Search results for "Heel"
showing 10 items of 210 documents
Ski jumping boots limit effective take-off in ski jumping
2002
In this study, we measured the vertical and horizontal take-off forces, plantar pressures and activation patterns of four muscles (vastus lateralis, gluteus maximus, tibialis anterior, gastrocnemius) in 10 ski jumpers in simulated laboratory conditions when wearing either training shoes or ski jumping boots. We found significant differences in vertical (P < 0.001), horizontal (P < 0.05) and resultant (P < 0.001) take-off velocities and vertical force impulse (P < 0.01). We found no significant differences in the jumpers' initial take-off positions; however, the jumping boots condition resulted in a smaller displacement in the final position of the following joint angles: ankle angle (P < 0.…
Age-related variation in mobility independence among wheelchair users with spinal cord injury: A cross-sectional study
2016
To evaluate age-related variation in mobility independence among community-living wheelchair users with spinal cord injury (SCI).Community Survey (2011-2013) as part of the Swiss Spinal Cord Injury Cohort Study.Community.Individuals aged 16 years or older with traumatic or non-traumatic SCI permanently residing in Switzerland and using a wheelchair for moving around moderate distances (10-100 m).Not applicable.Mobility-related items of the Spinal Cord Independence Measure-Self Report were matched to the three principal domains "changing basic body position," "transferring oneself" and "moving around." Binary outcomes ("independence" vs. "no independence") were created for every domain and a…
Biomechanical loading in the triple jump
2000
The triple jump is a demanding field event in which a jumper must tolerate extremely high impact forces while maintaining high horizontal speed. The present study was designed to clarify the mechanical loading characteristics and the role of neuromuscular function in the triple jump. Seven national triple jumpers (4 males, 3 females) volunteered to perform 3-6 jumps. The mean best performances were 14.32+/-0.45 m and 11.90+/-0.28 m for males and females, respectively. The three longest triple jumps for each jumper were selected for final analysis. The mean contact times were 0.139 s (hop), 0.157 s (step) and 0.177 s (jump). The largest ground reaction forces were observed in the step (15.2 …
Withdrawal reflex organisation to electrical stimulation of the dorsal foot in humans.
2001
The present study investigated excitatory reflex receptive fields for various muscle reflex responses and reflex mediated ankle joint movements using randomised electrical stimulation of the dorsal and plantar surface of the foot in 12 healthy subjects. Eleven electrodes (0.5-cm2 cathodes) were mounted on the dorsal side and three on the plantar side of the foot. A low (1.5 times pain threshold) and a high (2.3 times pain threshold) stimulus intensity were used to elicit the reflexes. EMG signals were recorded from tibialis anterior (TA), gastrocnemius medialis (GM), soleus (SO), biceps femoris (BF), and rectus femoris (RF) muscles together with the ankle movement measured by a goniometer. …
Posterior tibial tendon dysfunction: Clinical and magnetic resonance imaging findings having histology as reference standard.
2017
Abstract Objective To investigate the correlation between MRI, clinical tests, histopathologic features of posterior tibial tendon (PTT) dysfunction in patients with acquired adult flatfoot deformity surgically treated with medializing calcaneal osteotomy and flexor digitorum longus tendon transposition. Materials and methods Nineteen patients (11 females; age: 46 ± 15 year, range 18–75) were pre-operatively evaluated using the single heel rise (HR) and the first metatarsal rise (FMR) sign tests. Two reviewers graded the PTT tears on a I–III scale and measured the hindfoot valgus angle on the pre-operative MRI of the ankle. The specimens of the removed portion of PTT were histologically ana…
Influence of age, gender and obesity on pressure discomfort threshold of the foot: A cross-sectional study
2021
[EN] Background: Foot pain is a highly prevalent health problem for which measures such as a pattern of Pressure Discomfort Threshold of the foot plantar surface can provide valuable information for orthosis design. This study aimed to describe such pattern as a tool for the assessment of painful conditions of the feet and to analyse how it modifies according to age, gender and obesity. Methods: A cross-sectional study was performed with participants allocated in: Group 1 people aged 20 to 35 years, Group 2 aged 50 to 65 years and Group 3 aged over 65. Pressure Discomfort Threshold on twelve points of the foot plantar surface was measured with an adapted manual dynamometer. Inferential anal…
Effects of whole-body vertical shock-type vibration on human ability for fine manual control
1991
The effects of vertical (z-axis) whole-body shock-type vibration on the ability for fine manual control were examined. The amplitudes and frequency of the shocks was varied, but a constant frequency-weighted acceleration of 1.25 m/s2 r.m.s. was maintained. The examination of the shock's effects was carried out using an experimental system that simulated the actual workplace of earth-moving machinery. Control was measured using a first-order pursuit tracking-test, in which a seated subject was asked to use both hands to direct a cursor on a monitor using a steering wheel. Although the magnitude of shocks (peak amplitude of 6-10 m/s2) and the number of shocks per unit time (shock cycle of 10-…
Validity and Test-Retest Reliability of the TIVRE-Basket Test for the Determination of Aerobic Power in Elite Male Basketball Players
2016
The aims of this study were to (a) determine the relationship between performance on the court-based TIVRE-Basket test and peak aerobic power determined from a criterion laboratory-based incremental treadmill test and (b) to examine the test-retest reliability of the TIVRE-Basket test in elite male basketball players. To address aim 1, 36 elite male basketball players (age: 25.2 ± 4.7 years, weight: 94.1 ± 11.4 kg, height: 195.83 ± 9.6 cm) completed a graded treadmill exercise test and the TIVRE-Basket within 72 hours. The mean distance recorded during the TIVRE-Basket test was 4001.8 ± 176.4 m, and mean VO2 peak was 54.7 ± 2.8 ml · kg(-1) · min(-1), and the correlation between the 2 parame…
Case study: effect of handrim diameter on performance in a paralympic wheelchair athlete.
2009
This study, with a top T-52 class athlete, determines the relationship between stroke frequency (SF) and push time (PT) and wheelchair velocity (Wv) using different handrim diameters (HD) and the effect of different HDs on the athlete’s heart rate (HR) and blood lactate (LACT) at competition speeds. Wv shows a linear-direct relationship with SF but a linear-inverse relationship with PT (p < .001 in both cases). Using bigger handrims (0.37 m instead of 0.36 m), SF increases 6%, while PT decreases 27% (at 24 Km·h–1). HR (p < .0001) increases with Wv and is also affected by HD with differences between the 0.34 m—0.36 m handrim group (lower values) and the 0.37 m handrim (higher values). …
Achilles tendon ultrasonography may detect early features of psoriatic arthropathy in patients with cutaneous psoriasis.
2014
SummaryBackground Psoriatic arthropathy is a progressive and debilitating disease involving reduction of functional activity of the articulations with consequent deterioration of the patient's quality of life. The entheses represent the initial site of articular inflammation and the enthesis of the Achilles tendon is the first to be affected. In some patients with psoriasis, enthesitis may not be diagnosed because it is still asymptomatic. Objectives To evaluate whether ultrasonography allows early diagnosis in a larger population and to identify significant alterations of enthesitis beyond increased thickness of the Achilles tendon. Materials and methods The study was undertaken on 59 pati…