Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression

Abstract:

OBJECTIVES: Patients with chronic fatigue syndrome complain of physical and mental fatigue that is worsened by exertion. It was predicted that the cognitive and motor responses to vigorous exercise in patients with chronic fatigue syndrome would differ from those in depressed and healthy controls.

METHODS: Ten patients with chronic fatigue syndrome, 10 with depressive illness, and 10 healthy controls completed cognitive and muscle strength testing before and after a treadmill exercise test. Measures of cardiovascular functioning and perceived effort, fatigue, and mood were taken during each stage of testing.

RESULTS: Depressed patients performed worst on cognitive tests at baseline. During the treadmill test, patients with chronic fatigue syndrome had higher ratings of perceived effort and fatigue than both control groups, whereas patients with depression reported lower mood. After exertion, patients with chronic fatigue syndrome showed a greater decrease than healthy controls on everyday tests of focused (p=0.02) and sustained (p=0.001) attention, as well as greater deterioration than depressed patients on the focused attention task (p=0.03). No between group differences were found in cardiovascular or symptom measures taken during the cognitive testing.

CONCLUSIONS: Patients with chronic fatigue syndrome show a specific sensitivity to the effects of exertion on effortful cognitive functioning. This occurs despite subjective and objective evidence of effort allocation in chronic fatigue syndrome, suggesting that patients have reduced working memory capacity, or a greater demand to monitor cognitive processes, or both. Further insight into the pathophysiology of the core complaints in chronic fatigue syndrome is likely to be realised by studying the effects of exercise on other aspects of everyday functioning.

 

Source: Blackwood SK, MacHale SM, Power MJ, Goodwin GM, Lawrie SM. Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression. J Neurol Neurosurg Psychiatry. 1998 Oct;65(4):541-6. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2170292/ (Full study)

 

The case history of an elite ultra-endurance cyclist who developed chronic fatigue syndrome

Abstract:

An elite ultra-endurance athlete, who had previously undergone physiological and performance testing, developed chronic fatigue syndrome (CFS).

An incremental cycling exercise test conducted while he was suffering from CFS indicated decreases in maximum workload achieved (Wmax; -11.3%), the maximum oxygen uptake (VO2max; -12.5%), and the anaerobic threshold (AT; -14.3%) compared to pre-CFS data.

A third test conducted after the athlete had shown indications of significant improvement in his clinical condition revealed further decreases in Wmax (-7.9%), VO2max (-10.2%) and AT (-8.3%).

These data, along with submaximal exercise data and muscle biopsy electron microscopic analyses, suggest that the performance decrements were the result of detraining, rather than an impairment of aerobic metabolism due to CFS per se. These data may be indicative of central, possibly neurological, factors influencing fatigue perception in CFS sufferers.

 

Source: Rowbottom DG, Keast D, Green S, Kakulas B, Morton AR. The case history of an elite ultra-endurance cyclist who developed chronic fatigue syndrome. Med Sci Sports Exerc. 1998 Sep;30(9):1345-8. http://www.ncbi.nlm.nih.gov/pubmed/9741601

 

Treating chronic fatigue with exercise. Exercise, and rest, should be tailored to individual needs

Comment on: Putting the rest cure to rest–again. BMJ. 1998

 

 

Editor – While I welcome Sharpe and Wessely’s reminder about the dangers of bed rest,1 I am concerned about the blanket advice regarding activity levels for patients with chronic fatigue. Chronic fatigue syndrome is now generally acknowledged to be a heterogeneous condition, not a single entity with a single cause. Accordingly, what may suit one person may be totally inappropriate for another. As research has shown, most patients with chronic fatigue syndrome remain ambulant, spend relatively few daytime hours resting, are no more inactive than people with mild multiple sclerosis, and tend to perform at or near their activity ceiling.2 What these patients need is not a strict programme in which rest is allowed according to a predetermined plan but a flexible approach that does not ignore current energy levels or make people feel guilty if they increase rest periods when they consider this to be right for them.

From a theoretical perspective, inactivity may well be an important factor in chronic fatigue syndrome, but I note that Sharpe and Wessely did not provide a single reference to back their claim that many patients simply “go home and rest,” let alone that most resort to “excessive rest.” Does this mean that the theory that “excessive inactivity” perpetuates chronic fatigue syndrome is based largely on anecdotal reports and articles in magazines? Moreover, in this age of evidence based medicine, discussions of a treatment should mention the negative reports of its efficacy as well as the positive.3,4

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1113801/

 

Source: Goudsmit E. Treating chronic fatigue with exercise. Exercise, and rest, should be tailored to individual needs. BMJ. 1998 Aug 29;317(7158):599; author reply 600. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1113801/

 

Hormonal influences on stress-induced neutrophil mobilization in health and chronic fatigue syndrome

Abstract:

This investigation tested the hypotheses that women diagnosed with chronic fatigue syndrome (CFS) would exhibit significantly greater systemic indices of exercise-induced leukocyte mobilization and inflammation (neutrophilia, lactoferrin release, complement activation) than controls matched for age, weight, and habitual activity and that responses in the luteal phase of the menstrual cycle would be greater than in the follicular phase.

Subjects stepped up and down on a platform adjusted to the height of the patella for 15 min, paced by metronome. Blood samples were collected under basal conditions (the day before exercise) and following exercise for determination of circulating neutrophils and plasma concentrations of lactoferrin, C3a des arg, and creatine kinase. Complete, 24-hr urine collections were made for determination of cortisol excretion.

For all subjects, circulating neutrophil counts increased 33% (P < 0.0001) and lactoferrin increased 27% (P = 0.0006) after exercise, whereas plasma C3a des arg and creatine kinase did not increase. No indication of an exaggerated or excessive response was observed in the CFS patients compared to the controls.

In healthy women, circulating neutrophil numbers exhibited previously described relationships with physiological variables: basal neutrophil counts correlated with plasma progesterone concentrations (R = 0.726, P = 0.003) and the exercise-induced neutrophilia correlated with both urinary cortisol (R = 0.660, P = 0.007) and plasma creatine kinase (R = 0.523, P = 0.038) concentrations. These relationships were not observed in the CFS patients (R = 0.240, P = 0.370; R = 0.042, P = 0.892; and R = 0.293, P = 0.270; respectively).

These results suggest that normal endocrine influences on the circulating neutrophil pool may be disrupted in patients with CFS.

 

Source: Cannon JG, Angel JB, Abad LW, O’Grady J, Lundgren N, Fagioli L, Komaroff AL. Hormonal influences on stress-induced neutrophil mobilization in health and chronic fatigue syndrome. J Clin Immunol. 1998 Jul;18(4):291-8. http://www.ncbi.nlm.nih.gov/pubmed/9710746

 

Heterogeneity in chronic fatigue syndrome: evidence from magnetic resonance spectroscopy of muscle

Abstract:

It has been shown previously that some patients with chronic fatigue syndrome show an abnormal increase in plasma lactate following a short period of moderate exercise, in the sub-anaerobic threshold exercise test (SATET).

This cannot be explained satisfactorily by the effects of ‘inactivity’ or ‘deconditioning’, and patients with abnormal lactate responses to exercise (SATET +ve) have been found to have significantly fewer Type 1 muscle fibres in quadriceps biopsies than SATET -ve patients. We performed phosphorus magnetic resonance spectroscopy on forearm muscles of 10 SATET +ve patients, 9 SATET -ve patients and 13 sedentary volunteers.

There were no differences in resting spectra between these groups but at the end of exercise, intracellular pH in the SATET +ve patients was significantly lower than in both the SATET -ve cases and controls (P < 0.03), and the SATET +ve patients also showed a significantly lower ATP synthesis rate during recovery (P < 0.01), indicating impaired mitochondrial oxidative phosphorylation.

These observations support other evidence which indicates that chronic fatigue syndrome is a heterogeneous disorder, and confirms the view that some chronic fatigue syndrome patients have a peripheral component to their fatigue.

 

Source: Lane RJ, Barrett MC, Taylor DJ, Kemp GJ, Lodi R. Heterogeneity in chronic fatigue syndrome: evidence from magnetic resonance spectroscopy of muscle. Neuromuscul Disord. 1998 May;8(3-4):204-9. http://www.ncbi.nlm.nih.gov/pubmed/9631403

 

31P-mr spectroscopy of peripheral skeletal musculature under load: demonstration of normal energy metabolites compared with metabolic muscle diseases

Abstract:

PURPOSE: 31P-MR spectroscopy of skeletal muscle under exercise was used to obtain the range of normal variation and comparison was made for different neuromuscular diseases.

METHODS: 41 examinations of 24 volunteers and 41 investigations in 35 patients were performed on 1.5 T MR systems (Gyroscan 515 und S15/ACSII, Philips). Localised 31P-MR spectra of the calf muscle were obtained in time series with a resolution of 12 s.

RESULTS: Two types of muscle energy metabolism were identified from the pattern of spectroscopic time course in volunteers: While the first group was characterised by a remarkable decline to lower pH values during exercise, the second group showed only small pH shifts (minimum pH: 6.48 +/- 0.13 vs 6.87 +/- 0.07, p < 10(-6)) although comparable workload conditions were maintained. The pH-values correlated well with blood lactate analysis. Patients with metabolic disorders and chronic fatigue syndrome (CFS) showed decreased resting values of PCr/(PCr + Pi) and increased pH levels during exercise. PCr recovery was significantly delayed (0.31 vs 0.65 min-1, p < 0.00005) in metabolic muscle disorders but was normal in CFS patients.

CONCLUSION: Findings in volunteers indicate utilisation of different metabolic pathways which seems to be related to the fibre type composition of muscle. Reduced resting levels for PCr/(PCr + Pi), altered pH time courses, and decreased PCr recovery seem to be helpful indicators for diagnosis of metabolic muscle disorders.

Source: Block W, Träber F, Kuhl CK, Keller E, Lamerichs R, Karitzky J, Rink H, Schild HH. 31P-mr spectroscopy of peripheral skeletal musculature under load: demonstration of normal energy metabolites compared with metabolic muscle diseases. Rofo. 1998 Mar;168(3):250-7. [Article in German] http://www.ncbi.nlm.nih.gov/pubmed/9551111

Putting the rest cure to rest—again

Go home and rest” is still the advice given to many patients who complain of chronic fatigue. The refrain is echoed in self help books and magazines and adopted by many patients. What are the origins of rest as a treatment, does it work, and what evidence is there on which to base our advice to patients?

Victorian physicians diagnosed them as neurasthenia and routinely prescribed rest. This approach was typified by Silas Weir Mitchell’s “rest cure,” which was so popular as to be described as “the greatest advance of which practical medicine can boast in the last quarter of the century.” Despite such accolades, the popularity of the rest cure was short lived. By the turn of the century the same private clinics that once provided it were changing to more active treatments and to the newer psychotherapies. The years that followed saw the end of the rest cure; Karl Menninger poured scorn on the lack of psychological sophistication shown by its proponents, while Richard Asher drew attention to the “the dangers of going to bed.”

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1112768/

Comment in:

Treating chronic fatigue with exercise. Exercise improves mood and sleep. [BMJ. 1998]

Treating chronic fatigue with exercise. Exercise, and rest, should be tailored to individual needs. [BMJ. 1998]

Treating chronic fatigue with exercise. Results are contradictory for patients meeting different diagnostic criteria. [BMJ. 1998]

 

Source: Sharpe M, Wessely S. Putting the rest cure to rest—again. BMJ. 1998 Mar 14;316(7134):796. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1112768/ (Full article)

 

Muscle fibre characteristics and lactate responses to exercise in chronic fatigue syndrome

Abstract:

OBJECTIVES: To examine the proportions of type 1 and type 2 muscle fibres and the degree of muscle fibre atrophy and hypertrophy in patients with chronic fatigue syndrome in relation to lactate responses to exercise, and to determine to what extent any abnormalities found might be due to inactivity.

METHODS: Quadriceps needle muscle biopsies were obtained from 105 patients with chronic fatigue syndrome and the proportions of type 1 and 2 fibres and fibre atrophy and hypertrophy factors were determined from histochemical preparations, using a semiautomated image analysis system. Forty one randomly selected biopsies were also examined by electron microscopy. Lactate responses to exercise were measured in the subanaerobic threshold exercise test (SATET).

RESULTS: Inactivity would be expected to result in a shift to type 2 fibre predominance and fibre atrophy, but type 1 predominance (23%) was more common than type 2 predominance (3%), and fibre atrophy was found in only 10.4% of cases. Patients with increased lactate responses to exercise did have significantly fewer type 1 muscle fibres (p<0.043 males, p<0.0003 females), but there was no evidence that this group was less active than the patients with normal lactate responses. No significant ultrastructural abnormalities were found.

CONCLUSION: Muscle histometry in patients with chronic fatigue syndrome generally did not show the changes expected as a result of inactivity. However, patients with abnormal lactate responses to exercise had a significantly lower proportion of mitochondria rich type 1 muscle fibres.

 

Source: Lane RJ, Barrett MC, Woodrow D, Moss J, Fletcher R, Archard LC. Muscle fibre characteristics and lactate responses to exercise in chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 1998 Mar;64(3):362-7. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2169994/ (Full article)

 

Physical activity in chronic fatigue syndrome: assessment and its role in fatigue

Abstract:

This paper describes the assessment of physical activity in chronic fatigue syndrome (CFS) and investigated the following questions: Do patients with CFS have low levels of physical activity; is there a relationship between actual level of physical activity and fatigue; can self-report measures adequately assess actual level of physical activity; what is the role of cognitions with respect to physical activity; and are results with respect to physical activity specific to CFS?

Three different types of activity measures were used: self-report questionnaires, a 12-day self-observation list, and a motion-sensing device (Actometer) which was used as a reference for actual activity level. Fifty-one patients with CFS, 50 fatigued patients with multiple sclerosis (MS), and 53 healthy subjects participated in this study.

Although none of the self-report questionnaires showed high correlations with the Actometer, questionnaires that require simple ratings of specified activities were related to the Actometer and can be used as acceptable substitutes, in contrast to instruments that require general subjective interpretations of activity that had low or non-significant correlations with the Actometer.

Actometer results showed that CFS patients and MS patients had similar activity levels and both groups were significantly less active than healthy subjects. Compared to MS patients, CFS patients were more likely to indicate that they had been less active than other persons they knew. Activities which patients expected to result in higher fatigue levels were less frequently performed. Patients with CFS had significantly higher scores on this measure than MS patients and healthy subjects. Low levels of physical activity were related to severe fatigue in CFS but not in MS.

In conclusion, although CFS patients have similar low activity levels than MS patients, there are also important differences between both groups: in CFS cognitive factors are more prominently involved in producing the low activity levels than in MS and in CFS patients activity level is related to fatigue but not in MS.

 

Source: Vercoulen JH, Bazelmans E, Swanink CM, Fennis JF, Galama JM, Jongen PJ, Hommes O, Van der Meer JW, Bleijenberg G. Physical activity in chronic fatigue syndrome: assessment and its role in fatigue. J Psychiatr Res. 1997 Nov-Dec;31(6):661-73. http://www.ncbi.nlm.nih.gov/pubmed/9447571

 

Graded exercise in chronic fatigue syndrome. Chronic fatigue syndrome is heterogeneous condition

Comment on: Randomised controlled trial of graded exercise in patients with the chronic fatigue syndrome. [BMJ. 1997]

 

Editor—The study reported by Kathy Y Fulcher and Peter D White will provide new hope to many patients diagnosed as having the chronic fatigue syndrome.1 Before exercise regimens become the treatment of choice, however, it is worth noting that over two fifths of the patients in the study reported no or little improvement. It is a pity that the researchers did not compare those who were “very much better” with those who were not, in terms of variables such as the onset of illness (acute or gradual, history of infection) 2 and the presence of additional symptoms frequently associated with the syndrome—for example, cognitive difficulties, nausea, and malaise after exercise. This might have shown whether one particular subgroup fared better than another, allowing doctors to tailor their advice and further improve patients’ care.3

The possibility that subgroups may have different prognoses also deserves consideration. For instance, a recent study found that 70% of patients diagnosed as having epidemic neuromyasthenia recovered within two years.4 If two thirds of the subjects studied by Fulcher and White also had disease of acute onset linked to infection, one could argue that the exercise regimen reflected the natural course of the illness while the flexibility training made patients worse.

A final point concerns the 20 subjects taking full dose antidepressants. The authors do not specify why these drugs were being taken by people who did not have clinical depression or sleep disorders. Moreover, since many patients with the chronic fatigue syndrome cannot tolerate therapeutic doses of antidepressants,5 some of the reported fatigue and malaise may have been drug induced.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2127599/pdf/9361552.pdf

 

Source: Goudsmit EM. Graded exercise in chronic fatigue syndrome. Chronic fatigue syndrome is heterogeneous condition. BMJ. 1997 Oct 11;315(7113):948. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2127599/