Designing,building, measuring,and testing a constant equivalent fall height terrain park jump

Previous work has presented both a theoretical foundation for designing terrain park jumps that control landing impact and computer software to accomplish this task. US ski resorts have been reluctant to adopt this more engineered approach to jump design, in part due to questions of feasibility. The present study demonstrates this feasibility. It describes the design, construction, measurement, and experimental testing of such a jump. It improves on the previous efforts with more complete instrumentation, a larger range of jump distances, and a new method for combining jumper- and board-mounted accelerometer data to estimate equivalent fall height, a measure of impact severity. It unequivocally demonstrates the efficacy of the engineering design approach, namely that it is possible and practical to design and build free style terrain park jumps with landing surface shapes that control for landing impact as predicted by the theory.     

The effects of short versus long inter-set rest intervals in resistance training on measures of muscle hypertrophy: A systematic review

Although the effects of short versus long inter-set rest intervals in resistance training on measures of muscle hypertrophy have been investigated in several studies, the findings are equivocal and the practical implications remain unclear. In an attempt to provide clarity on the topic, we performed a systematic literature search of PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, and Physiotherapy Evidence Database (PEDro) electronic databases. Six studies were found to have met the inclusion criteria: (a) an experimental trial published in an English-language peer-reviewed journal; (b) the study compared the use of short (≤60?s) to long (>60?s) inter-set rest intervals in a traditional dynamic resistance exercise using both concentric and eccentric muscle actions, with the only difference in resistance training among groups being the inter-set rest interval duration; (c) at least one method of measuring changes in muscle mass was used in the study; (d) the study lasted for a minimum of four weeks, employed a training frequency of ≥2 resistance training days per week, and (e) used human participants without known chronic disease or injury. Current evidence indicates that both short and long inter-set rest intervals may be useful when training for achieving gains in muscle hypertrophy. Novel findings involving trained participants using measures sensitive to detect changes in muscle hypertrophy suggest a possible advantage for the use of long rest intervals to elicit hypertrophic effects. However, due to the paucity of studies with similar designs, further research is needed to provide a clear differentiation between these two approaches.     

Validation of the Kaufman Assessment Battery for Children with a sample of preschool children

The validity of the Kaufman Assessment Battery for Children (K-ABC) (Kaufman & Kaufman, 1983) was investigated with a sample of preschool-age children. The sample consisted of 50 subjects aged 21/2 through 4 who were distributed roughly equally by age, sex, and race according to the 1980 census. The validity of the K-ABC was examined using the Slosson Intelligence Test (SIT) (Slosson, 1982) and the Classroom Behavior Inventory-Preschool Form (CBI) (Schaefer & Edgerton, 1978) as criterion measures. The SIT and CBI-Preschool Form Verbal Intelligence Scale were found to correlate significantly (p<.01) with the global scales of the K-ABC. The K-ABC did not differentiate between age or sex groups, but blacks scored lower than whites. The findings are supportive of previous validity studies (Kaufman & Kaufman, 1983) and two-factor theories of intelligence (e.g., Das, Kirby, & Jarman, 1975).