The effects of motor adaptation on ankle isokinetic assessments in older drivers

OBJECTIVES: This study sought to analyze the extent of motor adaptation in ankle plantar flexors and dorsiflexors among older drivers during clinical isokinetic testing. METHODS: One hundred older adults (70.4±5.7 years) participated in two bilateral ankle plantar flexor and dorsiflexor isokinetic assessments at 30°/sec. Peak torque (PTQ), PTQ adjusted for body weight (PTQ/BW), and total work (TW) were analyzed. RESULTS: On the dominant side, PTQ/BW and TW were significantly greater for the second plantar flexion test than were those for the first such test (p<0.001), whereas PTQ, PTQ/BW, and TW (p<0.001) were significantly greater for the second dorsiflexion test than were those for the first such test. On the non-dominant side, plantar flexion PTQ and TW were significantly lower for the second test than were those for the first test (p<0.001). CONCLUSION: Older drivers demonstrated better performance with the dominant limb on the second test. The low variability in test execution showed the existence of a motor adaptation effect for the tested movements, despite the short recovery period between the assessments.

Quantitative evaluation of trunk muscle strength in wheelchair basketball players

Trunk muscle strength affects trunk controlling playing an important role in performance and to define the classes of wheelchair basketball players. Trunk control capacity differs among players and quantitative assessments of trunk muscle strength have not been investigated. The aim of this study was to identify and correlate quantitative measures of trunk muscle strength with the wheelchair basketball players' classification. Forty-two male wheelchair basketball players with spinal cord injury, amputation, post-poliomyelitis sequelae, and cerebral palsy had their trunk extension and flexion strength evaluated with isokinetic dynamometer. The classes 1.0, 2.0, 3.0, and 4.0 were considered for statistical analysis. Comparison of trunk muscle strength differed significantly between classes: 1.0 and 3.0; 1.0 and 4.0; 2.0 and 3.0; and 2.0 and 4.0. High correlation was found between the trunk muscle strength and players' classes. The findings of the present study showed a strong correlation of trunk muscle strength and wheelchair basketball classes being able to distinguish players in their classes. However, this quantitative method of evaluation of the trunk muscle strength cannot be solely used to make a decision on the full trunk control

The influence of anthropometric factors on postural balance: the relationship between body composition and posturographic measurements in young adults

OBJECTIVE: The aim of the present study was to evaluate the influence of anthropometric characteristics and gender on postural balance in adults. One hundred individuals were examined (50 males, 50 females; age range 20-40 years). METHODS: The following body composition measurements were collected (using bone densitometry measurements): fat percentage (% fat), tissue (g), fat (g), lean mass (g), bone mineral content (g), and bone mineral density (g/cm2). In addition, the following anthropometric measurements were collected: body mass (kg), height (cm), length of the trunk-cephalic region (cm), length of the lower limbs (cm) and length of the upper limbs (cm). The following indices were calculated: body mass index (kg/m²), waist-hip ratio and the support base (cm²). Also, a postural balance test was performed using posturography variables with open and closed eyes. RESULTS: The analysis revealed poor correlations between postural balance and the anthropometric variables. A multiple linear regression analysis demonstrated that the whole group (female and male) height explained 12% of the medial-lateral displacement, 10% of the speed of oscillation, and 11% of the displacement area. The length of the trunk-cephalic length explained 6% of the displacement in the anteroposterior direction. With eyes closed, the support base and height explained 18% of the medial displacement, and the lateral height explained 10% of the displacement speed and 5% of the scroll area. CONCLUSION: Measured using posturography, the postural balance was only slightly influenced by the anthropometric variables, both with open and closed eyes. Height was the anthropometric variable that most influenced postural balance, both in the whole group and separately for each gender. Postural balance was more influenced by anthropometric factors in males than females.

Motivaçäo no esporte infanto-juvenil: uma discussäo sobre razöes de busca e abandono da prática esportiva entre crianças e adolescentes / Motivation in youth sports: a discussion about the reasons that children and teenagers look for and quit sports practice

O objetivo deste estudo foi determinar, através dos dados da literatura, quais fatores estariam influenciando a motivaçäo das crianças e adolescentes no que tange à prática esportiva. O principal questionamento colocado foi: por que diariamente milhares de crianças e adolescentes iniciam ou abandonam a prática esportiva? Observou-se que os fatores que determinam tais atitudes variam conforme a idade e o sexo. Geralmente,os principais motivos alegados por crianças e adolescentes para in iciar-se e persitir na prática esportiva foram: diversäo, bem-estar físico, competiçäo e novas amizades. Já os principais fatores alegados para oabandono da prática foram: falta de competiçäo, ênfase exagerada na vitória e excesso de pressöes por parte dos pais e dos técnicos. Seria de grande importância que pais, técnicos e dirigentes esportivos se sensibilizassem com tais questöes a fim de que cada vez mais crianças vivenciassem longos períodos de prática esportiva. (au)