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At least 19 recordsLinked to original sources
PubMed2001

Exacerbated physical fatigue and mental fatigue in Parkinson's disease.

OBJECTIVE: To characterize fatigue in Parkinson's disease (PD). BACKGROUND: Fatigue is a recognized problem in PD. Fatigue can be in the physical realm or in the mental realm. Fatigue has not been characterized in PD. METHODS: We characterized fatigue in 39 PD patients and 32 age-matched normal controls using five questionnaires: A. The Multidimensional Fatigue Inventory (MFI), which measures five dimensions of fatigue independently including general fatigue, physical fatigue, reduced motivation, reduced activity, and mental fatigue. B. The Fatigue Severity Inventory (FSI), which quantifies fatigue in general. C. The Profile of Mood States (POMS), which assesses six subjective subscales: tension-anxiety, depression-dejection, anger-hostility, fatigue-inertia, vigor-activity, and confusion-bewilderment. D. Center for Epidemiological Studies-Depression Scale (CES-D). E. Visual Analog linear scale of energy (VA-E). RESULTS: PD patients scored higher in all of the five dimensions of fatigue in the MFI including general fatigue, physical fatigue, reduced motivation, reduced activity, and mental fatigue (P < 0.001 except for mental fatigue P = 0.005). The severity of physical fatigue did not correlate with that of mental fatigue. PD patients scored higher on the FSI, POMS, CES-D, and scored lower on the VA-E. The scores in the FSI correlated with general fatigue, physical fatigue, reduced activity, and reduced motivation but not with mental fatigue in the MFI. Depression correlated with all dimensions of fatigue except physical fatigue in the MFI. Disease severity, as measured by Modified Hoehn and Yahr staging, did not correlate with any of the measures. CONCLUSIONS: PD patients have increased physical fatigue and mental fatigue compared to normals. Physical fatigue and mental fatigue are independent symptoms in PD that need to be assessed and treated separately.

Aged↗
PubMed2026

Catecholaminergic Contributions to Inhibitory Control Following Physical Fatigue: Behavioral and Neurophysiological Findings.

Acute physical fatigue can impair cognitive control, yet its underlying neurochemical mechanisms remain unclear. This study investigated whether catecholaminergic modulation influences behavioral and neural markers of inhibitory control following physical fatigue. Eighteen healthy, recreationally active adults (9 males, 9 females; 23.4&#xa0;&#xb1;&#xa0;2.2&#xa0;years) completed a randomized, triple-blind, placebo-controlled crossover study. On separate visits, participants received methylphenidate (MPH; 20&#xa0;mg; a dopamine and noradrenaline reuptake inhibitor), reboxetine (REB; 8&#xa0;mg; a noradrenaline reuptake inhibitor), or placebo. Physical fatigue was induced by repeated bilateral leg extensions to task failure. Cognitive performance was assessed before and after physical fatigue using a Go/No-Go task with electroencephalographic recording. Behavioral outcomes included reaction time and accuracy, while event-related potentials measured neural stages of response execution and inhibition (N2 and P3). Mixed-effects models were used for statistical analysis. For No-Go trials, a significant MPH&#xa0;&#xd7;&#xa0;Time interaction was observed for accuracy (p&#xa0;=&#xa0;0.008), with improved post-fatigue performance following MPH administration (p&#xa0;=&#xa0;0.048). At the neural level, MPH was associated with shorter fronto-central No-Go N2 latency (p&#xa0;=&#xa0;0.038) and altered fatigue-related changes in No-Go P3 latency (p&#xa0;=&#xa0;0.047). REB did not produce comparable behavioral or neural effects. These findings provide pharmacological evidence that catecholaminergic mechanisms contribute to inhibitory control following physical fatigue. The differential effects of MPH and REB suggest that selective noradrenergic enhancement alone is insufficient to maintain inhibitory control following physical fatigue. Instead, the findings implicate broader&#xa0;dopaminergic and noradrenergic mechanisms, potentially involving alterations in the temporal dynamics of inhibitory processing. TRIAL REGISTRATION: (G095422N and identifier NCT05880342).

Adult↗
PubMed2002

Quantification of cumulated physical fatigue at the workplace.

Quantification of physical fatigue remains a challenge. We hypothesized that its effects on central autonomic nervous system activity could be explored for such a quantification. To test this relationship, we prospectively measured central autonomic nervous activity through nocturnal heart rate variability (HRV) in six French garbage collectors, aged 32.1+/-4.3 years, twice a week during 3 consecutive weeks of work, and during the following week of rest. Eight healthy sedentary males formed a control group. HRV indices were calculated by applying standard temporal domain and wavelet transform analyses to standard ECG recordings. During the 3 consecutive weeks of work, there was a significantly progressive decrease in HRV indices, particularly pNN50 (-34.2%, P<0.05), as well as the high (-33.3%, P<0.05) and low (-22.2%, P<0.01) frequency components of wavelet transform, while there was an increase, although non-significant, of the ratio of low to high frequencies (9.1%). During the resting period, there was a significant recovery of HRV indices, notably of its high (50.0%, P<0.05) and low (28.6%, P<0.05) frequency components. No such changes occurred in the control group. A central signature of cumulated physical fatigue can thus be detected and quantified through nocturnal autonomic nervous system activity. Its characteristics are those of a progressive parasympathetic withdrawal.

Adult↗
PubMed2003

Levodopa improves physical fatigue in Parkinson's disease: a double-blind, placebo-controlled, crossover study.

We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation.

Aged↗
PubMed1997

Effects of exercise on fatigue, physical functioning, and emotional distress during radiation therapy for breast cancer.

PURPOSES/OBJECTIVES: To test the hypothesis that women participating in a walking exercise program during radiation therapy treatment for breast cancer would demonstrate more adaptive responses as evidenced by higher levels of physical functioning and lower levels of symptom intensity than women who did not participate. DESIGN: Experimental, two-group pretest, post-test. SETTING: Two university teaching hospital outpatient radiation therapy departments. SAMPLE: 46 women beginning a six-week program of radiation therapy for early stage breast cancer. METHODS: Following random assignment, subjects in the exercise group maintained an individualized, self-paced, home-based walking exercise program throughout treatment. The control group received usual care. Dependent variables were measured prior to and at the end of radiation therapy. In addition, symptoms were assessed at the end of three weeks of treatment. MAIN RESEARCH VARIABLES: Participation in the walking exercise program, physical functioning fatigue, emotional distress, and difficulty sleeping. FINDINGS: Hypothesis testing by multivariate analysis of covariance, with pretest scores as covariates, indicated significant differences between groups on outcome measures (p < 0.001). The exercise group scored significantly higher than the usual care group on physical functioning (p = 0.003) and symptom intensity, particularly fatigue, anxiety, and difficulty sleeping. Fatigue was the most frequent and intense subjective symptom reported. CONCLUSIONS: A self-paced, home-based walking exercise program can help manage symptoms and improve physical functioning during radiation therapy. IMPLICATIONS FOR NURSING PRACTICE: Nurse-prescribed and -monitored exercise is an effective, convenient, and low-cost self-care activity that reduces symptoms and facilitates adaptation to breast cancer diagnosis and treatment.

Adult↗
PubMed1985

Sleep deprivation, physical fatigue, and the perception of exercise intensity.

This paper presents the results of three experiments to determine the effect of sleep deprivation and physical fatigue on ratings of perceived exertion (RPE) for exercise of short (30 s) and long (15-50 min) duration. In the first, 12 male subjects walked on a treadmill, 50 min every 3 h, at 28% of their VO2max for 60 h without sleep. The RPE, recorded at the mid-point of each exercise bout, increased progressively with sleep loss. In the second experiment, when 12 female subjects performed ten 30-s bicycle exercise bouts before and after 54 h without sleep, there was no significant increase in RPE. In the third experiment, which examined the effect of physical fatigue on RPE, seven males performed two sets of ten 30-s bouts of cycle exercise before and after treadmill exercise at 70% of their VO2max to voluntary exhaustion. In one set, RPE was recorded; in the other, power output was measured. During the treadmill running, increases in RPE were observed and attributed to fatigue. This same fatigue caused only small changes in RPE and power output for the cycle exercise. The combined data suggest that where the exercise is of several minutes' duration, RPE is increased by sleep deprivation and by physical fatigue. Where the exercise period is as short as 30 s, sleep deprivation has no effect and physical fatigue causes only a small change in the perception of exercise intensity.

Adult↗
PubMed2000

Effect of Zena F-III, a liquid nutritive and tonic drug, on the neurochemical changes elicited by physical fatigue in mice.

The effects of a liquid nutritive and tonic drug (NTD) on the neurochemical changes elicited by physical fatigue in mice were investigated in terms of the calcium-dependent dopamine synthesizing function of the brain. In this study, Zena F-III (Taisho Pharmaceutical Co., Ltd., Japan), one of the most popular NTDs in Japan, containing 15 crude drug extracts together with taurine, caffeine, and vitamins, and formulated based on the precepts of traditional Chinese medicine, was used. Male mice were forced to walk for 0-6 h at a speed of 3 m/min using a programmed motor-driven wheel cage. The serum and brain calcium levels in the mice were significantly increased following forced walking. The increase in brain calcium level began later and was more gradual than that in the serum calcium level, and reached its maximum value following forced walking for 3 h. The neostriatal dopamine level was also significantly increased, and locomotor activity significantly decreased following forced walking for 3 h. Prior oral administration of F-III (10 ml/kg) attenuated the increases in the serum and brain calcium levels, the increase in the brain dopamine levels, and the decrease in locomotor activity induced by forced walking. Taking into consideration these findings with our previous reports, it is suggested that physical fatigue leads to an increase in dopamine synthesis in the brain through a calcium/calmodulin-dependent system, thereby inducing behavioral changes, and that F-III inhibits this pathway and may alleviate overwork-induced physical fatigue.

Animals↗
PubMed2004

Effects of physical fatigue in mice on learning performance in a water maze.

We investigated the effects of physical fatigue produced by swimming exercise on learning the Morris water maze in BALB/c mice. We measured the escape latency in the maze immediately after the swimming exercise. The control group was soaked in the water but not fatigued. For easier tasks, like one with an obvious cue flag, the escape latency was not changed by exercise fatigue. However, escape latency was increased after exercise fatigue for more difficult tasks of spatial learning. These results appear to suggest that physical fatigue impaired learning performance. The effects of swimming exercise fatigue on learning efficiency were then investigated. Mice were continuously fatigued during the spatial learning period. This increased escape latency between the first and third sessions. The results suggest that learning efficiency was impaired by exercise fatigue. This system may be useful for screening new foods used to enhance brain function during exercise.

Animals↗
PubMed2006

Aged garlic extract ameliorates physical fatigue.

Aged garlic extract (AGE) has recently received attention as a potent anti-fatigue agent. The principal aim of this study was to elucidate the mechanism responsible for the ameliorating effect of AGE on physical fatigue in rats caused by repeated endurance exercise on a mechanical treadmill apparatus. Rats were subjected to endurance exercise 5 times per week for 4 weeks. AGE at a dosage of 2.86 g/kg was administrated to rats 30 min before every exercise. Succinate dehydrogenase (SDH) activity in the gastrocnemius and soleus muscles and superoxide dismutase (SOD) activity, nitric oxide (NO) metabolites, and lactic acid concentration in plasma were evaluated as biomarkers of physical fatigue. SDH activity was increased 2-4-fold by repeated endurance exercise in comparison with unexercised (intact) rats, and AGE further up-regulated this activity by 40%. SOD activity was increased 5-fold, whereas AGE maintained it at a level equivalent to that in intact rats. Levels of NO metabolites were slightly decreased, whereas AGE enhanced them 2-fold. Lactic acid concentration was not changed in any of the groups. These results indicate that AGE may facilitate the turnover of aerobic glucose metabolism, attenuate oxidative stress, and promote oxygen supply based on vasodilation, suggesting that AGE ameliorates the various impairments associated with physical fatigue.

Animals↗
PubMed1978

Ergonomics. Reducing mental and physical fatigue in the dental operatory.

The work output and the mental and physical fatigue generated by a dental procedure is affected by the length and type of operation, physical facilities, the amount of cooperation given by the patient, operating techniques, and the effective teamwork and rapport of the operatory dental team. Fatigue is also generated by stresses that arise outside of the office and which, when superimposed over the normal operating stresses of the office, can have a cumulative effect of decreasing output and increasing mental and physical fatigue for the dentist, the assistant, and the patient. Probably the three most important means to compensate for both routine and nonroutine physical and mental stresses of any type or origin are: (1) learn to cope with or resolve the origin of the stress; (2) develop a pattern of healthy living; (3) cultivate job satisfaction.

Dental Assistants↗
PubMed1979

Effects of lifting frequency and technique on physical fatigue with special reference to psychophysical methodology and metabolic rate.

A laboratory study was conducted (1) to evaluate the effects of lifting frequency and technique on maximum acceptable work loads using psychophysical measurement technique, and (2) to compare the physiological fatigue criteria of 5 Kcal/min with the psychophysical fatigue criteria by measuring the metabolic rates at maximum acceptable work loads determined by subjective estimates of physical fatigue. Six male college students were required to lift from the floor to a 0.5 m height for 40 minutes. Four levels of lifting frequency (3, 6, 9 and 12 lifts/min) and three different lifting techniques (free sytle, stooped back and straight-back, bent-knee) were employed. Oxygen consumption rates were measured at maximum acceptable work loads (and were reduced to STPD). Statistical analysis showed that the maximum work loads acceptable to the workers were significantly affected by both lifting frequency and technique. Maximum acceptable work loads increased with an increase in lifting frequency. Both the subjective estimates of physical fatigue and the metabolic energy expenditure rate favored the free style lifting technique. The measured metabolic rates were in agreement with the physiological fatigue criteria of 5 Kcal/min only for six of the twelve combinations of lifting frequency and technique. Use of the physiological fatigue criteria will result in more liberal standards of work load at low work paces, especially for the stooped back and the free style lifting techniques.

Energy Metabolism↗
PubMed2003

In vitro training program to improve ambidextrous skill and reduce physical fatigue during laparoscopic surgery: preliminary experience.

PURPOSE: We illustrate the preliminary experience with our planned intensive in vitro training program focused on the nondominant hand and reducing physical fatigue. Apart from this, we tried to calculate how much training is required for a novice urologist to master laparoscopic freehand suturing with the dominant and nondominant hands. MATERIALS AND METHODS: Between December 2001 and May 2002, one trainee worked on a Pelvi-trainer, first with the dominant (right) hand and then with the left hand, practicing intracorporeal suturing and cutting and improving physical endurance by gradually increasing the duration of each training session. Along with the Pelvi-trainer, he worked on left-handed writing to improve wrist movements. Before starting this training, he did not have any laparoscopic experience as assistant or primary surgeon. The progress was stored in the computer prospectively to compare the results with those obtained at the end of the training. RESULTS: For the dominant hand, 30 hours over 2 months was required to master laparoscopic suturing skills. After training of the right hand, the nondominant hand required 40 hours of Pelvi-trainer work and 20 hours of handwriting during 2 months. Physical endurance for suturing in the Pelvi-trainer increased from 15 minutes to 150 minutes over 3 months. The main improvement was in the degree of pain over the right shoulder (because of the abducted position) and backache. CONCLUSION: Incorporation of sufficient in vitro training to improve nondominant hand functioning and reduce physical fatigue can make adaptation to laparoscopic surgery easier.

Clinical Competence↗
PubMed1978

Physical fatigue and the perception of differences in load: a signal detection approach.

Workload is an important factor related to perception of physical fatigue. Because a person engaged in physical activity eventually leading to painful exhaustion is in a pay-off situation, the paradigm of signal detection might be applicable to the perception of differences in load. Two male track and field athletes, aged 22 and 24 yr., participated in two experiments. In Exp. 1 difference threshold were determined with 25%, 50%, 60%, 65% and 70% of VO2 max as basic loads on a bicycle ergometer. Results showed a decreasing k over increasing work loads, contrary to Weber's law. In Exp. 2 a non-parametric signal detection procedure was used, with 25%, 40%, 50% and 60% of VO2 max as noise levels and a signal intensity of 1.5 watt in every condition. A chi 2 test for a 2-factor design showed only an effect of noise level. The converging results of both experiments led to the conclusion of a relative increasing sensitivity across increasing work loads. The main goal for future research will be to develop the signal detection method as a framework for research on fatigue.

Acoustic Stimulation↗
PubMed1998

Well-being, cerebral function, and physical fatigue after nocturnal hypoglycemia in IDDM.

OBJECTIVE: This study assessed the effect of nocturnal hypoglycemia on well-being cerebral function, and physical fatigue the next day in 10 subjects with IDDM. RESEARCH DESIGN AND METHODS: After an exercise test to determine work-loads corresponding to 30 and 60% VO2max, volunteers were studied twice, 4 weeks apart. Blood glucose was lowered one night to 2.3-2.7 mmol/l for 1 h, and at the control visit, hypoglycemia was avoided. The next morning, well-being was assessed using the minor symptom evaluation profile (MSEP), and cerebral function was assessed with the paced auditory serial addition test, the digit symbol substitution test, trail making part B, four-choice reaction time, and auditory P300 latency. Subjects then exercised at predetermined workloads corresponding to 30% VO2max for 30 min and 60% VO2max until exhaustion. Fatigue was assessed every 10 min using the Borg scale for rating of perceived exertion. RESULTS: All three components of the MSEP scored higher (indicating more symptoms) after the hypoglycemic night compared with the control night (P < 0.01 contentment, sleep; P < 0.001 vitality). None of the cerebral function tests performed the next day was affected by hypoglycemia. Exercise capacity was similar at both visits, but subjects were more fatigued after the hypoglycemic night (P < 0.01, analysis of variance). There were no differences in potassium, catecholamine, glucose, or lactate concentrations between visits either before or during exercise. CONCLUSIONS: One hour of hypoglycemia at night affects a subject's sense of well-being, but not cerebral function, the next day. The greater fatigue after the hypoglycemic night cannot be explained by the biochemical parameters measured.

Activities of Daily Living↗
PubMed1976

Specificity of training for motor skill under physical fatigue.

The purpose of the present study was to test the specificity of training principle from exercise physiology in the context of motor skill acquisition. Thirty-six college females were randomly assigned to either an experimental or a control group and both groups received 54 practice trials on a ladder climb task over four consecutive days (3,18,18 and 15 trials/day, respectively). The control group practiced under conditions of heavy interpolated fatigue on the first 3 days with day 3 representing the heavy-fatigue criterion conditions, while the experimental group did the same except for day 2 when a vowel-cancelling task was substituted for the fatigue task. On day 4 both groups practiced under the second criterion of non-fatigue conditions. Fatigue was induced by a step-up task so that a minimum HR of 180 beats/min was attained prior to each ladder trial. The results supported the specificity hypothesis that practicing a gross motor task under conditions of heavy-fatigue would facilitate performance of that task under criterion heavy-fatigue conditions. For the second criterion of non-fatigue practice, the data appeared to support the specificity principle but the rigorous test of the differences did not reach statistical significance. The overall evidence supports the position that regards heavy physical fatigue as a variable that can cause changes in the nature of certain motor skills so that the specificity of training principle becomes applicable.

Adult↗
PubMed1994

Physical fatigue in high and very high frequency manual materials handling: perceived exertion and physiological indicators.

This paper presents the results of a preliminary laboratory study undertaken to determine the perceived exertion and physiological responses of highly trained and experienced workers to high (up to 16 repetitions/min) and very high frequency (above 16 repetitions/min) manual lifting, lowering, and carrying/turning tasks. The results indicate that workers engaged in such highly repetitive and physically demanding tasks may operate at psychophysical workloads that may clearly be considered physically fatiguing and unacceptable according to the current physiological design criteria. In this study subjects performing lifting and lowering tasks, on the average, operated at 57% and 52% of their uphill treadmill aerobic capacity, respectively. For carrying and turning tasks, the average metabolic energy expenditure rate corresponded to 43% of subjects' aerobic capacity. The overall heart rates of the study subjects were 155 beats per minute (bpm) for lifting, 144 bpm for lowering, and 142 bpm for carrying and turning. These physiological responses, when compared with recommended physiological design criteria, are excessively high. The ratings of perceived exertion (RPE) for the shoulder, back, and whole body were highest for lifting (range, 10.20-15.50) and least for carrying and turning (range, 10.30-13.40; carrying and turning activities also included RPE of arms). Generally workers perceived the associated physical exertions as acceptable.

Adult↗