David Q. Thomas

Event Standardization of Sit-to-Stand Movements

Background and Purpose: Unlike gait analysis, no commonly accepted method for studying sit-to-stand (STS) movements exists. Most previous studies describing STS events used various methods to identify movement events while restricting sitting positions and movements. The present study observed natural rising from a sitting position using a simple method for measuring this common task. The purposes of this study were to compare commonly performed STS movements and to propose a standard system for defining identifiable sequential events. Subjects and Methods: Ground reaction forces of 100 adults who were healthy (50 male, 50 female) were recorded using a force platform as each participant performed 4 methods of rising from sitting on a standard chair. The 4 STS conditions were: with arms free, with hands on knees, using armrests, and with arms crossed. Results: For each subject, 11 recorded events from the vertical, fore-aft, and lateral dimensions were identified for all arm-use conditions. The only significant and clinically relevant force difference among arm-use conditions was that the armrests condition produced less average force than the other 3 conditions during the seat-off and vertical peak force events. Among average event times, the armrests condition showed significantly longer time to the vertical peak force event than the other conditions. Discussion and Conclusion: Because these events occurred invariably in sequential order for every individual for all arm-use conditions in a relatively large sample of observations during natural STS movements, this method may be useful for establishing a standard method to assess and compare patient functionality and allow comparisons among STS research studies.

Changes in Running Economy during a 5-km Run in Trained Men and Women Runners

ABSTRACTResearch indicates that running economy (RE) changes during a 5-km run. However, the mechanisms accounting for this variation have not been identified. This study explored the effects of a 5-km run on the RE, minute ventilation (VE), blood lactate (LA), and core temperature (CT) of 40 distan

Top 10 research questions related to physical activity and bone health in children and adolescents.

Evidence strongly supports a positive, causal effect of physical activity on bone strength and suggests long-term benefits of childhood physical activity to the prevention of osteoporosis. The contribution of healthy bone development in youth is likely to be as important to fracture prevention as the amount of late adulthood bone loss. Families, schools (particularly physical education), and communities are key settings for health promotion focused on bone-enhancing physical activity. However, little research has explored the topic of health promotion and physical education as they pertain to bone health, so best practices are not known. Based on our understanding of the literature, we present the top 10 research questions in health promotion and physical education that should be answered to advance bone-enhancing physical activity in children and adolescents.

Physiologic profile of the fitness status of collegiate cheerleaders

Cheerleading, traditionally considered a nonathletic activity, has evolved into a competitive sport requiring high levels of fitness. Despite the trend of cheerleaders performing increasingly difficult and athletic skills, very little is known about their fitness levels. The purpose of this study was to provide a physiological profile of the fitness status of a squad of collegiate cheerleaders. Eighteen cheerleaders (11 men and 7 women) participated in this study. Each subject completed a Bruce protocol maximal treadmill test, underwater weighing, 1 repetition maximum bench press, sit-and-reach test, push-ups, curl-ups, and isokinetic strength testing. The mean and SD were calculated to provide the physical fitness profile for each parameter. A comparison to normative data demonstrated that cheerleaders have a high level of fitness and scores similar to other collegiate athletes.

Fitness knowledge, cardiorespiratory endurance and body composition of high school students

Summary Study aim: The purpose of this study was to determine if high school physical education seniors’ health-related fitness knowledge is related to their aerobic capacity and body composition. Material and methods: The FitSmart test assessed students (n = 171) health-related fitness knowledge. Aerobic capacity was calculated based on the students PACER score. Body Composition was measured using the Tanita TBF 300A body composition analyzer. Results: Aerobic fitness was a statistically significant predictor of exam score (β = 0.563, p < 0.001), but percent body fat was not (β = 0.185, p =0.074). Comparing the health-related fitness exam scores by the FITNESSGRAM classification system, students who were classified as Very Lean and High Risk for body composition had lower exam scores than those classified in the healthy fitness zone. Conclusions: The results confirmed previous findings that students have inadequate health-related fitness knowledge. Furthermore, the study extends these findings by identifying some associations of percent body fat and estimated VO2max to health-related fitness knowledge.

Exertional Rhabdomyolysis: What Is It and Why Should We Care?.

JOPERD • Volume 83 No. 1 • January 2012 E xertional rhabdomyolysis gained increased attention last year when 13 football players from the University of Iowa developed this condition. On January 25th, 2011 it was announced that the players were hospitalized and diagnosed with exertional rhabdomyolysis (Taylor, 2011a). The actual cause behind the diagnoses is still under investigation, but the common denominator for all the players who were diagnosed was participation in an extremely demanding exercise session. Rhabdomyolysis (pronounced rab-doe-my-ol-i-sis) is a muscle disorder in which muscle fibers break down and release myoglobin and muscle enzymes into the bloodstream, where they are then transported to the kidneys and eventually released into the urine (National Institutes of Health [NIH], 2011). A cascade of events commonly occurs, including depletion of adenosine triphosphate (ATP), impaired function of the sodium-potassium ATPase system, intracellular excess calcium accumulation, sarcolemma damage, and release of intracellular proteins and other substances into the blood (Patel, Gyamfi, & Torres, 2009). This syndrome has been shown to occur in normal, healthy individuals following strenuous exercise, and in this circumstance it is called “exertional rhabdomyolysis” (Harrelson, Fincher, & Robinson, 1995). Exertional rhabdomyolysis may lead to severe kidney stress, kidney failure, and even sudden death. Exertional rhabdomyolysis can occur in anyone: a recreational exerciser, a student in a physical education class, a dancer, an athlete on a sports team, or a member of the military. Basically anyone who does physical exercise at a level beyond their normal training routine is a potential candidate for exertional rhabdomyolysis. Exercise professionals have an obligation to understand the signs, symptoms, and treatment and prevention recommendations to ensure that those they supervise can exercise in a safe and effective manner.