Responses to Exercise Differ for Chronic Fatigue Syndrome Patients with Fibromyalgia
– Source: Medicine and Science in Sports & Exercise, Dec 12, 2011
By Dane B Cook, Benjamin H Natelson, et al.
Chronic fatigue syndrome (CFS) and fibromyalgia (FM) are chronic multisymptom illnesses with substantial clinical and diagnostic overlap.
We have previously shown that when controlling for aerobic fitness and accounting for comorbid FM, CFS patients do not exhibit abnormal cardiorespiratory responses during maximal aerobic exercise compared to healthy controls, despite differences in pain and exertion.
Purpose: The purpose of the present study was to examine cardiac and perceptual responses to steady-state, submaximal exercise [keeping below maxiumum heart rate] in CFS patients and healthy controls.
Methods: Twenty-one CFS patients [13 CFS with comorbid FM (CFS+FM) and 8 CFS only] – and 14 controls completed 20 minutes of submaximal cycling exercise.
Impedance cardiography was used to determine cardiac responses during exercise. Systolic blood pressure (SBP), perceived exertion (RPE) and leg-muscle pain were also measured. Data were analyzed using a doubly-multivariate, repeated-measures MANOVA to model the exercise response.
Results: There was a significant multivariate Time by Group interaction (p < 0.05). [Assuming by comparison with the CFS-only subjects] The CFS+FM group exhibited an exercise response characterized by:
• Higher stoke index, ventilatory equivalents for oxygen and carbon dioxide and perceived exertion,
• Lower systolic blood pressure,
• And similar heart rate responses.
The present results extend upon our previous work with maximal exercise and show that CFS and CFS+FM differ in their responses to steady-state exercise.
These results highlight the importance of accounting for comorbid conditions when conducting CFS research, particularly when examining psychophysiological responses to exercise.
Source: Medicine and Science in Sports & Exercise, Dec 12, 2011 doi: 10.1249/MSS.0b013e3182417b9a, by Cook DB, Stegner AJ, Nagelkirk PR, Meyer JD, Togo F, Natelson BH. Pain & Fatigue Study Center, Beth Israel Medical Center, New York, New York; Department of Kinesiology, University of Wisconsin-Madison, USA.