Effects over one year of low-intensity endurance exercise targeted at the level of maximal lipid oxidation

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Service Platform for Converged Interactive Broadband Broadcast and Cellular Wireless

A converged broadcast and telecommunication service platform is presented that is able to create, deliver, and manage interactive, multimedia content and services for consumption on three different terminal types. The motivations of service providers for designing converged interactive multimedia services, which are crafted for their individual requirements, are investigated. The overall design of the system is presented with particular emphasis placed on the operational features of each of the sub-systems, the flows of media and metadata through the sub-systems and the formats and protocols required for inter-communication between them. The key features of tools required for creating converged interactive multimedia content for a range of different end-user terminal types are examined. Finally possible enhancements to this system are discussed. This study is of particular interest to those organizations currently conducting trials and commercial launches of DVB-H services because it provides them with an insight of the various additional functions required in the service provisioning platforms to provide fully interactive services to a range of different mobile terminal types

Effets chroniques de l’exercice ciblé au niveau d’oxydation maximale des lipides (LIPOXmax) sur le comportement alimentaire de sujets obèses sédentaires

International audiencePhysical exercise has both a satiating and an orexigenic effect. The latter seems to be favored by glycogen depletion and thus by high intensity exercise. The balance between these two effects is likely to strongly determine the effect of muscle activity on fat loss. Our hypothesis is that the efficiency of training targeted in the zone of maximal lipid oxidation is at least in part explained by alterations in eating behavior. We studied 25 overweight and obese subjects, including 21 women and 4 men. On the whole these subjects lost weight: –2.05 ± 0.8 kg; P < 0.02 and this loss was due to a loss in fat mass (–1.68 ± 0.81 kg; P < 0.05) while FFM was preserved. Five subjects (20%) gained weight (ranging from 0.1 to 1.9 kg), two (8%) had a stable weight and 18 (72%) lost weight (from 0.4 to 21.2 kg). After the first session of training: satiety was unchanged, but hunger was increased (1.15 ± 0.53; P < 0.05) and the subjects were less thinking of food (P < 0.05). Throughout the sessions there was a gradual increase in the satiety score (P < 0.05), and subjects were less thinking of food (P < 0.05). After training, the acute effect of an exercise session on the appetite scale was modified. The acute orexigenic effect (increased hunger) decreases (–1.17 ± 0.40; P < 0.01) as well as the desire to eat (–1.35 ± 0.61, P < 0.05), the amount of food we could eat (–1.25 ± 0.57, P < 0.05) and the will to eat food (–1.78 ± 0.58, P < 0.01). Caloric intake decreased after 8 weeks by 362.69 ± 91.2 kcal/d (P < 0.01) due to a decrease in fat intake (0.17 ± 0.06 g/kg/day; P < 0.02) which was explained in turn by a decrease in the percentage of fat in diet (from 25% to 21% P < 0.05) and reduced snacking that goes from 44% to 18% of subjects tested (P < 0.01). This decrease in snacking is correlated with that of the item “I think about food” on the scale (Spearman rank correlation r = 0.634 P = 0.003). This work therefore shows that LIPOXmax training in obese subjects increases satiety at rest and decreases the orexigenic effect of a single session, and decreased caloric intake and snacking at a correspondingly lower thoughts directed towards the food, resulting in weight loss in 72% of subjects. The slimming effect of training at LIPOXmax seems to be explained at least in part by an increase in satiating effect and decreased orexigenic effect of exercise, resulting in a measurable decrease in calorie intake. These results thus evidence a new mechanism that increases the interest in this variety of training in the management of obesity.L’exercice physique a un effet satiétogène et un effet orexigène, ce dernier semblant favorisé par la déplétion glycogénique et les exercices à haute intensité. L’équilibre entre ces deux effets semble déterminer fortement l’effet de l’activité musculaire sur l’adiposité. Notre hypothèse est que l’efficacité du réentraînement au LIPOXmax s’expliquerait partiellement par une modulation du comportement alimentaire. L’effet chronique de l’entraînement ciblé au LIPOXmax a été étudié chez 25 sujets en surpoids (IMC ≥ 25 kg/m2) et obèses (IMC ≥ 30 kg/m2) dont 21 femmes et 4 hommes. Dans l’ensemble les 25 sujets ont maigri : –2,05 ± 0,8 kg ; p < 0,02 en perdant de la MG (–1,68 ± 0,81 kg ; p < 0,05) et pas de la MM. Cinq sujets (20 %) ont grossi (de 0,1 à 1,9), deux (8 %) ont eu un poids stable et 18 (72 %) ont maigri (de 0,4 à 21,2 kg). L’échelle de Hill est modifiée par la première séance de réentraînement : juste après celle-ci la satiété est inchangée, la faim augmente (+1,15 ± 0,53 ; p < 0,05) et les sujets pensent moins à la nourriture (p < 0,05). Au fil des séances, on voit augmenter le score de satiété (p < 0,05), et les sujets pensent moins à la nourriture (p < 0,05). L’effet immédiat d’une séance sur l’échelle de Hill se modifie. L’effet orexigène aigu de celle-ci (augmentation de faim) diminue (–1,17 ± 0,40 p < 0,01) ainsi que l’intensité du désir de manger. L’envie de manger (–1,35 ± 0,61 ; p < 0,05), et la quantité de nourriture que l’on pourrait manger (–1,25 ± 0,57 ; p < 0,05) et on pense moins à la nourriture (–1,78 ± 0,58 ; p < 0,01). La ration alimentaire des sujets après 8 semaines de réentraînement au LIPOXmax a baissé de 362,69 ± 91,2 kcal/j (p < 0,01) en raison d’une baisse de la ration lipidique de 0,17 ± 0,06 g/kg/j (p < 0,02) ce qui représente une diminution de pourcentage de lipides dans la ration alimentaire passant de 25 % à 21 % (p < 0,05) et une baisse du grignotage qui passe de 44 % à 18 % des sujets testés (p < 0,01). Cette baisse du grignotage est corrélée à celle de l’item (je pense à la nourriture) de l’échelle de Hill (corrélation des rangs de Spearman r = 0,634, p = 0,003). Ce travail montre donc que l’entraînement au LIPOXmax des sujets obèses augmente la sensation de satiété au repos, diminue progressivement l’effet orexigène d’une séance isolée, et diminue la consommation calorique et le grignotage corrélativement à une diminution des pensées dirigées vers la nourriture, déterminant une perte de poids chez 72 % des sujets. L’effet amaigrissant du réentraînement au LIPOXmax semble donc s’expliquer au moins en partie par une augmentation de l’effet satiétogène et une diminution de l’effet orexigène de l’exercice, entraînant une modification mesurable de la prise alimentaire. Ces résultats mettent ainsi en évidence un nouveau mécanisme qui renforce l’intérêt de ce type de réentraînement dans la prise en charge de l’obésité

Prolonged diet-induced obesity in mice modifies the inflammatory response and leads to worse outcome after stroke

BACKGROUND: Obesity increases the risk for ischaemic stroke and is associated with worse outcome clinically and experimentally. Most experimental studies have used genetic models of obesity. Here, a more clinically relevant model, diet-induced obesity, was used to study the impact of obesity over time on the outcome and inflammatory response after stroke. METHODS: Male C57BL/6 mice were maintained on a high-fat (60% fat) or control (12% fat) diet for 2, 3, 4 and 6 months when experimental stroke was induced by transient occlusion of the middle cerebral artery (MCAo) for either 20 (6-month diet) or 30 min (2-, 3-, 4- and 6-month diet). Ischaemic damage, blood-brain barrier (BBB) integrity, neutrophil number and chemokine expression in the brain were assessed at 24 h. Plasma chemokine levels (at 4 and 24 h) and neutrophil number in the liver (at 24 h) were measured. Physiological parameters (body weight and blood glucose) were measured in naïve control- and high-fat-fed mice at all time points and blood pressure at 3 and 6 months. Blood cell counts were also assessed in naïve 6-month control- and high-fat-fed mice. RESULTS: Mice fed a high-fat diet for 6 months had greater body weight, blood glucose and white and red blood cell count but no change in systolic blood pressure. After 4 and 6 months of high-fat feeding, and in the latter group with a 30-min (but not 20-min) occlusion of the MCA, obese mice had greater ischaemic brain damage. An increase in blood-brain barrier permeability, chemokine expression (CXCL-1 and CCL3), neutrophil number and microglia/macrophage cells was observed in the brains of 6-month high-fat-fed mice after 30-min MCAo. In response to stroke, chemokine (CXCL-1) expression in the plasma and liver was significantly different in obese mice (6-month high-fat fed), and a greater number of neutrophils were detected in the liver of control but not obese mice. CONCLUSIONS: The detrimental effects of diet-induced obesity on stroke were therefore dependent on the severity of obesity and length of ischaemic challenge. The altered inflammatory response in obese mice may play a key role in its negative impact on stroke

Composition corporelle mesurée par impédancemétrie segmentaire (BIAS) et performance de sprint chez les rugbymen

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