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Most injuries that dancers sustain are to the lower extremities, specifically the foot and ankle region. Numerous potential risk factors have been examined for dancer injuries such as technical mistakes and fatigue. The purpose of this study was to compare landing kinematics and kinetics during jumps that are common in dance pre and postfatigue. Ten adolescent advanced level dancers participated in this study. Subjects completed 3 split leaps and 3 center leaps before and after a fatigue protocol performed on a stationary bike. Live motion capture was used to record landing kinematic and kinetic data. Results of this study showed a significant increase in ankle eversion and external rotation angles for center leaps from pre- to postfatigue protocol (P = .020 and P = .020, respectively) as well as significant increases in ankle eversion and knee adduction moments for center leaps (P = .020 and P = .036, respectively). These results show that after a fatigue protocol, there are changes to the kinematics of dancers that may make them more susceptible to ankle injury.

Balance training paradigms have been shown to effectively reduce fall risk. Visual feedback is an important sensory mechanism for regulating postural control, promoting visual perturbations for balance training paradigms. Stroboscopic goggles, which oscillate from transparent to opaque, are a form of visual perturbation, but their effect on standing balance has not been assessed. In this study, 29 participants stood in bilateral and tandem stances as the center of pressure was recorded for 6 consecutive minutes wherein there were no stroboscopic perturbations in the first and last minutes. Spatial–temporal, frequency domain, and nonlinear standing balance parameters were calculated for each period. More differences in spatial–temporal parameters due to the strobe were found in the medial–lateral direction than the anterior–posterior direction. More differences in frequency domain parameters were observed in the anterior–posterior direction than the medial–lateral direction, but this did not occur for each variable. The nonlinear parameters were strongly affected by the strobe. Stroboscopic perturbations did not affect the bilateral and tandem stances equally. Spatial–temporal parameters for the tandem stance were greater in magnitude during the strobe period than the no strobe periods. This effect was not seen with the bilateral stance. This indicates that the efficacy of stroboscopic perturbations for challenging standing balance depends on task difficulty. Balance training paradigms that utilize stroboscopic perturbations will need to harmonize these perturbations with task difficulty.

The stiffness of the supporting leg may alter the energy transfer to the trunk and lower extremities of the kicking leg, which may affect kick performance. This study aimed to clarify whether the stiffness of the supporting leg affects the trunk kinematics during kicking and kicking performance in soccer players. Twenty-two male collegiate soccer players participated in the study. The data for the stiffness properties of the supporting leg and trunk kinematics were obtained and calculated using a 3-dimensional motion analysis system. The results showed that a greater leg stiffness of the supporting leg was associated with a lower trunk rotation angle during kicking. There were no significant correlations between the maximum swing speed and the stiffness of the supporting leg (P < .05). These results suggest that stiffness of the supporting leg may restrain trunk rotation during the kicking motion. However, the lack of a relationship with swing speed indicates the need for further investigation into its effects on kicking performance.

This study investigated the effects of two physical exercise programs for adults with intellectual and developmental disabilities. Twenty-one participants were assigned to an indoor group (IG, n = 7; 24-week gym intervention with machine), an outdoor group (OG, n = 7; 24-week outdoor intervention with low-cost materials) or a control group. The outcomes assessed included quality of life, dementia, and functional capacity. The IG significantly improved physical well-being compared with the control group (p = .017). There were no significant differences in dementia score between groups and moments. Postintervention, the IG showed improvements compared with the control group for the 30-s sit-to-stand test (p = .03), timed up-and-go (p = .00), and 6-min-walk test (p = .033) and between moments in the IG for 30-s sit-to-stand test (pre ≠ post; p = .007) and 6-min-walk test (pre ≠ post; p = .007). Outdoor interventions appeared effective for physical well-being, while indoor interventions using weight-training machines benefited functional capacity. No significant effects were observed for dementia/cognitive decline.