Women with Fibromyalgia (FM) have agonizing chronic pain, reduced muscular strength and demonstrate autonomic and vascular dysfunction. The purpose of this dissertation was to gain a greater understanding of the influence of acute and chronic resistance exercise on cardiovascular function in women with FM. Therefore, the 3-part goal of the present study was to evaluate the acute and chronic effects of resistance exercise on: (1) the autonomic modulation, aortic wave reflection and BP; (2) the cardiovascular responses to sympathetic stimulation induced by the cold pressor test (CPT); and (3) FBF and vasodilatory capacity in women with FM and HC.
Heart rate (HR), autonomic modulation, aortic pulse wave analysis and BP were determined at rest and during a 2-minute CPT administered before and after acute resistance exercise. Cardiac autonomic modulation was measured via heart rate variability (HRV) and was expressed in both frequency and time domains. Aortic pulse wave analysis was examined with the aortic augmentation index (AIa), the aortic AIa normalized at 75 bpm (AIa@75) and reflection time of the arterial pressure wave (Tr). BP measurements were taken using finger plethysmography. FBF and forearm vasodilatory capacity (reactive hyperemia) were measured using venous occlusion plethysmography (VOP) before and 15 min after acute resistance exercise.
There were no significant effects of CPT on autonomic indices as measured by HRV. Prior to acute resistance exercise, the CPT significantly ( p<0.05) increased HR, and altered autonomic function similarly in both groups before and after RET. There were no significant time effects of the post-exercise CPT on HR or autonomic modulation.
There were no significant effects of RET on HRV at rest or during recovery of resistance exercise. There were no group differences for the AIa and Tr during any condition or time. The post-exercise increased AIa with a greater magnitude compared to the pre-exercise CPT (p<0.05) at Pre2 and Post, but not at Pre1. Tr was lower during the post-exercise CPT compared to recovery before RET. There was no effect of resistance exercise or CPT on digital systolic BP (SBP). Digital diastolic BP (DBP) and the aortic DBP were significantly reduced (p<0.05) by the pre-exercise CPT, acute resistance exercise and the post-exercise CPT compared to rest before and after RET. Both aortic and digital pulse pressures (PP) were significantly increased (p<0.05) above rest during the pre-exercise CPT, recovery from resistance exercise and the post-exercise CPT before and after RET. However, aortic and digital mean arterial pressures (MAP) were significantly decreased ( p<0.05) compared to rest during the pre-exercise CPT, recovery from resistance exercise and the post-exercise CPT at all time periods for each group. There were no group differences for vascular measurements at any condition and time point. Pre-exercise FBF increased significantly ( p<0.05) after RET in women with FM (pre: 4.2 ± 2.7 vs. post: 8.3 ± 4.8 ml/min/100 ml of blood) and HC (pre: 3.2 ± 2.0 vs. post: 4.6 ± 3.1 ml/min/100 ml of blood). Post-exercise FBF increased significantly with RET in both groups of women (FM: +36.1% vs. HC: +29.5%; p<0.05). After RET, pre-exercise peak vasodilatory capacity increased in women with FM (Pre: 10.4 ± 4.6; Post: 19.2 ± 11.5 ml/min/100 ml of blood; p<0.05) and HC (pre: 9.7 ± 5.3; post: 13.5 ± 8.3 ml/min/100 ml of blood; p<0.05). Post-exercise peak vasodilatory capacity also increased significantly (p<0.05) in women with FM (+36%) and HC (+23.6%) after RET.
In summary, it was observed that FM patients generally exhibited normal autonomic responses to physical stress (CPT or acute exercise). Both HC and women with fibromyalgia adapted to RET with expected increases in maximal strength. In addition, RET increased maximal forearm vasodilatory capacity in both HC and in women with FM, while having minimal effects on autonomic tone. Nonetheless, it was observed that RET markedly decreased the severity of FM, effectively curing FM in some of these patients. It is concluded that RET reduces severity of FM without inducing major adaptations in autonomic function. (Abstract shortened by UMI.)