PubMed Health⌕ Search

Biomedical subjects

A Rostan

Publications and source records attributed to A Rostan.

18 recordsLinked to original sources
PubMed1992

[Physical performance and sedation: comparative study of the effects of a benzodiazepine (temazepam) and of a non-benzodiazepine hypnotic (zolpidem)].

It is well-known that many athletes experience some form of precompetition stress that may result in insomnia during the night before their competition. Yet, sleep withdrawal even if only partial, has a negative influence on performance, particularly when the type of exercise requires good psychomotor performance The purpose of the present study was to investigate whether the intake of a hypnotic drug would have negative effects on physical performance capacity. The authors have compared the effects of oral temazepam, a medium half-life benzodiazepine vs oral zolpidem, a short half-life non-benzodiazepine drug, vs placebo. A randomized double-blind trial was used to assess endurance, resistance, strength and coordination in 26 athletes. The results did not show any differences between the three groups, neither in physical performance characteristic nor in coordination. It is concluded that as regards the performance capacity, there is no risk for stressed athletes to use sleep inducers the night before their competition.

Adult↗
PubMed1992

[Study of the type of physical effort exerted by competition in Supercross].

The authors draw up a tentative account of the physiological load a pilot bears during a Supercross event. Examination of heart frequency and blood lactate concentration curves during a series of races shows that this sport is not only highly stressful, but demands by the same token a muscular effort which has to be taken into account. Muscular work is of the mixed type, both aerobic and anaerobic, the share of the latter being of moderate importance, as it depends mainly on the technical proficiency of the driver.

Adolescent↗
PubMed1992

[Sudden death during performance of sport: forensic medicine elucidation].

Our study deals with cases of sudden death (non-traumatic death) while playing sport which were examined at the Institute of Forensic Medicine at the University of Geneva, and covers the last ten years: 1980-1989. We discovered 19 cases, all men between the ages of 17 to 67. In the case of the younger sportsmen (under the age of 45-50) or when the causes of mortality were unclear, the police requested an autopsy, which totalled 8 cases. In the other 11 cases, we were asked to make an external examination of the bodies, in order to exclude any signs of violence. Seven sportsmen, aged 36-49, who used to play high-risk sports such as football, tennis, basketball and running were autopsied and presented a myocardial infarct. Its interesting that 2 of these cases had also an old scar of a myocardial infarct. The eighth case was a 17 year old boy who had an already known obstructive cardiomyopathy.

Adolescent↗
PubMed1990

[Perceived effort: correlation with the anaerobic threshold and usefulness in a training program].

Following the extensive technical progress in monitoring of sports performance, putting certain physiological principles out of reach for the everyday sportsman, we wondered if perceived effort (PE) as described by Borg is a parameter that is of use, or complementary, to the determination of the anaerobic threshold (AT) during an incremental test on a treadmill on one hand and to prescribing exercise adapted to the type of metabolic load on the other. 46 sportsmen (various soccer players, regional runners) were asked to complete a Conconi Test on a treadmill and at the same time were asked to evaluate their PE (as defined by Borg) at each performance level. We then plotted PE as a function of running speed, thus finding a point of inflexion (ascending) for PE. The speed corresponding to this point shows an excellent correlation with the AT as determined from cardiac frequency. The absolute value of PE at the AT varied little within our group, but seemed to vary according to the type of sport and the subjects' sports practice. Taking the limitations of this method in consideration, PE may be used as an additional indicator in the determination of the AT in an incremental AT-test and can be useful in the prescription of an exercise program.

Adolescent↗
PubMed1989

[Blood pressure values during an exercise test].

High blood pressure readings are relatively frequent during dynamic exercise testing. However, because of the paucity of date concerning normal blood pressure values during exertion and the prognostic significance of exertion hypertension, the attitude to be adopted towards such patients is ill-defined. The present study proposes mean values for BP at a given workload, per age group (less than 20, 20-39, 40-59, greater than 60) and per sex. These values were computed from measurements during dynamic exercise tests performed by 303 subjects (177 male, 126 female) at 100 and 150 watts workloads. Systolic and diastolic pressures during exertion correlated positively with resting blood pressure values (p less than 0.001) and increased with age (p less than 0.001). Hypertension during exertion was defined as values more than 2 SD above mean values for the corresponding age group and sex. 20 subjects met these criteria in our study.

Adaptation, Physiological↗
PubMed1989

[Scientific training of competition swimmers: contribution of lactic acid level].

This study tries to find a way of improving the effectiveness of the training schedule for swimmers. We regularly measured the level of blood lactate during training in order to estimate as precisely as possible the anaerobic threshold in swimming. As is already known sportsmen improve more rapidly their physical capacity (especially endurance) when they swim at a threshold speed corresponding to 4 Mmol of lactate. We used the following parameters: blood lactate concentration in relation to swimming time, and blood lactate accumulation in relation to covered distance for successive days of training at the same swimming speed. These two complementary procedures allowed us to follow the state of training of each athlete using simple graphs and to better advise him so that he may attain his threshold swimming speed. We have often noticed an improvement of the physical condition: either as an increase in swimming speed for the same accumulation of lactate, or as a decrease in the level of blood lactate for a same swimming speed. Measurements of blood lactate accumulation in relation to covered distance, on the condition that the speeds are more or less the same, allow a more precise estimate of the athletes' performances.

Adolescent↗
PubMed1986

[Role of micro-ruptures in muscular lesions. Definition, pathogenesis, diagnosis and treatment].

In the mind of the public (and unfortunately sometimes in that of the physician also) muscular lesions are too often attributed to pulled or torn muscles. Experience and new theoretical knowledge (particularly microscopic studies) have made it possible to pinpoint the two concepts of microruptures and of true muscular stiffness, which already corresponds to a microscopic lesion of the muscular tissue. An attempt is made to define these two types of lesion, relate them to the "classical" muscular lesions, analyze the pathogenesis and outline their treatment.

Adult↗
PubMed1983

Bilateral fractures of femoral neck in patients with moderate renal failure receiving fluoride for spinal osteoporosis.

Two patients with moderate renal failure sustained spontaneous bilateral hip fractures during treatment with fluoride, calcium, and vitamin D for osteoporosis. They had been taking sodium fluoride (40-60 mg/day) for 11 and 21 months, respectively. Histological examination of a specimen of the bone showed severe fluorosis in the first case, and quantitative analysis of bone showed osteomalacia and skeletal fluorosis in the other case. These abnormalities were considered to be the consequence of excessive retention of fluoride due to renal insufficiency. As bilateral femoral neck fractures are very rare these data suggest a causal link between fractures and fluoride in patients with renal failure. Thus fluoride should be given at a lower dosage, if at all, to patients with even mild renal failure.

Aged↗
PubMed1979

[Edema, heavy legs and popliteal compression].

Fifty patients with edema and heaviness of the lower limbs lacking any general or local explanation were investigated by a plethysmographic method to detect venous stasis of the calf. In 27 of them, hyperextension of the knee produced venous stasis, which was only elicited in one of 39 normal subjects. In 9 patients with edema of systemic origin there was no stasis when the knee was extended. Intermittent venous stasis due to hyperextension of the knee therefore appears to be a causal phenomenon in many cases of edema of unknown origin. A popliteal cyst was found in 9 of 16 patients who underwent knee arthropathy. Further studies are necessary to determine what mechanisms may produce venous stasis when the knee is placed in hyperextension.

Adult↗
PubMed1979

[Popliteal cysts: unusual form of presentation].

Popliteal cysts are usually associated with abnormalities of the knee joint such as osteoarthritis, chronic inflammation or cartilage tears. 15 patients with popliteal cysts demonstrated by arthrography are described who had no obvious lesion of the knee. They had consulted their physician for symptoms without a clearcut relation to the knee joint, such as tenderness on the external side of the calf, ankle edema or paresthesia in the toes. Standard X-rays and clinical examination of the knee were normal except for tender swelling of the popliteal area. The symptoms improved after injection of triamcinolone into the knee joint. Unexplained symptoms of the lower leg may be due to popliteal cysts even in the absence of obvious knee pathology.

Adult↗