p23 GET therapist manual:
MODEL AND RATIONALE BEHIND GET
GET has been shown to improve muscle strength, cardiovascular endurance, and symptoms in a wide variety of illnesses,[4] including fibromyalgia, a painful fatiguing illness related to CFS/ME.[5] Three systematic reviews have concluded that GET is a promising treatment for outpatients with CFS/ME.[6-8] Five randomised controlled trials (RCTs) have found improved fatigue and disability with differing graded exercise programmes compared to no treatment or control treatments.[1,2,9-11] Three randomised controlled trials of graded exercise suggest that GET improves symptoms or disability more than relaxation or supportive therapy.[1,10,11]
The rationale behind GET stems from both physical and behavioural understanding of CFS/ME. Physical deconditioning, exercise intolerance and avoidance caused by relative inactivity are reversed by gradually and carefully re-introducing regular physical exercise, aiming to return a patient to normal health and ability. This model has been used in previous trials.[1,2,11] Exercise also has a role to play in improving the sleep disturbance, mood, and cognitive problems found in people with CFS/ME.[10]
The most prominent symptom of CFS/ME is post-exertional fatigue, resulting in avoidance of exercise, exercise intolerance, and reduced aerobic capacity.[12-14] One study has also shown significantly lower isometric quadriceps strength.[14] Prolonged inactivity can perpetuate or worsen fatigue and its associated symptoms in both healthy volunteers [13] and in people recovering from a viral illness.[15]
Physical deconditioning is characterised by reduced muscle strength and aerobic capacity.[13] This has been supported by a number of exercise studies that have shown reduced exercise tolerance in CFS/ME patients compared to controls. Five case-control studies have found that exercise tolerance was significantly reduced in CFS/ME participants.[14,16,17,18,19]. A further small study found nearly two minutes difference in an exercise test compared to controls.[20] A seventh study also concluded that exercise tolerance was reduced, although time spent exercising was not given.[21] Six of these studies also found that people with CFS/ME were either more deconditioned than healthy controls or at least as deconditioned as sedentary healthy controls [14,16-20]. Only two studies found no significant differences from healthy controls,[22,23] although both patients and controls were less fit than predicted.[22] However, CFS/ME participants in these two studies had significant correlations between deconditioning and both fatigue and functional impairment, and a negative correlation with physical activity,[22] suggesting that deconditioning was important even in these apparently negative studies.[22,23] Studies also show exercise incapacity was significantly correlated with reduced muscle strength and/or higher heart-rate response to sub-maximal exercise in people with CFS/ME.[11,14] The latter may be related to reduced left ventricular mass found in CFS/ME.[24] A graded exercise programme produced a 13 per cent increase in peak VO2 and a 26 per cent increase in quadriceps muscle strength.[1,14] Improved exercise capacity was also correlated with reduced heart-rate response to sub-maximal exercise.[14]
1. Fulcher KY & White PD. Randomised controlled trial of graded exercise in patients with the chronic fatigue syndrome. BMJ 1997;314:1647-52.
2. Powell P et al. A randomised controlled trial of patient education to encourage graded exercise in chronic fatigue syndrome. BMJ 2001;322:387-92.
3. Fulcher KY & White PD. Chronic fatigue syndrome: a description of graded exercise treatment. Physiotherapy 1998;84:223-6.
4. Basmajian JV & Wolf SL. Therapeutic Exercise. Baltimore, Williams & Wilkins, 1990.
5. Busch A, Schachter CL, Peloso PM, Bombardier C. Exercise for treating fibromyalgia syndrome. Cochrane Database Syst Rev 2002; 3:CD003786.
6. Whiting P, Bagnall A, Sowden A, Cornell J, Mulrow C, Ramirez G. Interventions for the treatment and management of chronic fatigue syndrome: a systematic review. JAMA 2001;286:1360-8.
7. Bagnall AM et al. A systematic review of interventions for the treatment and management of chronic fatigue syndrome and/or myalgic encephalomyelitis.
www.york.ac.uk/inst/crd/cfs.htm 2001.
8. Edmonds M, McGuire H, Price J. Exercise therapy for chronic fatigue syndrome. Cochrane Database Syst Rev. 2004(3):CD003200.
9. Wearden AJ et al. A randomised, double-blind, placebo-controlled trial of fluoxetine and graded exercise for chronic fatigue syndrome. Br J Psychiatry 1998;172:485-90.
10. Wallman K, Morton A, Goodman C, et al. Randomised controlled trial of graded exercise therapy for chronic fatigue syndrome. Med J Australia 2004;180:444-8.
11. Moss-Morris R, Wash C, Tobin R, Baldi JC. A randomised controlled graded exercise trial for chronic fatigue syndrome: outcomes and mechanisms of change. J Health Psychol (in press).
12. Royal Colleges. Chronic Fatigue Syndrome; Report of a joint working group of the Royal Colleges of Physicians, Psychiatrists and General Practitioners. London, Royal College of Physicians, CR54, 1996.
13. Sandler H, Vernikos J. Inactivity: physiological effects. London: Academic Press, 1986.
14. Fulcher KY & White PD. Strength and physiological response to exercise in patients with the chronic fatigue syndrome. J Neurol Neurosurg Psychiatry 2000;69:302-7.
15. Dalrymple W. Infectious mononucleosis: 2. Relation of bed rest and activity to prognosis. Postgrad Med 1961;35:345-349.
16. DeBecker P et al. Exercise capacity in chronic fatigue syndrome. Arch Intern Med 2000;160:3270-7.
17. Fischler, B, Dendale P, Michiels V, Cluydts R, Kaufman L, De Meirleir K. Physical fatigability and exercise capacity in chronic fatigue syndrome: association with disability, somatisation and psychopathology. J Psychosom Res 1997;42:369-78.
18. Riley MS, O’Brien CJ, McCluskey DR, Bell NP, Nicholls DP. Aerobic work capacity in patients with chronic fatigue syndrome. BMJ 1990;301:953-6.
19. Sisto SA, Lamanca J, Cordero DL et al. Metabolic and cardiovascular effects of a progressive exercise test in patients with chronic fatigue syndrome. Am J Med 1996;100:634-40.
20. Gibson J, Carroll N, Clague JE, Edwards RHT. Exercise performance in fatiguability in patients with chronic fatigue syndrome. J Neurol Neursurg Psychiatry 1993;56:993-8.
21. Inbar O, Dlin R, Rootstein A, Whipp BJ. Physiological responses to incremental exercise in patients with chronic fatigue syndrome. Med Sci Sports Exerc 2001;33:1463-70.
22. Bazelmans E, Bleijenberg G, Van Der Meer JWM, Folgering H. Is physical deconditioning a perpetuating factor in chronic fatigue syndrome? A control study on maximal exercise performance and relations with fatigue, impairment and physical activity. Psychol Med 2001;31:107-14.
23. Sargent C, Scroop GC, Nemeth BN, Burnet RB, Buckley JD. Maximal oxygen uptake and lactate metabolism are normal in chronic fatigue syndrome. Med Sci Sports Exerc 2002;34:51-6.
24. De Lorenzo F, Xiao H, Mukherjee M et al. Chronic fatigue syndrome: physical and cardiovascular deconditioning. Q J Med 1998;91:475-81.