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G Vallet

Publications and source records attributed to G Vallet.

At least 19 recordsLinked to original sources
PubMed1997

Comparison of two training programmes in chronic airway limitation patients: standardized versus individualized protocols.

This study tested the effect of two methods of training, one individualized at the heart rate corresponding to the gas exchange threshold (GET) and the other at the heart rate corresponding to 50% of maximal heart rate reserve, on maximal and submaximal cardiorespiratory response in 24 patients with chronic airway limitation (CAL). The patients were randomly assigned to either the individualized training group (IT; n = 12) or the standardized training group (ST; n = 12). The training programme consisted of 4 weeks of stationary bicycle exercise, 5 days.week-1. Before reconditioning began, the target level based on heart rate was not significantly different between groups (109 +/- 4 versus 110 +/- 3 beats.min-1, in IT and ST, respectively). Post-training, a significant increase in symptom-limited oxygen uptake (V'O2.sl) and maximal O2 pulse was found in IT, whereas ST exhibited no significant change. In each group, GET was statistically increased in much the same way as V'O2,sl, with a higher increase in IT (p < 0.01) than ST (p < 0.05). Nevertheless, IT exhibited a concomitant and gradual decrease in minute ventilation (V'E), carbon dioxide production (V'CO2), and venous lactate concentration ([La]), whereas ST presented no significant change in these parameters (intergroup p < 0.01). Breathing pattern was also altered after IT, at the same metabolic level and at the same ventilation level (intergroup p < 0.05). Cardiac responses were modified in the two groups. At the same metabolic level, a significantly lower cardiac frequency was found both for IT and ST (intragroup p < 0.05 after training). In contrast, the increase in O2 pulse was only significantly higher in It after training. These data show the greater efficiency of an individualized training protocol based on determination of gas exchange threshold as compared to a standardized protocol, in improving exercise performance, when applied to a patient group. Despite an apparently similar target training level, the individualized method clearly optimized the physiological training effects in patients with chronic airway limitation and, more particularly, decreased their ventilatory requirement.

Bicycling↗
PubMed1994

[Value of individualized rehabilitation at the ventilatory threshold level in moderately severe chronic obstructive pulmonary disease].

In order to study the efficiency of individual training programs at the ventilatory threshold level, twenty COPD patients were randomized into two groups and studied over a two-month period. At the start, during, and at the end of the study all subjects performed incremental exercise tests. The trained group (59.60 SEM +/- 2.75 years) walked four times a week at the heart rate corresponding to the metabolic level of ventilatory threshold. The other group served as controls (58.2 +/- 1.80 years). A marked increase in the symptom-limited oxygen consumption (+/- 25%) (p < 0.01), the maximal ventilation (+20%) (p < 0.01), and the ventilatory threshold (+19%) (p < 0.05) was found in the trained group. No modification was recorded in the control group. The ventilatory pattern at submaximal intensities expressed in percentage of the initial oxygen consumption showed significant differences between groups, the trained-group ventilation decreased at 50% and 75% VO2 sl (p < 0.05). The breathing frequency also decreased at 50% and 75% VO2 sl (p > 0.05). Moreover, we observed an increase in the oxygen pulse at 50% VO2 sl (p < 0.05). In conclusion, this study demonstrates that individualized training at the ventilatory threshold level increases exercise tolerance and produces better ventilatory comfort in COPD patients.

Anaerobic Threshold↗
PubMedDate not supplied

Improved skeletal muscle performance after individualized exercise training in patients with chronic obstructive pulmonary disease.

BACKGROUND: In addition to the respiratory limitation in patients with chronic obstructive pulmonary disease (COPD), skeletal muscle abnormalities may occur and contribute to the exercise intolerance. This study assessed the ability of the skeletal muscle of patients with COPD to adapt to individualized exercise training at the gas exchange threshold (GET) METHODS: Fourteen patients (8 in a training group and 6 controls) performed the following exercise tests before and after a 3-week training period: an incremental exercise test, maximal voluntary contraction of the quadriceps, and three endurance tests consisting of dynamic contractions of the quadriceps until exhaustion. These endurance tests, characterized by three different power outputs, were used to determine muscle limit times and critical power. RESULTS: The results showed that training increased exercise tolerance (+11% for symptom limited peak oxygen consumption (VO2 sl], P < 0.05), maximum voluntary contraction (+8%, P < 0.05), limit times (from +45% to +161%, P < 0.05) and critical power (+39%, P < 0.05). CONCLUSIONS: These findings indicate greater muscle strength and endurance after training in COPD patients and suggest better muscular recruitment and improved oxidative capacity in the exercising muscles. The sharp differences in the magnitude of VO2 sl and limit times suggest that the kinetics of peripheral and central changes in response to training are different. In conclusion, peripheral muscle performance can be increased rapidly in response to an individualized training program at the GET in COPD patients.

Exercise Test↗