Plyometric exercise combined with high-intensity interval training improves metabolic abnormalities in young obese females more so than interval training alone

International audienceThe aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6-8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (-11.0% ± 4.7% and -23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (-40.9% ± 10.9%), HOMA-IR (-37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescent

Deep-ultraviolet cavity ringdown spectroscopy

The sensitive optical detection technique of cavity ringdown spectroscopy is extended to the wavelength range 197-204 nm. A novel design narrowband Fourier-transform-limited laser is used, and the technique is applied to gas-phase extinction measurements in CO2, SF6, and O-2. Further demonstration of the system capabilities is given in high-resolution recordings of the Schumann-Runge (0, 0), (1, 0), and (2, 0) bands in O-2. (C) 2004 Optical Society of America

Deception studies manipulating centrally acting performance modifiers: a review.

Athletes anticipatorily set and continuously adjust pacing strategies before and during events to produce optimal performance. Selfregulation ensures maximal effort is exerted in correspondence with the end point of exercise, while preventing physiological changes that are detrimental and disruptive to homeostatic control. The integration of feedforward and feedback information, together with the proposed brain_s performance modifiers is said to be fundamental to this anticipatory and continuous regulation of exercise. The manipulation of central, regulatory internal and external stimuli has been a key focus within deception research, attempting to influence the self-regulation of exercise and induce improvements in performance. Methods of manipulating performance modifiers such as unknown task end point, deceived duration or intensity feedback, self-belief, or previous experience create a challenge within research, as although they contextualize theoretical propositions, there are few ecological and practical approaches which integrate theory with practice. In addition, the different methods and measures demonstrated in manipulation studies have produced inconsistent results. This review examines and critically evaluates the current methods of how specific centrally controlled performance modifiers have been manipulated, within previous deception studies. From the 31 studies reviewed, 10 reported positive effects on performance, encouraging future investigations to explore the mechanisms responsible for influencing pacing and consequently how deceptive approaches can further facilitate performance. The review acts to discuss the use of expectation manipulation not only to examine which methods of deception are successful in facilitating performance but also to understand further the key components used in the regulation of exercise and performance

Processus d'industrialisation de la filière de la viande bovine

An interpretation of the industrialization processes which the beef sector is experiencing. The move over to industry-type processes is mostly controled by farmer's cooperatives with government support. Profits do not seem sufficient to attract private non agricultured investors. Several observations are presented to support this thesis

La démarche marketing dans le domaine de la viande bovine : le cas de la génisse Aubrac-Charolais

Is it possible to make use of a « marketing » approach to solve the problems of a meat producing business ? The writer examines the consequences of the former practices of a small cooperative in the North of the Aveyron, and the problems encountered in introducing a « marketing » approach, problems concerning the estimation of demand, the cooperative regulations, the natural and human environment, the very mixed quality of the young animals, and the various partners lack of awareness of the problems of marketing. A a «marketing» approach brings about a change in the relationships between farmers, farming organizations and the cooperative. A knowledge of the market is the most important factor ; the perfecting of techniques is a secondary consideration

Commercialisation de la viande bovine : problèmes d'application de la démarche marketing

- Marketing techniques are necessary and possible in the beef field, but they are encountering certain difficulties in their application. They are necessary because of the state of the market and the gap that often exists in the modern circuit, between the structure and the strategy of the firms. Whether it concerns a traditional production or baby-beef production, or the processing of these products, marketing implies that consumers' demand should be taken into consideration and that a suitable product should be developed, and sold. The difficulties arise from the structure and behaviour of the firms, the nature of the product and the practices of those who participate in the artisanal circuit

Les AMAP : une alternative socio-économique pour des petits producteurs locaux ?

Les AMAP (Associations pour le maintien des agricultures paysannes) sont des réseaux alternatifs alimentaires de proximité. Une étude est menée en Midi-Pyrénées sur les liens entre producteurs et consommateurs au sein de ces réseaux. Elle vise à saisir les contours de la petite agriculture locale qu’ils défendent. Il ressort que les avantages socio-économiques retirés par le producteur dépendent notamment du partage des coûts de transaction entre acteurs.The AMAP (Associations for the promotion of Peasant Agriculture) take part to the development of local alternative food networks. The results coming from a study carried out in the Midi-Pyrénées region are used to evaluate the socio-economic impacts of the engagement in these networks at the farm level. We show that the relative benefits a producer can get, mainly depend on how transaction costs are shared between the producer and the consumers

Grande distribution alimentaire et changements organisationnels

Over the last 30 years, hypermarkets outlets have become the first beef channel of distribution. At the same time, the beef processing industry has undergone a great development. Thanks to the results of a survey carried out into the main companies from this field of activity, the authors point out all the changes that occurred in the organization of the marketing channel. The structures of beef meat supply and the way they are run show the will of hypermarkets to have a tight control over the dealings that obliges meat suppliers to adjust