The purpose of this study was to investigate the influence of 8° varus and vaigus shoe modifications on the foot mechanics in overground running. Twenty male subjects performed eight rearfoot running trials in three shoe conditions. Ground reaction forces, tibial accelerations, rearfoot motion, and in-shoe pressure distribution data were collected simultaneously. Between footwear conditions, force and acceleration parameters were found to be significantly different. Compared to the neutral shoe, maximum pronation and pronation velocity were reduced for the varus and increased for the vaigus shoes. Higher lateral rearfoot loads and an increased contribution of the first ray in the forefoot could be evaluated for the vaigus shoe. In contrast, a larger contribution of the medial midfoot and the fifth metatarsal head was observed for the varus shoe. The relative load analysis from the pressure distribution measurements provided additional information about the behavior of the foot in response to major changes in shoe construction.
Thomas L. Milani, Gerrit Schnabel and Ewald M. Hennig
Dana K. Voelker and Justine J. Reel
In this study, the authors examined female competitive figure skaters’ experiences of weight pressure in sport. Perceptions of the ideal skating body; sources of weight pressure; ways that body image, weight-management behaviors, and athletic performance have been affected; and recommendations for improving body image were explored. Aligning with a social constructivist view (Creswell, 2014), data were analyzed using an inductive thematic approach (Braun & Clarke, 2006). Skaters described the ideal skating body in an inflexible fashion with little room for deviation and acceptance of body diversity. Skaters cited their first weightpressure experience between 7 and 14 years of age, which most notably involved coaches, parents, skating partners, and other aspects of the skating culture. These experiences were characterized as promoting body-image concerns, unhealthy weight-management strategies, and interference with the psychological aspects of on-ice performance. Results from this study demonstrate the need to construct and maintain body-positive skating environments.
Denise M. Hill, Sheldon Hanton, Nic Matthews and Scott Fleming
The study examined the effect of an evidence-based intervention on choking in golf. It is informed by the work of Hill, Hanton, Matthews and Fleming (2010a) that explored the experiences of elite golfers who either choked or excelled under pressure. The perceptions of elite golf coaches who worked with both ‘chokers’ and those who excelled, were also considered. It revealed that choking may be alleviated through the use of process goals, cognitive restructuring, imagery, simulated training and a pre/postshot routine. The present study incorporated each strategy into an intervention that was introduced to two professional golfers (aged 22) who choked under pressure regularly. Through an action research framework the impact of the intervention was evaluated over a ten month period via qualitative methods. The results indicated the intervention alleviated the participants’ choking episodes and so provides information that can be of use to practitioners working with golfers who choke.
Leadership is often formalized within sport through captaincy, but researchers have yet to examine the realities of captaincy at the highest level of professional competition. The current study examined the benefits, pressures, and challenges of leadership and captaincy in the National Hockey League (NHL). One captain of an NHL team participated in two in-depth interviews, providing thorough descriptions of his first-hand experiences as an NHL captain, including (a) the techniques he uses to manage his media obligations, (b) his role as a communication bridge between players and coaches, (c) the composition of his leadership group, and (d) examples of interactions that occur during player-only meetings. The transition to captaincy was considered an especially challenging and pressure-filled period. Practical implications for sport psychology consultants are discussed in terms of how they can assist captains of elite competitive teams in setting realistic expectations for their leadership role.
Mark D. Geil
The sport of fencing involves asymmetric motions, large forces, and rapid changes in momentum. Today’s fencing shoes are designed to facilitate footwork but they provide little plantar force dissipation. Plantar foot pressures and kinematics were measured in 13 fencers. The study compared fencing shoes to a standard court shoe. The court shoe resulted in a significant reduction in plantar pressures during the fencing lunge, advance-lunge, and fleche. However, most fencers preferred the fencing shoe for fencing. The court shoe tended to alter fencing kinematics, generally though not significantly decreasing the velocity of the front foot and the weapon hand, and increasing the range of motion and overall travel of the weapon hand. This effect on fencing mechanics may stem from the design of the court shoe, or from an accommodation effect.
Heather M. Hayes, Joey C. Eisenmann, Kate A. Heelen, Greg J. Welk and Jared M. Tucker
The purpose of this study was to determine the joint association of fatness and physical activity on resting blood pressure in children. Subjects included 157 children (age 5.5–9.5 years). Moderate-to-vigorous physical activity (MVPA, min/day), body fatness, and resting blood pressure were measured. Four categories were created by cross tabulation of high/normal levels of fatness and high/low levels of MVPA. There were significant differences in systolic blood pressure and mean arterial pressure across the fat/MVPA groups (p < .05). Regardless of participating in an acceptable level of MVPA, overfat children had higher resting systolic blood pressure than normal fat children. MVPA did not significantly attenuate blood pressure within a fat category.
Stephen F. Burns, Hnin Hnin Oo and Anh Thanh Thuy Tran
The current study examined the effect of sprint interval exercise on postexercise oxygen consumption, respiratory-exchange ratio (RER), substrate oxidation, and blood pressure in adolescents. Participants were 10 normal-weight healthy youth (7 female), age 15–18 years. After overnight fasts, each participant undertook 2 trials in a random balanced order: (a) two 30-s bouts of sprint interval exercise on a cycle ergometer and (b) rested in the laboratory for an equivalent period. Timematched measurements of oxygen consumption, RER, and blood pressure were made 90 min into recovery, and substrate oxidation were calculated over the time period. Total postexercise oxygen uptake was significantly higher in the exercise than control trial over the 90 min (mean [SD]: control 20.0 [6.0] L, exercise 24.8 [9.8] L; p = .030). After exercise, RER was elevated above control but then fell rapidly and was lower than control 30–60 min postexercise, and fat oxidation was significantly higher in the exercise than control trial 45–60 min postexercise. However, total fat oxidation did not differ between trials (control 4.5 [2.5] g, exercise 5.4 [2.7] g; p = .247). Post hoc tests revealed that systolic blood pressure was significantly lower than in control at 90 min postexercise (control 104  mm Hg, exercise 99  mm Hg; p < .05). These data indicate that acute sprint interval exercise leads to short-term increases in oxygen uptake and reduced blood pressure in youth. The authors suggest that health outcomes in response to sprint interval training be examined in children.
Mark A. Sarzynski, Joey C. Eisenmann, Gregory J. Welk, Jared Tucker, Kim Glenn, Max Rothschild and Kate Heelan
The present study examined the association between the angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism, physical activity, and resting blood pressure (BP) in a sample of 132 children (48.4% female). Children attaining 60 min/day of moderate-to-vigorous physical activity (MVPA) possessed lower % body fat (29% vs 24%, p < .05). Resting BP did not significantly differ between genotypes. Furthermore, partial correlations between MVPA and BP were low and did not vary by ACE genotype. Thus, the ACE I/D genotype is not associated with BP and does not modify the relationship between physical activity and BP in this sample of children.
Joey C. Eisenman, Mark A. Sarzynski, Jerod Tucker and Kate A. Heelan
The purpose of this study was to examine if offspring physical activity may affect the relationship between maternal overweight and offspring fatness and blood pressure (BP). Subjects included 144 maternal-child pairs (n = 74 boys and 70 girls, mean age = 7.3 yrs). Maternal prepregnancy BMI was determined by self-report. Offspring characteristics included resting systolic and diastolic BP, body fatness by dual energy x-ray absorbtiometry, and moderate-to-vigorous physical activity (MVPA) using the Actigraph accelerometer. Children whose mothers were overweight or obese prepregnancy (Prepreg OW) were significantly larger and fatter than children from mothers with a normal prepregnancy BMI (Prepreg NORM). Prepreg OW children also had higher mean arterial pressure than Prepreg NORM children. BP values were not different across maternal Prepreg BMI/MVPA groups. Percent fat was significantly different across Prepreg BMI/MVPA groups. Prepreg OW children that did not meet the daily recommended value of MVPA were the fattest. Prepreg OW children that attained 360 min of MVPA/day had a mean percent body fat that was similar to Prepreg NORM children of either MVPA group.
Daniel A. Jacobs and Daniel P. Ferris
Instrumented insoles could benefit locomotion research on healthy and clinical populations by providing data in natural settings outside of the laboratory. We designed a low-cost, instrumented insole with 8 pneumatic bladders to measure localized plantar pressure information. We collected gait data during treadmill walking at 1.0 m/s and 1.5 m/s and for sit-to-stand and stand-tosit tasks for 10 subjects. We estimated a common representation of ground kinetics (3-component force vector, 2-component center of pressure position vector, and a single-component torque vector) from the insole data. We trained an intertask neural network for each component of the kinetic data. For the walking tasks at 1.0 m/s and 1.5 m/s, the normalized root mean square error was between 3.1% and 12.9% and for the sit-to-stand and stand-to-sit tasks, the normalized root mean square error was between 3.3% and 21.3% Our findings suggest that the proposed low-cost, instrumented insoles could provide useful data about movement kinetics during real-world activities.