Whole-body vibration effects on the muscle activity of upper and lower body muscles during the baseball swing in recreational baseball hitters

The purpose of this study was to evaluate the effects of whole-body vibration (WBV) on the muscle recruitment of selected upper and lower body muscles during the baseball swing. Participants were recreationally trained males (n = 16, 22 +/- 2 years, 181.4 +/- 7.4 cm, 84.7 +/- 9.0 kg), with previous baseball experience. Subjects participated in three randomized sessions on separate days, consisting of three sets of five swings offa hitting tee. Exercises (upper and lower body dynamic and static movements) with or without WBVexposure were performed between swing sets. During each swing, the gastrocnemius, biceps femoris, gluteus maximus, pectoralis major, latissimus dorsi, and triceps brachii were evaluated for electromyographic (EMG) activity. EMG values were normalized to EMG measured during maximal voluntary isometric contraction. Statistical analysis revealed no significant differences in EMG activity across the three treatments. In addition, the results displayed a specific muscle recruitment order during the swing, starting with the lower body followed by the upper body muscles. This study was the first to report the recruitment order during the baseball swing. Although acute exposure to WBV did not significantly alter the muscle recruitment, these results may prove useful for practitioners looking to enhance baseball swing performance.     

Biomechanics and visual-motor control: how it has, is, and will be used to reveal the secrets of hitting a cricket ball

Cricket batting is an incredibly complex task which requires the coordination of full-body movements to successfully hit a fast moving ball. Biomechanical studies on batting have helped to shed light on how this intricate skill may be performed, yet the many different techniques exhibited by batters make the systematic examination of batting difficult. This review seeks to critically evaluate the existing literature examining cricket batting, but doing so by exploring the strong but often neglected relationship between biomechanics and visual-motor control. In three separate sections, the paper seeks to address (i) the different theories of motor control which may help to explain how skilled batters can hit a ball, (ii) strategies used by batters to overcome the (at times excessive) temporal constraints, and (iii) an interpretation from a visual-motor perspective of the prevailing biomechanical data on batting.     

Perspective Paper: Assessing Air Quality as Part of a Physical Therapy Plan of Care

Purpose: The purposes of this clinical perspective paper are (1) to expand physical therapists’ awareness to the topic of air quality as a health priority when providing professional services; and (2) to provide templates for screening the indoor clinical environments and patient profiles to avert respiratory exacerbations, especially in persons with asthma. Summary of Key Points: The location where a physical therapist practices determines the air quality indices to which a person is exposed. Poor indoor air quality can expose a person to even greater compromise of respiration (ie, Sick Building Syndrome) than outdoor air quality secondary to an array of factors like building materials, the ventilation exchange rate of an enclosed space, chemicals used in cleaning, and humidity. Statement of Conclusions: Extrinsic (ie, environmental) and intrinsic (eg, pre-disposition to airway hypersensitivity) factors must be accounted for by physical therapists to safeguard their patients and themselves from experiencing respiratory compromise and/or distress as a result of a treatment session or their place of employment. Recommendations: Efforts to screen indoor environments for potential triggers and patient risk profiles for abnormal airway reactivity should routinely be undertaken. Individualized Action Plans should be prospectively prepared and readied for implementation when warranted.Key Words: asthma, Sick Building Syndrome, indoor air quality, respiratory impairment     

Validation of MET estimates and step measurement using the ActivPAL physical activity logger

The purpose of this study was to determine the validity of the metabolic equivalent (MET) equation and step rate function of the ActivPAL? physical activity logger in a group of females. Using a standard treadmill protocol, 62 females aged 15-25 years walked on a treadmill at speeds between 3.2 and 7.0 km · h(-1) while wearing an ActivPAL. Oxygen consumption was measured using expired gas analysis at each speed and METs for each speed were estimated based on each participant's own resting metabolic rate. A sub-set of 18 participants also wore an Actigraph. Results showed that the in-built equation in the ActivPAL significantly underestimated (P < 0.001) METs under treadmill conditions at higher intensities. The ActivPAL equation is based on step rate yet the relationship between counts and measured METs (r = 0.76; P < 0.001) is stronger than that between steps and measured METs (r = 0.59; P < 0.001). Both the ActivPAL and Actigraph step functions showed no significant difference (P > 0.05) to video recorded step rate except at the slowest walking speed where the Actigraph significantly underestimated steps (P < 0.05). The development of a new equation based on the counts-METs relationship that includes a variety of speeds and activities would be useful. The ActivPAL step function performs better than the Actigraph at the slowest walking speed under treadmill conditions.     

Assessing and Addressing Student Barriers: Implications for Today's College Classroom

The increasingly diverse set of learners in colleges and universities poses considerable challenges for educators. Dorothy A. Osterholt and Sophie Lampard Dennis explain the four domains of learning they have identified and suggest ways to apply them to help students overcome a variety of obstacles to learning.     

Structural and conceptual interweaving of mathematics methods coursework and field practica

This paper describes a study of observed relationships between the design of a preservice elementary mathematics methods course with accompanying field practicum and changes in the extent to which participating prospective teachers identified themselves with the mathematics reform movement after becoming practicing teachers. The curriculum of the course with its embedded field practicum experiences was designed to support prospective teachers in interweaving methods coursework and pedagogical instruction with classroom practice. University and elementary school structures were interwoven by conducting weekly mathematics methods course sessions at a school site followed immediately by related practicum experiences in classrooms in the school. The interweaving of conceptualizations about mathematics teaching and learning was facilitated as the methods instructor provided professional development for classroom teachers simultaneously with the methods course, encouraging the teachers to create “reform-friendly” classroom environments. Survey data from 68 prospective teachers involved in the project were analyzed to identify and describe relationships between course/practicum experiences and the degree to which they as practicing teachers, 1–3 years following the course/practicum, identified with a reform mathematics perspective, as well as to examine factors influencing those relationships.     

Analyzing a service-learning experience using a social justice lens

This mixed methods study explores a service-learning experience embedded in a social foundations course in a teacher education program. The authors differentiate learning outcomes for social justice and charity service-learning, and utilize this framework to examine whether the service-learning experience fosters a social justice perspective. The findings demonstrate that while the experience did foster social justice perspectives for some students, the data also reflect evidence of learning outcomes that align with charity service-learning.