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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Trans-tibial amputees are advised to walk as much as able people to achieve healthy and independent life. However, they usually have difficulties in doing so. Previous researches only included data from a few steps when studying the gait of amputees. Walking over a long distance was rarely examined. The objective of this study was to investigate the changes in spatial-temporal, kinetic and kinematic gait parameters of trans-tibial amputees after long-distance walking. Six male unilateral trans-tibial amputees performed two sessions of 30-min walking on a level treadmill at their self-selected comfortable speed. Gait analysis was undertaken over-ground: (1) before walking, (2) after the 1st walking session and (3) after the 2nd walking session. After the long-distance walking, changes in spatial-temporal gait parameters were small and insignificant. However, the sound side ankle rocker progression and push-off were significantly reduced. This was due to the fatigue of the sound side plantar flexors and was compensated by the greater effort in the prosthetic side. The prosthetic side knee joint showed significantly increased flexion and moment during loading response to facilitate the anterior rotation of the prosthetic shank. The prosthetic side hip extensors also provided more power at terminal stance to facilitate propulsion. Endurance training of the sound side plantar flexors, and improvements in the prosthetic design to assist anterior rotation of the prosthetic shank should improve long-distance walking in trans-tibial amputees.
Gait Posture 2012 Feb
PMID:Long-distance walking effects on trans-tibial amputees compensatory gait patterns and implications on prosthetic designs and training. 2205 54

The aim of this study was to evaluate the changes in electromyographic (EMG) activity of the lower limb muscles, and hip, knee and ankle kinematics during gait while wearing low- (4-cm) and high-heeled (10-cm) shoes in 31 young and 15 middle-aged adult women. We observed an increase in knee flexion and decrease in ankle eversion associated with elevated heel heights suggesting that compensatory mechanisms attenuating ground reaction forces may be compromised during gait with higher-heeled shoes. Additionally, we observed increased muscle activity during high-heeled gait that may exacerbate muscle fatigue. Collectively, these findings suggest that permanent wearing of heeled footwear could contribute to muscle overuse and repetitive strain injuries.
Gait Posture 2012 Apr
PMID:The influence of heel height on lower extremity kinematics and leg muscle activity during gait in young and middle-aged women. 2230 Jul 29

The uncontrolled manifold (UCM) analysis has been demonstrated to be a powerful tool for understanding motor variability. The purpose of this study was to use the UCM analysis to investigate the effects of load carriage and fatigue on gait variability. Whole-body kinematic data during treadmill walking were collected from 12 healthy male participants when fatigue and load carriage were applied. The task-level variable for the UCM analysis was selected to be the whole-body COM. We chose to analyze the whole-body COM data at two important gait events: right heel contact and right toe off, and the UCM analysis was carried out in the sagittal and frontal planes, separately. The dependent measures were UCM variability measures and UCM ratio. Three-way ANOVA was performed to determine the main and interaction effects of back-carrying load, fatigue, and gait events on the dependent measures. The results showed that frontal UCM ratio significantly changed with the application of back-carrying load and fatigue, indicating that both factors had effects on motor performance in stabilizing the whole-body COM in the frontal plane. These findings can facilitate a better understanding of the nature of motor variability due to load carriage and fatigue.
Gait Posture 2012 Jun
PMID:Uncontrolled manifold analysis of gait variability: effects of load carriage and fatigue. 2246 38

The present study investigated the effects of somatosensory conditions at the foot and ankle on postural responses to plantar-flexor muscle fatigue during bipedal quiet stance. Twenty-two young healthy adults were asked to stand upright as still as possible with their eyes closed in three somatosensory conditions (normal, altered and improved) both prior to and after exercises inducing plantar-flexor muscle fatigue. In the normal condition, the postural task was executed on a firm support surface constituted by the force platform. In the altered condition, a 2-cm thick foam support surface was placed under the subjects' feet. In the improved condition, increased cutaneous feedback at the foot and ankle was provided by strips of athletic tape applied across both their ankle joints. Muscle fatigue was induced in the plantar-flexor muscles of both legs through the execution of a repeated standing heel raise exercise. Centre of foot pressure displacements were recorded using a force platform. Results showed that plantar-flexor muscle fatigue yielded increased centre of foot pressure displacements under normal foot and ankle sensory conditions. Furthermore, this effect was exacerbated under altered foot and ankle sensory conditions and mitigated under improved foot and ankle sensory conditions. Altogether, the present findings suggested an increased reliance on somatosensory information from the foot and ankle for controlling upright posture in the presence of plantar-flexor muscle fatigue.
Gait Posture 2012 May
PMID:Do somatosensory conditions from the foot and ankle affect postural responses to plantar-flexor muscles fatigue during bipedal quiet stance? 2246 4

Back pain resolution has not statistically improved over many years with some literature suggesting chronic back pain to be increasing. From a search of literature on causes, events, mechanisms, factors and treatment for back pain, a model is developed that relates causes of back injury to factors that result in pain through two primary mechanisms; muscle fatigue and muscle/tendon/connective tissue strain or sprain with other main mechanisms being diminished reactivity and strength, changes in tendon/tissue mechanical properties and fear of back pain recurrence/fear of movement following a back pain episode. The model highlights the fact that back pain/injury is multi-factorial with numerous circular relationships. Therefore treatment should also be multi-factorial; a combination of physical and psychological therapy with attention to mechanisms at work or in daily living that exacerbate the injury and delay recovery thereof. Exercise is one method that can reduce muscle imbalance, improve resilience to muscle fatigue, and address reactivity and strength. More importantly, eccentric exercise can rectify musculotendinous or connective tissue injury which plays a role in prolonging the back injury cycle. Posture is identified as a causative factor for back pain with the time exposure for posture representing the largest portion of daily activities. From literature and from clinical observation, treatment methods can be improved and incorporated into integrated multi-modal programs. An integrated exercise program that commences with motor control exercise and progresses into functional movement is suggested. Furthermore a modification of the McKenzie extension movement may benefit back injury rehabilitation for a majority of lower back pain patients. Otherwise the sit-to-stand movement is a regular and frequent exacerbating mechanism of back pain and likely continuously tears connective tissue during the movement thus prolonging the cycle of back pain and can be addressed instantly with a modification in sit-to-stand technique.
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PMID:Multi-factorial causative model for back pain management; relating causative factors and mechanisms to injury presentations and designing time- and cost effective treatment thereof. 2265 16

Walking deterioration occurs frequently in adults with spastic bilateral cerebral palsy (CP), but their gait characteristics are largely unknown. The study aims were (1) to compare selected gait analysis variables between those reporting and those not reporting walking deterioration, and (2) to characterise the overall gait deviations and classify the gait patterns. Participants (N=16) were recruited from a follow-up study, had spastic bilateral CP, <40 years in 2006, GMFCS levels I-III, and could walk at least 10 m without support. Eight reported walking deterioration (cases) and eight did not (controls). A theoretical framework linking work of walking, fatigue and deterioration in walking was developed. It was hypothesised that higher energy requirements during gait and larger gait deviations would be associated with deterioration in walking. Three-dimensional gait analysis was used to obtain centre of mass work, mechanical joint work, lower limb kinematics, movement analysis profile (MAP), and gait profile scores (GPS). There were no differences between the cases and controls in centre of mass work, joint work, or in the GPS. The largest MAP deviations were seen in sagittal pelvis, hip, and knee angles and foot progression. Crouch and asymmetric gait were common patterns. Walking deterioration could not be explained by these work and kinematic variables. An individual's perception of deterioration in walking is subjective, and may be experienced and interpreted differently across people. Larger, longitudinal studies on the natural history of walking in spastic CP are needed. Qualitative studies on the subjective experiences of walking deterioration are also warranted.
Gait Posture 2013 Feb
PMID:Walking deterioration and gait analysis in adults with spastic bilateral cerebral palsy. 2281 16

Prolonged standing in an occupational setting has long been associated with the development of low back pain. In response to this, researchers have investigated various interventions that can alleviate low back pain and discomfort, such as anti-fatigue mats, shoe insoles, and more recently, sloped platforms. The purpose of this study was to investigate the effects of a sloped surface on kinematics and trunk muscle thickness during quiet and prolonged occupational standing. Eleven participants performed 1-min quiet standing tasks on three surfaces - level ground, incline, and decline - followed by 16-min of prolonged standing in each condition. Trunk, lumbar, and global pelvis angles were measured during each standing condition, and muscle thickness measurements of erector spinae and the lateral abdominal wall were taken during the quiet standing task. During quiet standing, there were systematic changes in trunk, lumbar, and pelvis angles with the different surfaces; however, these changes were not accompanied by systematic changes in muscle thickness. The responses found during the quiet standing were consistent during prolonged standing. As a result, the reduced perceived low back pain found when using sloped platforms is likely not the result of changes in morphology of the trunk musculature, but might be related to the altered kinematics caused by standing on these platforms.
Gait Posture 2013 Mar
PMID:Possible mechanisms for the reduction of low back pain associated with standing on a sloped surface. 2288 60

The aim was to examine the effects of muscle fatigue of knee extensor and hip abductor muscles on dynamic standing balance of patients with patellofemoral pain syndrome (PFPS) compared to their healthy matched controls. Thirty participants (15 with PFPS, 15 controls) were recruited. Isolated muscle fatigue of two muscles was induced isokinetically in three separate sessions (one practice and two testing sessions) with a rest interval of at least 72h. In each testing session, fatigue protocol of only one muscle group was performed for the both legs with a rest time of 30min. After determining peak torque, participants were encouraged to perform continuous maximal concentric-eccentric contraction of the target muscle until the torque output dropped below 50% of peak value for 3 consecutive repetitions. Immediately after the completion of the fatigue protocol, balance testing of participants was undertaken during single leg standing using the Biodex stability system. Balance stability measures included the overall, anteroposterior and mediolateral stability indices (OSI, APSI and MLSI, respectively). Patients exhibited decreased balance stability in the sagittal plane (higher APSI) when compared to controls. Isolated muscle fatigue of the knee extensors and hip abductors reduced balance stability in both study groups. Fatigue of hip abductors was associated with greater balance instability (higher OSI and APSI) than fatigue of knee extensors.
Gait Posture 2013 Mar
PMID:The effects of muscle fatigue on dynamic standing balance in people with and without patellofemoral pain syndrome. 2294 99

Tripping over obstacles is a common cause of falls in older adults, and muscle fatigue, which can alter walking patterns, may add to this risk. To date, no study has examined the effect of lower limb muscle fatigue on obstacle negotiation in older adults. 30 older adults (13 women, aged 78.3 [6.2] years) negotiated a 12 m obstacle course, while completing a visual secondary task, under two randomized conditions: rested or fatigued. For the fatigue condition, participants performed a repeated sit-to-stand movement, as fast as possible, until they could no longer continue. Participants then immediately began walking trials. Kinematic and kinetic data were collected on approach to, during, and after crossing a height-adjustable target obstacle (10% and 20% of leg length). Repeated measures ANOVA showed a statistically significant increase in lead limb vertical loading rate after stepping over the 10% obstacle when fatigued, relative to rested (P=0.046). No other significant between-condition differences (>0.05) were observed for the other kinematic variables when negotiating the 10% obstacle. Furthermore, no significant between-condition differences (P>0.05) were observed for any kinetic or kinematic variables when negotiating the 20% obstacle. This study describes a feasible method for investigating the consequences of lower limb muscle fatigue on obstacle crossing. The current finding of increased vertical loading rate when fatigued supports the need for further investigation into the effect of muscle fatigue on gait under different environmental conditions, fatiguing a range of muscles, analyzing a more comprehensive array of kinetic and kinematic measures, and in healthy and clinical populations.
Gait Posture 2013 Apr
PMID:The effect of lower limb muscle fatigue on obstacle negotiation during walking in older adults. 2302 90

The stride before landing may be important during stepping down. The aim of this study was to analyze variability of the kinematics and muscle activity in the final stride before stepping down a curb, with and without ankle and knee muscle fatigue. Ten young participants walked at self-selected speed and stepped down a height difference (10-cm) in ongoing gait. Five trials were performed before and after a muscle fatigue protocol (one day: ankle muscle fatigue, another day: knee muscle fatigue). The analysis focused on the trailing leg during the last but one and the last step on the higher level. Kinematics and muscle activity were recorded. Fatigue increased variability of foot-step horizontal distance in the last step on the higher level of the trailing limb, as well as in the first steps on the lower level for both limbs. This appeared due to an increase in the range of motion of the knee joint after both fatigue protocols. Participants additionally showed an increased ankle and hip ROM and decreased knee ROM. Our results suggest a loss of control under fatigue reflected in a higher variability of trailing and leading limb-step horizontal distances, with compensatory changes to limit fatigue effects, such as a redistribution of movement over joints.
Gait Posture 2013 Apr
PMID:The effect of muscle fatigue on the last stride before stepping down a curb. 2306 31


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