dismissed as a potential risk factor for premature osteoarthritis of the hip.

[Risk of arthrosis of the upper ankle joint in long distance runners: controlled follow-up of former elite athletes]. / Zur Arthrosegefährdung des oberen Sprunggelenkes bei Langstreckenläufern: Kontrollierte Nachuntersuchung ehemaliger Eliteathleten.

To study the potential influence of long-term, high-intensity physical training on premature osteoarthrosis of the ankle joint, we re-examined former members of the Swiss National team from 1973 in retrospective cohort study in 1988. Twenty-seven track and field long-distance runners and orienteers (mean age 42 [95% confidence interval 41-43] years), 9 bobsledders (42 [39-46] years) and a control group of 23 healthy normal men (35 [33-36] years) were investigated. Physiological and exercise characteristics of all subjects had been recorded in 1973, and in 1988 these measurements were repeated together with a rheumatological and radiological examination of the ankle joint. A four-point scale of radiological joint state was used, taking into account the degree of subchondral sclerosis, osteophyte formation and joint space narrowing. In univariate analysis, the long-distance runners, and among them especially the orienteers (n = 10), showed significantly (both p less than 0.05) more radiological signs of degenerative ankle disease than controls. After adjustment for age, this difference disappeared. Age was itself significantly and positively related to radiological degenerative ankle disease (r less than 0.38; p less than 0.01). Orienteers reported significantly more frequently (60 vs 12%; p less than 0,01) functional instability of the ankle joint than track and field runners. Functional and mechanical (clinical) instability were interrelated in our material (r = 0.33; p less than 0.05) but neither of them was significantly related to radiological signs of degenerative ankle disease.(ABSTRACT TRUNCATED AT 250 WORDS)

[Weaning of young smokers using a transdermal nicotine patch]. / Entwöhnung junger Raucher mit Hilfe eines transdermalen Nikotinpflasters.

To assess efficacy and tolerance of a transdermal nicotine system (TNS) as adjuvant to tobacco withdrawal, 112 young, nicotine-dependent cigarette smokers were treated for nine weeks with TNS (n = 56) or placebo (n = 56). Initial doses of nicotine (21 or 14 mg/24 h) were based on previous smoking habits and stepwise reduced to 7 mg/24 h if abstinence was achieved during medication. After treatment, 39.3% of the TNS users were abstinent versus 19.6% on placebo (p less than 0.05). The craving for cigarettes diminished steadily, but not more significantly on TNS medication. Tenseness, difficulty in concentration and feelings of hunger were consistently and in part significantly lessened in the TNS group. The other withdrawal symptoms were not influenced by TNS treatment. Nine-month follow-up cotinine-verified abstinence rates were 12.5% in the TNS and 3.6% in the placebo group (n. s.). Transient mild or moderate erythema at the application site appeared in 20% of the TNS and 6.3% of the placebo group, and 7.1% of the TNS users dropped out because of severe localized erythema. Other mild, transient, systemic side effects reported by 33.9% of the TNS and 26.8% of the placebo users (n. s.) did not lead to drop-outs.