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COORDINATION VARIABILITY IN OVERGROUND RUNNING AND WALKING AT PREFERRED AND FIXED SPEEDS
Get PDFCoordination variability (CoordV) is impacted by the type and speed of locomotion, however, the appropriate number of trials required for stable outputs during overground locomotion is yet to be determined. The purpose of this study was to analyse the CoordV of lower limb segment and joint couplings to determine the number of trials needed for a stable mean during running and walking at preferred and fixed speeds. Three-dimensional lower-limb kinematics were captured for recreational runners (n = 10) performing 20 trials of each condition. Using a modified vector coding technique, segment and joint couplings were derived, from which, CoordV was calculated using circular statistics. The number of trials required to achieve a mean within 100±10% of a 20 stride mean was determined for each individual. The study findings indicate the need for between 8 and 9 trials to produce a stable mean and contribute to reliable biomechanical outputs
LOWER LIMB KINEMATICS OF CHILDREN JUMPING ON DOMESTIC TRAMPOLINES
Get PDFDomestic trampolines are a globally popular recreational activity for children, however this comes with a potentially increased risk of lower limb strains. The aim of this research was to determine if trampolines of differing stiffness influence lower limb kinematics in children. Fourteen participants grouped based on age; 5-7 and 9-11 years old, each performed twenty bounces on three different trampolines of varying stiffness. Lower limb kinematics were analysed across the ten middle bounces for each trampoline. Findings demonstrated no significant interaction effects across any hip, knee, ankle or foot kinematic variables across the trampolines within both age groups. There were also no significant differences in performance variables across the three trampolines. This study suggests that children do not appear to alter lower limb kinematics in adapting to different trampoline stiffness\u27s
AUTOMATED MULTI-FEATURE SEGMENTATION OF TREADMILL RUNNING
Get PDFThe definition of gait events and phases have been well established in the literature through the use of qualitative movement descriptors. The repeatable, objective definitions of gait events and phases is the cornersone of sucess when performin a multi-center trial. A correlation-based multi-feature automated segmentation algorithm was developed and applied to treadmill running data. The features used were soley from 3D kinematic marker trajectory data, including generated features such as vectors between kinematic markers. The algorithm was compared against a trained tester who used visual inspection and threshold limits of the vGRF to segment stance. The automated segmentation approach was shown to consistently identify the same gait events as the trained tester, representing a significant time savings for the signal processing of large volume treadmill running data
TO DO OR NOT TO DO; INVESTIGATING THE EFFECTS OF POSITIVE AND NEGATIVE VIDEO INSTRUCTIONS ON SIDE-STEP CUTTING
Get PDFThe purpose of this study was to examine the effects of positive and negative instructions on knee joint loading. Eighteen basketball players performed sidestep cut exercises with positive (optimal knee joint loading) and negative (suboptimal knee joint loading) visual instructions given by videos of experts performing side-step cutting. The results showed that subjects performed not significantly different compared to experts in the positive condition.The reduced knee joint loading seemed to indicate that subjects were able to imitate the experts to some extent. However, there was a significant difference between the negative condition of subjects and experts. This finding suggest that subjects could not completely copy the negative movements of the experts. Therefore, this might implicate that coaches should use experienced athletes as experts when demonstrating exercises to promote the highest learning effect
FOOTFALL PATTERN DURING RUNNING IN PRESCHOOL CHILDREN ACCORDING TO AGE AND FOOTWEAR
Get PDFThe aim of this study was to compare the footfall pattern (FP) in different age groups of preschool children while they ran in standard running shoes (SRS) and barefoot. Forty-eight children aged 3-6 years participated in the study and were split into 4 age groups (n=12). All children performed a simple running game (based on the shuffle run) in SRS and barefoot. The length of the runway was adjusted for each age group. Kinematic and kinetic data were collected using 3-D motion capture system. We analyzed strike index (SI) and sagittal plane ankle angle (AA) at initial contact (IC) from 6 successful running trials for each child in each condition. We found differences between conditions in both SI (p=0.000, η2=0.448) and AA (p=0.000, η2=0.259) respectively, but we did not find any differences among age groups. Moreover, we found an interaction between age and conditions in AA (p=0.019, η2= 0.201). In preschool children, FP changed differently in certain age groups according to the footwear condition
EVALUATING THE EFFECTS OF ACCEPTANCE AND COMMITMENT TRAINING ON BURNOUT IN BEHAVIOR TECHNICIANS WORKING IN MENTAL HEALTH FACILITIES
No full textBurnout in the workplace has been a predominant concern, long before the 1970s, when the issue of burnout became more mainstream to the general public. Subsequently, burnout within the human services occupation had fallen victim to the growing movement, which was plaguing the world due to the long and grueling hours, dealing with patients/clients’ undesirable demands and complaints, and the lack of resources within the facilities. These issues lead to the three dimensions created by burnout; exhaustion, cynicism, and inefficacy among health care workers. Until 30-40 years ago, the only research conducted on burnout was focused on prevention strategies. However, there was a paucity of research on the use of reduction strategies to decrease burnout especially in the highly susceptible fields, which include mental health workers. Acceptance and Commitment Training (ACT) is a behavioral therapy approach aimed at increasing psychological flexibility and encourages people to experience life in the present moment. One of the many goals is to decrease the need to analyze or contemplate one’s past or the future. This study utilized a nonconcurrent multiple baseline across participants design to evaluate the effectiveness of treatment by focusing on creating values-directed behaviors. Practical increases in values-directed behaviors among the four mental health workers were observed. Positive gains continued to increase throughout the progression of the study. Exploratory data suggested a possible decrease in job-related tension and a possible increase in self-compassion
UNDIAGNOSED MOVEMENT DISORDER IN SPEED SKATING: A POSSIBLE FORM OF TASK SPECIFIC DYSTONIA
Get PDFThis study aimed to investigate the bio-mechanics of a mysterious and undiagnosed movement disorder appearing in the Netherlands among expert speed skaters known as ‘zwabbervoet’ or, skater’s cramp. An unpublished manuscript looking at 5 affected skaters indicates that the disorder may be a form of task specific dystonia. Using a novel tailor-made program for analyzing speed skating, this study looked at the kinematic features of skater’s cramp. The results showed skater’s cramp was person specific, that it had a clear, consistent asymmetry that was predictable across multiple gait cycles irrespective of speed or intensity of skating. A more in depth analysis combining electromyography and force measurement with the current analysis is in development to further investigate the task specificity of this disorder
INFLUENCE OF FOOTWEAR AND BREAST SUPPORT ON THE TRUNK MOVEMENTS DURING RUNNING
Get PDFThe purpose of the study was to analyze the influence of footwears and breast supports on the spine movements during running. Seventeen women performed a treadmill run using different combinations of footwear (barefoot, minimalist and traditional) and breast support (bare breast, everyday bra and sports bra). Spine movements were registered using optoelectronic cameras that recorded reflective markers fixed from the cervical to the sacral regions. From the 3D coordinates of the markers, the geometric curvatures of the spine were calculated in the sagittal plane at each instant of time in the gait cycle, as well as the neutral curve (mean posture of the spine). Results showed that the sports bra and footwear caused greater curvatures in the thoracic and lumbar regions, respectively, suggesting that women change their posture depending on the sportswear used
INTER TREADMILL VARIATION IN BELT VELOCITY REGULATION
Get PDFThe purpose of the present study was to develop a novel method to quantify instantaneous belt velocity and to investigate differences in belt velocity regulation between different types of treadmills. We used circular cut-outs of reflective tape attached to the lateral aspects of the treadmill to determine its instantaneous belt velocity. By testing three treadmills with seven participants we were able to identify clearly different instantaneous belt velocity patterns between treadmills. Peak deviation amplitudes correlated positively with the body mass of runners, even though the slope of this relationship was different between treadmills for positive deviations from target speed. These results highlight the importance of considering belt velocity regulation differences in human locomotion studies and treadmill training
COMPARISON OF KINEMATICS ON 30 M SPRINTS WITH 0, 10, 20, 30 AND 40% BODY WEIGHT OF ACTIVE RESISTANCE IN EXPERIENCED SPRINTERS
Get PDFThe purpose of this study was to compare kinematics of un-resisted and active resisted 30m sprints with different loads in experienced sprinters. kinematics were measured using laser gun, contact mat and IMUs integrated with a 3-axis gyroscope in fourteen participants during an un-resisted 30 m sprint and sprints with a 10, 20, 30 and 40% of body weight (BW) active resistance. The main findings were that 30m times increased with resp. 16, 31, 51 and 77% from 3.95±0.28 (un-resisted) to 6.99 ±0.85 s (40% BW resistance). These increases were caused by lower maximal velocity reached earlier in the 30m sprints. The lower maximal velocity was a result of shorter step length, flight time and longer contact times. These changes were accompanied with lower maximal knee and hip extension, and plantar flexion velocities with increasing resistance