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Biomedical subjects

R Chevalier

Publications and source records attributed to R Chevalier.

8 recordsLinked to original sources

Specific incremental field test for aerobic fitness in tennis.

OBJECTIVES: To compare metabolic and cardiorespiratory responses between subjects undergoing incremental treadmill (non-specific) and tennis field based (sport specific) tests. METHODS: Nine junior competitive tennis players randomly performed two incremental protocols to exhaustion: a treadmill test (TT) and a tennis specific fitness test (FT). The FT consisted of repeated displacements replicating the game of tennis at increasing speed on a court. In both tests, ventilatory variables and heart rate (HR) were determined at the ventilatory threshold (VT), respiratory compensation point (RCP), and maximal loads (max). Blood lactate concentration was determined at the point of volitional fatigue. RESULTS: Percentage (mean (SD)) maximal HR (83.6 (5.1) v 83.0 (2.8) and 92.1 (2.1) v 92.3 (2.1)%, respectively) and percentage maximal oxygen uptake (VO2max) (69.4 (8.1) v 73.5 (6.1) and 84.4 (6.5) v 85.5 (8.7)%, respectively) at the VT and RCP were not different between the FT and TT subjects, whereas VO2max was higher in the FT than in the TT (63.8 (3.0) v 58.9 (5.3) ml/min/kg; p<0.05). Blood lactate concentration (10.7 (3.0) v 10.6 (4.3) mmol/l) did not differ between the TT and FT. CONCLUSIONS: Although cardiorespiratory variables were not different at submaximal intensities between the two tests, VO2max values derived from laboratory measurements were underestimated. Using field testing in addition to treadmill testing provides a better measurement of a player's individual fitness level and may be routinely used to accurately prescribe appropriate aerobic exercise training.

Adolescent↗

Specific incremental test in elite squash players.

OBJECTIVES: To compare cardiorespiratory responses between incremental treadmill (non-specific) and field (sport specific) tests in elite squash players. METHODS: Seven elite players (ranked 1 to 25 in their national federation including the World number 1) randomly performed an incremental treadmill test (TT) and a squash specific graded test (ST) to exhaustion. The ST consisted of repeated displacements replicating the game of squash, at increasing speed on the court. In both tests, ventilatory variables and heart rate were determined at the ventilatory threshold, respiratory compensation point, and maximal loads (max). RESULTS: Heart rate and percentage maximal oxygen uptake (VO2MAX) at the ventilatory threshold and respiratory compensation point were not different between the ST and TT, whereas VO2MAX was higher in the ST than in the TT (63.6 (3.0) v 54.9 (2.5) ml/kg/min; p < 0.001). Time to exhaustion was not different between the ST and TT (1056 (180) v 962 (71) seconds) but correlated with the ranking of the players only in the ST (r = -0.96, p < 0.001). CONCLUSIONS: VO2MAX values derived from laboratory testing were not relevant for accurately estimating fitness in elite squash players. So the ST may be used as an additional test for determination of training intensity. Improved training advice for prescribing aerobic exercise or perfecting stroke technique may result from these results.

Adult↗

[Socioeconomic approach to the practice of in vitro fertilization in the Brittany region in 1993].

AIM OF THE STUDY: to estimate the social and economical point of view of the practice of in vitro fertilization (IVF) in Brittany in 1993. METHODS: we made a prospective study of 152 cases of IVF. We studied the medical history of sterility of the patients, treatments during IVF, hormonal and ultrasound monitoring, oocytes retrieval and embryo transfer, and the screening until beta-hCG > 1,000 UI or evidence of pregnancy with ultrasound scan. After analysing results of IVF, we studied the cost of all these steps, including hospitalization, transports and stoppage. RESULTS: we estimated the mean price of one IVF cycle at 11,084 francs. We analysed the portion of each step in the total cost and discussed with the view of literature. CONCLUSION: the cost of IVF seems reasonable in this context.

Adult↗

Quantitative evaluation of an experimental inflammation induced with Freund's complete adjuvant in dogs.

A chronic inflammation model in dogs was induced by intraarticular injection of Freund's Complete Adjuvant in the stifle. After a primary, acute response during the first 24 hr, a secondary subacute response was observed after a delay of approximately 3 weeks and persisted for several weeks. To evaluate the time course of the inflammatory process quantitatively, we tested more than 100 different parameters. Finally, only four parameters were selected based on practicability and metrological properties, namely, the body temperature, difference in skin temperature, difference in stifle diameter and vertical force exerted by arthritic hind limb measured using a force plate. The main results of the experimentation were the demonstration that these four parameters were sufficiently repeatable, reproducible, and appropriate to be used for quantitative evaluation of the inflammatory process, and that training of both animals and investigators was required. Finally, it was illustrated that an adjuvant periarthritis in dogs can be used to carry out a pharmacokinetic/pharmacodynamic modelling of an antiinflammatory drug.

Administration, Oral↗