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A novel mutation of antithrombin deficiency in six family siblings and the clinical combat

PURPOSE This study was aimed at exploring the transferability of short range of motion (RoM) isokinetic conditioning on quadriceps performance inside and outside the trained range. METHODS Fifty-five women were randomly assigned to one of four groups: G1 (N = 14) and G2 (N = 14) trained concentrically at 30 and 90degrees x s(-1), respectively, whereas G3 (N = 13) and G4 (N = 14) trained similarly but using the eccentric mode. All four groups trained within 30-60degrees of knee flexion. The training paradigm consisted of 4 sets of 10 maximal repetitions, 3x wk(-1) for a total period of 6 wk. Before the training period and 2 d after its termination, the isokinetic work output (Wisk) was assessed within three angular RoM: 85-60degrees (R1), 60-30degrees (R2), and 30-5degrees (R3). Isometric peak extension moment (PM) and rate of force development (RFD) were evaluated at 10degrees, 45degrees and 80degrees. RESULTS Significant increases were observed in the isometric output (at all three angles), Wisk (in R1 and R2), and the RFD (45degrees). The PM increased significantly more in G3 and G4 compared with G1 and G2, evidencing specificity of contraction mode. CONCLUSION These findings point out to the potential benefits of short RoM conditioning, particularly in those cases where, during specific phases of rehabilitation, a wider RoM may be contraindicative.

Background. Studies indicate that the strategy for postural control may be affected by psychological factors, and that young adults respond to perceived threat to stability by increasing their ankle stiffness. The objective of this study was to compare the postural control strategy adopted by young and old adults when faced with postural threat induced by manipulating surface height. Methods. Sixty elderly (mean age 77.5 ± 4.4 years) and 20 young volunteers (mean age 21.5 ± 3.7 years) participated in the study. Movement of the center of pressure (COP) was recorded for 60 seconds with a portable force-plate, as participants stood with eyes open and closed, both at ground level and 85 cm above ground level. Analysis of variance and Tukey–Kramer tests were conducted to determine the effects of age, postural threat, and vision on mean power frequency (MPF), on amplitude variability both in the anterior–posterior (AP) and medio-lateral (ML) directions, and on mean COP sway velocity, with the significance level set at p =.05. Results. Postural threat did not affect COP measures for the young adults, whereas it induced greater changes in MPF in the AP and ML directions in the elderly participants. A similar trend was observed in the elderly group for amplitude variability in the ML direction and for mean COP sway velocity. Conclusions. In comparison with young adults, elderly adults tend to have an exaggerated postural response to conditions that are perceived as threatening to stability. This response involves primarily increases in MPF, with limited compensatory decreases in amplitude variability observed only in the ML direction.