37 research outputs found
Adaptive dispersion equalisation by detecting dispersion fluctuations using PM-AM conversion
A simplified procedure in radioisotope dilution method for the mercury inventory of electrolytic chlorine cells
Submaximal exercise testing with near-infrared spectroscopy in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients compared to healthy controls: a case–control study
Background:
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating illness. Symptoms include profound fatigue and distinctive post-exertional malaise (PEM). We asked whether a submaximal exercise test would prove useful for identifying different patterns of tissue oxygen utilization in individuals with ME/CFS versus healthy subjects. Such a test has potential to aid with ME/CFS diagnosis, or to characterize patients’ illness.
Methods:
A case–control study of 16 patients with ME/CFS compared to 16 healthy controls completing a 3-min handgrip protocol was performed. Response was measured using near-infrared spectroscopy, resulting in measurements of oxygenated (O₂Hb) and deoxygenated hemoglobin (HHb) over wrist extensors and flexors. Changes in O₂Hb (delta (d)O₂Hb) and HHb (dHHb) absorbance between the first and last contraction were calculated, as were the force–time product of all contractions, measured as tension-time index (TTI), and ratings of perceived exertion (RPE).
Results:
Individuals with ME/CFS demonstrated smaller dOâ‚‚Hb and dHHb than controls. However, after adjusting for TTI and change in total hemoglobin (delta (d)tHb), differences in dOâ‚‚Hb and dHHb were reduced, with large overlapping variances. RPE was significantly higher for cases than controls, particularly at rest.
Conclusions:
Relative to controls, participants with ME/CFS demonstrated higher RPE, lower TTI, and reduced dOâ‚‚Hb and dHHb during repetitive handgrip exercise, although considerable variance was observed. With further study, submaximal exercise testing may prove useful for stratifying patients with a lower propensity for inducing PEM, and have the ability to establish baseline intensities for exercise prescription.Medicine, Department ofPhysical Therapy, Department ofPopulation and Public Health (SPPH), School ofNon UBCMedicine, Faculty ofOther UBCReviewedFacult