36 research outputs found
Leptin Level Lowers in Proportion to the Amount of Aerobic Work After Four Weeks of Training in Obesity
Short bouts of anaerobic exercise increase non-esterified fatty acids release in obesity
PURPOSE:
It is demonstrated that aerobic exercise plays an important role in weight loss programs for obesity by increasing 24 h metabolic rate. While aerobic exercise can result in health and fitness benefits in obese subjects, also independently of weight loss, not completely clear are the effects of bouts of hard exercise on metabolic outcomes. The aim of this study was to test the hypothesis that short-term aerobic activity with anaerobic bouts might result in a greater improvement in the management of obesity than aerobic activity alone.
METHODS:
We studied 16 obese subjects (eight men) during a progressive cycloergometric test up to exhaustion, before and after 4 weeks of two different training schedules (6 days/week). Insulin and glycaemia, non-esterified fatty acids (NEFA) and lactic acid were sampled. Group A (eight subjects, four men) performed an aerobic cycle workout; Group B (eight subjects, four men) performed a 25 min aerobic workout followed by 5 min of anaerobic workout. All the subjects maintained their individual eating habits.
RESULTS:
The post-training test showed a decrease in AUCs NEFA in Group A (p < 0.05) and an increase in Group B (p < 0.05), together with an increase in lactic acid in Group A and a decrease in Group B (p < 0.01). \u3b2-cell function (HOMA2-B) revealed a reduction only in Group A (p < 0.05). Group B achieved a greatest reduction in body fat mass than Group A (p < 0.05).
CONCLUSIONS:
Aerobic plus anaerobic training seem to produce a greater response in lipid metabolism and not significant modifications in glucose indexes; then, in training prescription for obesity, we might suggest at starting weight loss program aerobic with short bouts of anaerobic training to reduce fat mass and subsequently a prolonged aerobic training alone to ameliorate the metabolic profile
Use of different statistical methods to assess stability in grapevines
Two trials, conducted in two locations in Italy over 4 years with Chardonnay grapevines trained to GDC, Pergola or Casarsa systems and grafted onto 6 rootstocks (SO4, Kober 5BB, Teleki 5C, 8B, 140Ru and 1103P), provided vine yield and pruning weight data to study a practical and reliable method for assessing genotypic stability. Commonly used stability statistics, like indices based on coefficients of variation and regression, were estimated. When the deviations from regression of genotype performances on the environmental index were large, biological response of rootstocks to different environments was better fitted by double regression analysis based on Verma's coefficients. The unpredictable part of the response in regression approach was quantified by Wricke's ecovalence index. The results confirmed that the use of more than one statistical procedure is necessary in the selection of stable genotypes. Genotype
7 environment interactions were partitioned into four components (variability, ecovalence, linear response or deviation from linear response, environmental sensitivity). The use of a graphical representation of the four components was easy to use and appropriate for grouping genotypes of greater and lesser stability. Rootstocks Teleki 5C and 8B were identified as stable for grape yield, while high yielding genotypes (SO4 and 1103 P) were judged as unstable. 140Ru and Kober 5BB were detected as stable for yield of pruning wood
Genetic optimization of microstrip reflectarrays
Printed reflectarrays try to combine the advantages of both reflectors and printed arrays (see e.g. [l]) and consist in arrays of printed patches, illuminated by a primary feed horn, that re-radiate the illuminating power back into the space. Since the elements have different positions, the field that propagates from the feed to the patches covers different path lengths and therefore the contributions to the total re-radiated field coming from the different patches are not in phase. So it becomes necessary to adjust the phase of the single element to compensate the different path lengths and this may be obtained using at least one of the following different possible techniques: adding to the patches suitable differentlength transmission lines [2, 31, varying the size of the radiating elements [4], rotating the elements to different angles or finally varying the dielectric constant of the material below the radiator itself. Here we chose to combine the first two options togethe
Frequency response of a new genetically optimized microstrip reflectarray
In future, it is conceivable that satellite antennas will need to target a single house. Meeting this requirement, antennas that are larger and lighter must be designed. Example of antennas able to radiate narrow beams are reflector antennas and antenna arrays. Printed reflectarrays combine advantages of both reflectors and printed arrays. They consist in arrays of printed patches, generally of rectangular shape, that re-radiate the illuminating power from a primary feed horn back into space. As the elements have different positions, and the field that propagates from the feed to the patches covers different path lengths, it becomes necessary to adjust the phase of single elements to compensate the different path lengths. We analyze a configuration obtained by varying the length of a stub, the position of the elements and their relative orientation. Moreover, in order to compensate the frequency shift of individual elements introduced by the presence of the stubs, the dimensions of the patches are varied, too. Since the bandwidth of this kind of radiator is it particularly critical issue, a frequency response analysis of the genetically optimized configuration has also been performe