Discrete pressure sensors were used to examine the influence of shoe construction on the local forces under the foot. Measurements were performed at eight locations under the feet of 22 subjects wearing 19 different models of running shoes. Mechanical properties of shoe soles were assessed with an impacter device. Pressure distribution, ground reaction force, and acceleration data were collected simultaneously during running at 3.3 m/s. Early lateral loading of the rearfoot was followed by increasing medial forefoot loads. In the later phase of pushoff the load was almost entirely carried by the first metatarsal head and the hallux. Substantial differences in plantar foot pressures and relative loads among shoe models indicated that footwear construction has a substantial influence on the loading behavior of the foot during ground contact. Finally, the chosen sensor locations under the foot were found to be adequate to estimate the vertical ground reaction force.
Ewald M. Hennig and Thomas L. Milani
Riann M. Palmieri, Christopher D. Ingersoll, Marcus B. Stone and B. Andrew Krause
To define the numerous center-of-pressure derivatives used in the assessment of postural control and discuss what value each might provide in the assessment of balance.
MEDLINE and SPORTDiscus were searched with the terms balance, postural control, postural sway, and center of pressure. The remaining citations were collected from references of similar papers. A total of 67 references were studied.
Understanding what is represented by each parameter used to assess postural control is crucial. At the present time the literature has failed to demonstrate how the variables reflect changes made by the postural-control system. Until it can be shown that the center of pressure and its derivatives actually reveal changes in the postural-control system, the value of using these measures to assess deficits in postural control is minimized.
Larry J. Weber, Thomas M. Sherman and Carmen Tegano
In this research, faculty reported attempts to influence their academic decisions regarding student athletes. In most instances the pressure was not formal or frequently applied, and it appeared to have little influence on faculty judgments or their willingness to assist athletes. Except for isolated situations of a flagrant nature that are sensationalized by the media, the problem seems not to be a major one.
Ewald M. Hennig and David J. Sanderson
Foot function and possible mechanisms for the etiology of frequently observed forefoot complaints in bicycling were studied. Pedal forces and in-shoe pressure distributions were measured with 29 subjects, who rode on a stationary bicycle with a cadence of 80 rpm at 100, 200, 300, and 400 W. The influence of footwear on foot loading was also investigated by comparing running and bicycling shoes at 400 W. The first metatarsal head and the hallux were identified as the major force-contributing structures of the foot. High pressures under the toes, midfoot, and under the heel showed that all foot areas contribute substantially to the generation of pedal forces. For increasing power outputs, higher peak pressures and relative loads under the medial forefoot were identified. These may cause pressure-related forefoot complaints and accompany increased foot pronation. As compared to the running shoe, the stiff bicycling shoe demonstrated a more evenly distributed load across the whole foot and showed a significantly increased index of effectiveness.
Jessica Hill, Glyn Howatson, Ken van Someren, David Gaze, Hayley Legg, Jack Lineham and Charles Pedlar
Compression garments are frequently used to facilitate recovery from strenuous exercise.
To identify the effects of 2 different grades of compression garment on recovery indices after strenuous exercise.
Forty-five recreationally active participants (n = 26 male and n = 19 female) completed an eccentric-exercise protocol consisting of 100 drop jumps, after which they were matched for body mass and randomly but equally assigned to a high-compression pressure (HI) group, a low-compression pressure (LOW) group, or a sham ultrasound group (SHAM). Participants in the HI and LOW groups wore the garments for 72 h postexercise; participants in the SHAM group received a single treatment of 10-min sham ultrasound. Measures of perceived muscle soreness, maximal voluntary contraction (MVC), countermovement-jump height (CMJ), creatine kinase (CK), C-reactive protein (CRP), and myoglobin (Mb) were assessed before the exercise protocol and again at 1, 24, 48, and 72 h postexercise. Data were analyzed using a repeated-measures ANOVA.
Recovery of MVC and CMJ was significantly improved with the HI compression garment (P < .05). A significant time-by-treatment interaction was also observed for jump height at 24 h postexercise (P < .05). No significant differences were observed for parameters of soreness and plasma CK, CRP, and Mb.
The pressures exerted by a compression garment affect recovery after exercise-induced muscle damage, with higher pressure improving recovery of muscle function.
Lacey Nordsiden, Bonnie L. Van Lunen, Martha L. Walker, Nelson Cortes, Maria Pasquale and James A. Onate
Many styles of foot pads are commonly applied to reduce immediate pain and pressure under the foot.
To examine the effect of 3 different foot pads on peak plantar pressure (PPP) and mean plantar pressure (MPP) under the first metatarsophalangeal joint (MTPJ) during slow running.
A 4 (pad) × 4 (mask) repeated-measures design.
University athletic training clinic and fitness facility.
20 physically active participants, 12 men (19.7 ± 1.3 y, 181.5 ± 6.3 cm, 83.6 ± 12.3 kg) and 8 women (20.8 ± 1.5 y, 172.7 ± 11.2 cm, 69.9 ± 14.2 kg) with navicular drop greater than or equal to 10 mm, no history of surgery to the lower extremity, and no history of pain or injury to the first MTPJ in the past 6 months.
PPP and MPP were evaluated under 4 areas of the foot: the rear foot, lateral forefoot, medial forefoot, and first MTPJ. Four pad conditions (no pad, metatarsal dome, U-shaped pad, and donut-shaped pad) were evaluated during slow running. All measurements were taken on a standardized treadmill using the Pedar in-shoe pressure-measurement system.
Main Outcome Measures:
PPP and MPP in 4 designated foot masks during slow running.
The metatarsal dome produced significant decreases in MPP (163.07 ± 49.46) and PPP (228.73 ± 63.41) when compared with no pad (P < .001). The U-shaped pad significantly decreased MPP (168.68 ± 50.26) when compared with no pad (P < .001). The donut-shaped pad increased PPP compared with no pad (P < .001).
The metatarsal dome was most effective in reducing both peak and mean plantar pressure. Other factors such as pad comfort, type of activity, and material availability must also be considered. Further research should be conducted on the applicability to other foot types and symptomatic subjects.
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.
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.
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.
Thomas L. Milani, Gerrit Schnabel and Ewald M. Hennig
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.