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International audience; This study investigated the different strategies exhibited by expert and novice gymnasts in counter movement forward in flight on uneven bars. Eleven gymnasts performed three trials connected with a kip to support. The gymnasts were divided into two groups according to their ability to connect: six able (termed as experts) versus five non-able (novices). The 3D motion data were collected at 250 Hz. Biomechanical parameters were computed at release (release state and angular momentum), during aerial phase (duration, minimum value of the moment of inertia) and at regrasp (total duration and rotation angle). Robustness of the release state was also compared. Significant differences were found between groups in the three phases. The novice gymnasts performed as robustly as expert gymnasts but less efficiently because they released the low bar before their centre of mass passed the horizontal, with a lower vertical velocity, resulting in a lower and shorter aerial phase. They also had a larger minimum moment of inertia in flight. Coaches could help novice gymnasts to decrease their dependency on their robust technique by improving the release angle. Exercises, which may allow novice gymnasts to exceed the threshold of a 90° rotation angle at release are suggested

Following the observation by Brown et al. (Am J Physiol 1997; 272: C937-49) that primary rat adipocytes in culture secrete gelatinase A (MMP-2), we have evaluated gelatinase expression in adipose tissue with the use of mouse models of obesity. Wild-type mice were kept on a standard fat diet (SFD) or on a high fat diet (42% fat, HFD) and- genetically obese db/db mice were kept on SFD; gonadal and subcutaneous fat pads were removed and analysed ex vivo. These studies revealed that: 1) the HFD induced adipocyte hypertrophy; 2) after 32 weeks, significantly higher levels of 70 kDa (p0.05) and 65 kDa proMMP-2 (p0.01) were observed in extracts of gonadal fat pads of mice on HFD; 3) the contribution of active MMP-2 to the total level was comparable in SFD and HFD groups (20 to 30%); and 4) gelatinase B (MMP-9) was not consistently detected. These findings were confirmed by gelatin zymography and by mRNA determination using competitive RT-PCR. The presence of MMP-2 in the adipose tissue was confirmed immunologically and its localization in adipocytes revealed by immunogold electron microscopy. The potential functional role of MMP-2 in adipose tissue remains to be determined.