Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purposes of this study were to examine age and gender differences in knee extensor strength, power, and fatigue using open- and closed-chain testing procedures. We tested the hypothesis that specific strength (strength/unit muscle mass) would not differ by age, whereas age differences in specific power and fatigue would remain consequent to blunted maximal contractile velocity. Skeletal muscle performance was examined in 28 young (26.9 +/- 0.7 yr) and 24 older (63.6 +/- 0.8 yr) men and women. Assessments included one-repetition maximum strength for knee extension, leg press, and squat; concentric knee extensor peak power, velocity, and fatigability; and sit-to-stand power, fatigability, and relative neural activation (electromyograph activity during sit-to-stand movement normalized to electromyograph activity during isometric maximum voluntary contraction). Thigh lean mass (TLM; kg) was assessed by dual-energy X-ray absorptiometry. Specific strength (N/kg TLM) and specific power (W/kg TLM) were estimated by dividing absolute values by TLM. Age differences in specific strength were observed for knee extension only (young, 41.2 +/- 1.0 N/kg TLM; older, 32.4 +/- 1.0 N/kg TLM; P < 0.05). Adjustment for TLM did not negate age differences in knee extension specific power (25-41% lower in older; P < 0.05) across loads tested. Older adults experienced fatigue across 10 repetitions of knee extension as peak velocity fell by 24% (P < 0.05). Deficits in concentric power persist after adjustment for TLM as maximum contractile velocity falls markedly with aging. Older adults are less capable of sustaining maximum concentric velocity during repetitive contractions. These findings suggest that velocity impairments are a possible contributor to mobility loss and falls risk among older adults. Interventions for improving contractile velocity should be pursued.
 ...
PMID:Age differences in knee extension power, contractile velocity, and fatigability. 1534 25

Fatigue in the legs is a problem experienced by skiers. It has been suggested that optimal orthotics may reduce muscle fatigue for a given movement task by minimising muscle activity (Med. Sci. Sports Exerc. 31 (1999) S421). The aims were to determine whether EMG would provide an independent method of analysing myoelectric fatigue in the vastus lateralis (VL) during a skier's squat and whether orthotics could affect this fatigue response. Six skiers performed skier's squats for as long as possible with no orthotic, low volume orthotics and high volume orthotics in their ski boots. Bipolar, active surface electrodes recorded EMG activity in the VL throughout each squat. Results for the EMG median frequency showed a significant shift in the power density spectrum towards the lower frequencies (P < 0.05) at the end of the contraction, suggesting that myoelectric fatigue was occurring and was measurable using EMG. All conditions displayed a significant decrease in median frequency at the end of the contraction (P = 0.001). The high volume orthotic showed a significant reduction in myoelectric fatigue, however, there was no difference in the duration of squats across the three conditions (P > 0.05). Subjective and objective findings support the use of the high volume foot orthotic for skiers.
 ...
PMID:The effect of foot orthotics on myoelectric fatigue in the vastus lateralis during a simulated skier's squat. 1549 44

The development of the European total hip arthroplasty in the sixties of 20th century is associated mainly with the names of G. K. McKee, J. Charnley and M. E. Muller. The SICOT meeting in Paris in 1966 introduced THA as a new method of treatment of osteoarthritis of the hip and paved the way for the commercialization of the manufacturing of prostheses. The success of this method consisted primarily in the fixation of individual components by bone cement and application of metal-to-polyethylene and metal-to-metal joints. The book presents these historical events as they have been reflected in the development of THA in the countries of the former Czechoslovakia and in the development of implants of domestic provenance. The development of THA in the former Czechoslovakia started in 1969 and was based on the Swiss school established by M. E. Muller. The Muller component with the "banana-shaped" stem was implanted using the Watson-Jones approach, the proximal femur canal was prepared by a rasp and the Palacos cement was used. This prosthesis served also as the model for the first Czech implant Poldi-Cech of I generation (the Chirulen cup available in three sizes, the "banana- shaped" femoral component with a 32 mm head-diameter and 130 degree neck-shaft angle) the development of which started in 1969 and the serial production began in 1972 in the Poldi Kladno steel company. Fatigue fractures of the "banana-shaped" stem led to the development of the concept of a femoral component with an "anatomical" stem. In Switzerland, this concept was developed by B. G. Weber. In the former Czechoslovakia the development of a new femoral component with an "anatomical" stem following the shape of the intramedullary canal with an ovoid profile and without sharp edges started in 1972. Due to the incidence of fatigue fractures of the "banana-shaped"stem and material that was not sufficiently strong (steel used for the production of osteosynthetic components), 144 degree neck-shaft angle was chosen. Reduction of the effect of bending forces on the valgus stem had eliminated fatigue fractures. This Poldi-Cech prosthesis of II generation was provided in nine sizes. The diameter of the head remained the same. Three Chirulen cups were supplemented with a "flat" cup for implantation in a dysplastic acetabulum. The prosthesis was implanted with an exact instrument set (reamer for acetabular preparation, rasp for proximal femoral preparation, alignment device for accurate positioning of both the cup and the femoral component) with the use of the Palacos cement. The production of the Poldi-Cech prosthesis of II. generation started in 1974 with the fabrication of a monoblock. Since 1986 it has been developed into a modular system (14/16 cone) with the possibility to use a ceramic head of 32 mm diameter (only in the nineties the cone size was changed to 12/14 and the heads were provided also in the 28 mm diameter). The Poldi-Cech prosthesis of II generation with the "anatomical" stem has been implanted since 1974 (i. e. during 30 years) in more than 140 000 patients in the Czech and Slovak Republics. In the same year cemented monoblock hemiarthroplasty was developed on the same basis as THA using the same "anatomical" stem and 36 to 60mm head diameter. Until now more than 35,000 of these hemiarthroplasty systems have been implanted. Until 1992 the Poldi-Cech implant was practically the only available cemented total hip replacement in the former Czechoslovakia and retrospectively it may be considered a highly successful implant. In the authors' view, the further development of THA will lead in the following years to the use of implants proved by a long-term follow-up. Preference will be given to prostheses the implantation of which will require a minimal loss of the bone stock during primary surgery and which will allow a technically easy reimplantation. The continental Europe has been recently preferring hybrid prostheses while Scandinavia witnesses an evident increase in the number of implanted cemented prostheses to the detriment of the cementless and hybrid ones. Naturally, cementless prostheses will keep dominating in young patients.
 ...
PMID:The European school of total hip arthroplasty and 35 years of total hip arthroplasty in the Czech Republic. 1586 Jan 55

The aim of this study was to examine the effectiveness of Qi therapy (external Qigong) in the management of symptoms of advanced cancer in a man. We used a single case study design to evaluate the effectiveness of Qi therapy (external Qigong) in a 35-year-old man with advanced cancer (Stage IV) involving metastases in the stomach, lung and bone (Karnofsky performance scale: KPS, 40: requires special care and assistance, disabled). Treatment involved six days of pre-assessment, eight treatment sessions on alternate days over 16 days, and a two-week follow-up phase. A visual analogue scale (VAS) was used to assess the patient's self-reported symptoms of cancer over the intervention and follow-up periods. Following treatment, VAS scores' analysis revealed beneficial effects on pain, vomiting, dyspnoea, fatigue, anorexia, insomnia, daily activity and psychological calmness. These improvements were maintained over the two-week follow-up phase. After the first Qi therapy session, the patient discontinued medication and could sit by himself; after the fourth session, the patient was able to walk and use the toilet without assistance (improvement in KPS: 70: care for self, unable to perform normal activity or to do active work). Although limited by the single case study approach, our results support previous studies on this topic and provide reasons to conduct controlled clinical trials.
 ...
PMID:Effects of Qi therapy (external Qigong) on symptoms of advanced cancer: a single case study. 1627 68

Abdominal exercises are widely used to develop the anterior muscles of the trunk. These exercises can be undertaken without the aid of equipment, but increasingly manufacturers are developing equipment which purportedly enhances the training effect for abdominal muscles. As there are many different products and exercises used for abdominal muscle development, it is likely that some are more effective than others. This study aimed to investigate the effectiveness of five commonly performed abdominal exercises. A second aim was to investigate the effects of fatigue on these exercises. Five different types of abdominal exercise [standard crunch (sit-up) with bent knees, gym ball crunch, crunch with 5 kg weight held behind the head, legs raised crunch and a commercially manufactured roller crunch] were examined using integrated surface electromyography (IEMG). The lower rectus abdominis (LRA), upper rectus abdominis (URA) and obliquus externus abdominis (EO) of 15 healthy male participants [age (mean +/- SD) 22.2 +/- 6.8 years; height 1.77 +/- 0.06 m; mass 79.3 +/- 10.7 kg] were monitored using a four-channel special purpose EMG data logger. Three trials of each exercise were performed in random order and normalized to enable comparisons between muscles and exercises. At a later date, ten participants were then re-tested when fresh and after a 30 min whole-body fatigue protocol that specifically targeted the abdominal muscles. Two exercises were evaluated, the abdominal roller crunch and legs raised crunch, which were judged to be the least and most effective, respectively, of the five exercises previously used. The normalized IEMG showed significant (p < 0.001) differences between exercises (gym ball crunch = 86.0 +/- 7.5%; legs raised crunch = 79.9 +/- 5.1%; 5 kg weight crunch = 65.1 +/- 13.4%; standard crunch = 56.2 +/- 3.2%; and roller crunch = 45.0 +/- 11.4%). Post-fatigue, the normalized mean IEMG for both exercises increased significantly (p < 0.05) for LRA and URA muscles but not for the EO (p > 0.05). It was concluded that exercises can be constructed to provide a greater challenge to abdominal muscles, commercially available roller-type equipment appears to be little different from the standard abdominal crunch with bent knees, and fatiguing exercise results in the LRA and URA being more highly activated. These findings provide more detailed knowledge and understanding of the effects of different forms of abdominal exercise.
 ...
PMID:Electromyographic investigation of abdominal exercises and the effects of fatigue. 1633 26

The American College of Sports Medicine (ACSM) gives the following definition of health-related physical fitness: Physical fitness is defined as a set of attributes that people have or achieve that relates to the ability to perform physical activity. It is also characterized by (1) an ability to perform daily activities with vigor, and (2) a demonstration of traits and capacities that are associated with a low risk of premature development of hypokinetic diseases (e.g., those associated with physical inactivity). Information from an individual's health and medical records can be combined with information from physical fitness assessment to meet the specific health goals and rehabilitative needs of that individual. Attaining adequate informed consent from participants prior to exercise testing is mandatory because of ethical and legal considerations.A physical fitness assessment includes measures of body composition, cardiorespiratory endurance, muscular fitness, and musculoskeletal flexibility. The three common techniques for assessing body composition are hydrostatic weighing, and skinfold measurements, and anthropometric measurements. Cardiorespiratory endurance is a crucial component of physical fitness assessment because of its strong correlation with health and health risks. Maximal oxygen uptake (VO2max) is the traditionally accepted criterion for measuring cardiorespiratory endurance. Although maximal-effort tests must be used to measure VO2max, submaximal exercise can be used to estimate this value. Muscular fitness has historically been used to describe an individual's integrated status of muscular strength and muscular endurance. An individual's muscular strength is specific to a particular muscle or muscle group and refers to the maximal force (N or kg) that the muscle or muscle group can generate. Dynamic strength can be assessed by measuring the movement of an individual's body against an external load. Isokinetic testing may be performed by assessing the muscle tension generated throughout a range of motion at a constant angular velocity. The ability of a muscle group to perform repeated contractions over a specific period of time that is sufficient to cause fatigue is termed muscular endurance. Musculoskeletal flexibility evaluations focus on the joints and associated structures, ligaments, and muscles that cross the joints. The sit-and-reach test and the behind-the-back reach test satisfy many of the criteria for physical assessment of musculoskeletal flexibility. A physical fitness assessment must be integrated into all activities of daily living, as well as the physician's examination, to assess and promote health.
 ...
PMID:Physical fitness assessment: an update. 1670 Jun 60

The purpose of this pilot study was to assess the effects of a physical exercise program on physical performance and quality of life (QOL) in a population with incurable cancer and a short life expectancy. Thirty-four patients participated in a 50-minute group exercise program twice a week for 6 weeks. Physical performance was measured by three tests: "6-minute walk test," "timed repeated sit to stand," and "functional reach." Fatigue was measured by the Fatigue Questionnaire. QOL was assessed by the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire. The outcome variables were assessed before and after the intervention. The walk length increased and the "timed repeated sit to stand" was reduced (P < 0.05). Emotional functioning improved and physical fatigue was reduced (P < 0.05). Physical exercise seems to be a feasible way to improve well-being among patients with incurable cancer. Future randomized trials are needed to confirm the results.
 ...
PMID:The effect of a physical exercise program in palliative care: A phase II study. 1715 50

Pain and movement dysfunction are invariant sensory and motor expressions of health disorders. They are also complex, inter-related problems and may be accompanied by fatigue and depressed mood. Optimum management is predicated on the appropriate selection, application and interpretation of assessment measures. Research on pain and physical function using physical performance tests has shown that regardless of whether pain and impairment is a consequence of musculo-skeletal injury or systemic disease such as cancers, pain-free individuals outperform those with pain in terms of movement speed and endurance ability across a variety of performance tests (e.g. walk and reach tests, and repeated sit-to-stand and trunk flexion tests). Slow movements are characterized by fractionated and extraneous movement patterns. They are also associated with a relatively high level of muscle activity (amplitude and duration) throughout the task compared to fast movements. Slow movements are also relatively inefficient in terms of physiological energy and time burden. For a similar level of effort, individuals with pain are able to perform significantly less work. Our research has shown that individuals with pain move slower across a range of self-selected movement speeds i.e. slow, preferred and fast speeds. It is also apparent that patients systematically over estimate expected pain during task performance at faster speeds. Preliminary work using speed targeted treatment shows promise in terms of improving physical performance and reducing the burden of illness and physical dysfunction.
 ...
PMID:Measuring and managing pain and performance. 1687 Apr 88

Limited information exists concerning equitation as a viable form of physical activity. The study's purpose was to quantify effects of an equitation training program on health and physical fitness of college females. Following written informed consent, 15 college females enrolled in equitation and 10 controls (age = 23.6 +/- 2.5 years; ht = 165.3 +/- 5.3 cm; wt = 62.4 +/- 3.4 kg) underwent a comprehensive pre- and post-series of tests to assess cardiorespiratory response (Bruce; VO2(peak), HR(peak), VE(peak), RER(peak), MAP(peak), RPP(peak)), body composition (body mass, body fat, fat-free mass), muscular power [Wingate; peak and mean power (MP), total power output, fatigue index (FI)], muscular strength (curl-ups, reverse sit-ups, pushups, handgrip), blood chemistry, and coronary risk. The equitation group trained at various equine gaits for 14 weeks, 5 days/week. Multivariate analyses of variance (Wilks' Lambda) indicated a significant main effect of training across muscular power (F (4,25) = 3.965; P = 0.013), but not across cardiorespiratory response (F (11,18) = 1.472; P = 0.225), body composition (F (3,26) = 1.081; P = 0.375), or muscular strength (F (4,25) = 2.172; P = 0.102). Pre-post improvements in MP (+13.3%; P = 0.01), total work output (+11.8%; P = 0.015), and FI (-10.5%; P = 0.038) were observed. Nonsignificant improvements of 8.5-11.4% were observed in muscular strength and body composition. In conclusion, equitation does not provide an adequate stimulus to improve health and fitness in young adults. Individuals who participate in equitation need to supplement this activity with traditional aerobic and load-bearing training regimens.
 ...
PMID:Effect of equitation training on health and physical fitness of college females. 1689 31

The objective was to investigate perceptions of snowfield resort visitors about injury risk regarding alcohol, fatigue and recreational drug use. Visitors to a resort village in a large Australian snowfield region completed a brief survey about fatigue, alcohol and recreational drug use and injury risk perception. Participants stated their ability to ski or snowboard and drive safely following a lack of sleep, alcohol and recreational drug use. Intoxicated snowfield resort visitors were compared with non-intoxicated visitors. Safety beliefs across snow sport and transport were compared. Participants reported that they generally slept less than usual and 30% reported both drinking alcohol and using drugs more than usual while visiting the snowfields. Participants perceived driving as a greater injury risk than skiing/snowboarding (p < 0.001). Fatigue was perceived as a relatively weak injury risk factor, particularly whilst skiing and snowboarding. Awareness needs to be raised among snowfield resort visitors about the contribution of alcohol, fatigue and recreational drug use to snow sport and transport-related injury risk.
 ...
PMID:Drunk, drowsy, doped: skiers' and snowboarders' injury risk perceptions regarding alcohol, fatigue and recreational drug use. 1694 58


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>