Behavior of the muscle quality index and isometric strength in elderly women

This study aimed (I) to compare the muscle quality index (MQI) and the isometric hip strength between younger and older women, and (II) to determine the relationship of the MQI with the sit-to-stand test (STS) and isometric hip strength in younger and older women. Twenty-eight elderly women (age= 66.2 ± 5.6 years) and twenty younger women (21.2 ± 2.2 years) participated in the study. The following dependent variables were measured: MQI, STS, body composition, and the peak isometric strength of the hip (PF) which was also normalized using three different methods (PF/Body Mass, PF/Fat-Free Mass, and PF/Body Mass^0,335). Older women presented a lower PF in hip flexion, extension and external rotation regardless of the method of normalization (p < 0.001), but the PF of hip abductors and internal rotators was higher for older women (p < 0.05). No significant differences were found in the MQI between older and younger women (p = 0.443). The MQI was negatively correlated with the time in the STS in older women (r = -0.706, p < 0.001) and younger women (r = -0.729, p < 0.001), while the correlations of MQI with isometric hip strength were weaker in older women (r range: -0.082 - 0.556) and younger women (r range: -0.020 - 0.309). MQI is a clinical and practical tool to assess the muscular power of the lower extremities.

Autonomous Motivation as a Mediator Between an Empowering Climate and Enjoyment in Male Volleyball Players

The objective of this work was to analyze a mediation model concerning the perception of an empowering climate generated by a coach and enjoyment through the autonomous motivation of athletes. The sample consisted of 71 elite male volleyball players from six countries. The age range was 14 to 18 years (M = 16.5, SD = 0.96). The relationships between the perception of an empowering climate, autonomous motivation, and enjoyment were positive and significant. The mediation model showed that autonomous motivation acts as a mediator in the relationship between the perception of an empowering climate generated by the coach and the enjoyment reported by the athletes.