Bahram Ghafari; Mehdi Shahbazi; Mehdi Aghapour; Elham Shirzad
Abstract
Meta-stability is a relatively stable region in which system components tend to cooperate to reach performance goals of movement while maintaining their separate and flexible characters. Participants were assigned to 3 skill groups: coordination (n=10), coordination control (n=10), and optimized ...
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Meta-stability is a relatively stable region in which system components tend to cooperate to reach performance goals of movement while maintaining their separate and flexible characters. Participants were assigned to 3 skill groups: coordination (n=10), coordination control (n=10), and optimized control (n=10). Each two fencers fought in each group. Results of cluster analysis and empirical density indicated the emergence of a metastable region in coordination control group (between 1.689276- 2.270372), two metastable regions in optimized control group (between 0.9824658- 1.00113699 and 1.843131-2.333738) and no metastable region in coordination group. Moreover, the binomial test showed that the proportion of using modes of actions in metastable regions in coordination control and optimized control groups had no significant difference (P=0.4888). But the extent of metastable region in the coordination control group was significantly greater. Findings of this study showed that fencers' motor system is metastable depending on their skill level and the extent of metastable regions was different in each level. To design learning and organizing practice, sport coaches can lead the athletes to metastable regions to emerge the most functional motor responses.
Masoud Zahiry; Shahrzad Tahmasebi Borujeni; Mehdi Aghapour; Nastaran Majdi Nasab
Abstract
Challenge point framework is a theoretical framework to understand the effects of exercise variables in motor learning. According to this framework, contextual interference and knowledge of results (KR) feedback have a close relationship with the skill level and task difficulty. So, the aim of ...
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Challenge point framework is a theoretical framework to understand the effects of exercise variables in motor learning. According to this framework, contextual interference and knowledge of results (KR) feedback have a close relationship with the skill level and task difficulty. So, the aim of this study was to investigate the effect of exercises based on challenge point framework on postural control in patients with multiple sclerosis. The postural control of 22 MS patients (age range 20 - 65 years) from patients of Ahvaz MS Association who were randomly selected and assigned to experimental and control groups was measured by the force platform. Subjects in the experimental group performed exercise for 12 sessions, 3 sessions per week and 45 minutes each session. The control group did not receive any interventions. The data were analyzed by mixed analysis of variance and analysis of variance with repeated measures (P≥0.05). The findings showed that the postural control of experimental group significantly improved compared with the control group as a result of four weeks of exercise protocol. Also, postural control of the experimental group significantly developed in the posttest compared with the pretest. So this study supported challenge point framework and instructors and practitioners can use this protocol for effective clinical interventions to improve balance and postural sways in MS patients.
