Using Biomechanics to Explore Children’s Movement
Kathleen M. Knutzen and LeaAnn Martin
H-Reflex Size in Young and Elderly Adults of Varying Physical Activity Levels
Gordon R. Chalmers and Kathleen M. Knutzen
The aim of this study was to determine whether elderly and young adults with similar physical activity levels have similar soleus H-wave maximum/M-wave maximum ratios (H-reflex size) and to determine the relationship between H-reflex size and physical activity level. H-reflex size and physical activity levels were measured in 18 elderly (71 ± 5.7 years) and 20 young (24 ± 4.2) participants. The physical activity levels of the 2 groups were not significantly different. The elderly group had smaller H-rellexes than the young group (elderly. 36% ± 27%; young, 59% ± 17%; p < .05), but the effect of age on H-reflex size was only moderate (omega squared = .19, effect size = .30). There was a weak tendency for higher levels of physical activity to be associated with larger H reflexes (r = .38, p < .05). The findings indicate that soleus H-reflex size is not strongly associated with age or physical activity level.
Biomechanics: 40 Years On
Joseph Hamill, Kathleen M. Knutzen, and Timothy R. Derrick
In the last 40 years, biomechanics has progressed significantly as a subdiscipline within kinesiology. The development of national and international societies dedicated to biomechanics and the increase in the number of scientific biomechanics journals has led to a growth in the biomechanics community. In the last few decades, the research focus in biomechanics has broadened substantially. With this diversity of focus, there have been many novel developments in new technologies used in biomechanics. Biomechanics has become an integral subdiscipline that has interfaced with several other areas in kinesiology and has contributed significantly to enhancing the knowledge base in all areas. Much of the development of biomechanics has resulted from improvements in the technology used in movement research. Although it may be overreaching to say that biomechanics can solve many human movement problems, the technology has allowed researchers to at least answer more comprehensive questions and answer them in greater depth.