Josiane Castells

Effects of combined lower body endurance and upper body resistance training on the satellite cell pool in elderly subjects

To distinguish the respective potential of endurance and resistance training to increase the satellite cell pool, we investigated the effects of 14 weeks of concurrent lower body endurance and upper body resistance training (3 sessions/week) on vastus lateralis (VLat) and deltoid (Del) muscles of 10 active elderly men. NCAM+ satellite cells and myonuclear number were assessed in VLat and Del. After 14 weeks of training the NCAM+ satellite cell pool increased similarly (+38%) in both muscles, mainly in type II muscle fibers (P < 0.05). There was no significant change in myonuclear number or myonuclear domain in either muscle. Combining resistance training in the upper limbs with endurance training in the lower limbs is an efficient strategy to enhance the satellite cell pool in upper and lower body muscles in elderly subjects. Our results provide a practical reference for the determination of optimal exercise protocols to improve muscle function and regeneration in the elderly. Muscle Nerve, 2008

Relationship between mean habitual daily energy expenditure and maximal oxygen uptake

A population of 120 healthy voluntary subjects of both genders aged 16-88 was studied using the QAPSE (Saint-Etienne Physical Activity Questionnaire) with the purpose of investigating the factors influencing the relation between MHDEE (mean habitual daily energy expenditure) and VO2max (maximal oxygen uptake) to elucidate the factors accounting for individual variation. The mean of MHDEE obtained was 12,181.9 +/- 4041.9 kJ.d-1. The mean VO2max obtained was 39.9 +/- 13.8 ml.kg-1.min-1. A strong relationship between MHDEE and VO2max (r = 0.916; N = 120; P < 0.0001) was found. Further, MHDEE seemed to be the greater determinant in the variation of VO2max (89.35%). Other variables were found to be involved in the relation between MHDEE and VO2max for a smaller, but still substantial part: age (6.92%), PAST (exathletes who had considerably reduced or stopped their training) (2.45%), body mass (0.85%), and gender (0.43%). Two variables regarding maximal intensity of activity were not included in the multiple-linear regression analysis. These results suggested that the most important factor in the variation of VO2max is the total quantity of energy expenditure and not only the maximal intensity that could reach the subject.

Influence of hypoxic ventilatory response on arterial O2 saturation during maximal exercise in acute hypoxia

AbstractThe aim of this study was to evaluate the influence of peripheral chemosensitivity estimated by hypoxic ventilatory response (HVR) on arterial oxygen saturation (SaO2) during maximal exercise in acute hypoxia. A group of 16 healthy men performed maximal exercise in two conditions of partial pressure of inspired oxygen (PIO2/149 and 70 mm Hg, 19.8 and 9.3 kPa). Measurements of maximal oxygen uptake (

Regulation of Akt-mTOR, ubiquitin-proteasome and autophagy-lysosome pathways in response to formoterol administration in rat skeletal muscle.

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a Methodology to Assess the Accuracy of a Portable Metabolic System (vmaxsttm)

) andSaO2 using an ear-oximeter were carried out in both conditions ofPIO2. The HVR was measured at rest by progressive isocapnic hypoxia and evaluated by the slope of the linear regression between the ventilatory flow (

Evidence for mitochondrial respiratory deficiency in rat rhabdomyosarcoma cells.

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