Date of Award
Bachelor of Applied Sciences Honours
Faculty of Science, Technology and Engineering
Dr Colin James
Dr Paul Sacco
Chronic fatigue syndrome (CFS) and Overtraining syndrome (OTS) are separate, complex conditions which have so many similar debilitating effects that it has led some researchers to conclude that OTS is a sub-condition of CFS. The purpose of this research was to compare the force and damage-recovery characteristics of skeletal muscle in CFS patients and control normals, after a single damaging bout of eccentric contractions in the non-dominant forearm flexors. The subjects ( n = 25 ), a convenience sample were assigned to three groups; [I] CFS + eccentric damage (n = 8),  Control Damage (CD)+ eccentric damage (n = 10), and  Control (ND) + no damage (n = 7). The research was carried out over a four week period using the following format. CFS & CD groups received eccentrically induced muscle damage of the forearm flexors by 35 isokinetic eccentric (7 x 5, 2 minutes recovery between sets) contractions at 90° sec-1 with the forearm returning passively at 15°sec-1 Testing was undertaken pre-damage and I, 2, 4, 6, 8, 12, 16, 20, 24, & 28 days post-damage, by measurements of voluntary maximal concentric isokinetic force at 150°sec-1, isometric maximal voluntary contraction at approximately 90° elbow flexion, electrically stimulated 20 : 50Hz isometric force ratio at approximately 90° elbow flexion, muscle pain, and blood CK. Groups were compared on these variables using Students independent t-test and repeated measures two way ANOVA with simple contrasts. Alpha was set at 0.05 level. The results of this study were significant for the eccentric force produced in the damage bout with the CFS group producing less force after the 4th set (p < 0.05). Serum CK concentration, which following eccentric damage was significantly higher in the CFS group than the CD group (p < 0.01), and the ND group (Q < 0.001). The low frequency fatigue (LFF) ratio was significantly lower in the CFS group 2, 4, 6 & 8 days post-damage when compared to the CD group. Maximal isometric voluntary force and isokinetic concentric peak torque (PT) & average peak torque (AT) loss was significantly greater in the CFS group compared to the CD group (isometric 12 < 0.01, PT 12 < 0.01; & AT Q < 0.001) and ND group (isometric TI < 0.01; PT TI < 0.001; & AT 12 < 0.001 ). The intensity of delayed onset muscle soreness (DOMS) was significantly less 6 days post-damage in the CFS group, when compared to the CD group (TI < 0.05). The combination of an increased CK efflux and low frequency fatigue, that is of both greater depth and longer lasting, together with greater isometric and concentric force losses, indicates that the subjects with CFS have a lower threshold for muscular damage, that is more profound and slower to recover than in healthy individuals.
Wright, D. L. (1995). Eccentrically Induced Skeletal Muscle Damage in Patients With Chronic Fatigue Syndrome (CFS), With Reference to Overtrained Athletes. Retrieved from http://ro.ecu.edu.au/theses_hons/452