Exercise Training Improves Metaboreflex Control of Sympathetic Nerve Activity in Obstructive Sleep Apnea

Abstract

BACKGROUNDWe have recently demonstrated that patients with obstructive sleep apnea(OSA) have abnormal muscle metaboreflex control of muscle sympathetic nerve activity(MSNA).OBJECTIVETo test the hypothesis that exercise training (ET) would improve muscle metaboreflex control of MSNA in patients with OSA.METHODS41 individuals with OSA(polysomnography), age = 51±1 years, BMI = 29.5±0.6 kg/m2, were randomly divided into untrained (n=21), and trained (n=20) groups. Heart rate, blood pressure, and MSNA(microneurography) were continuously measured during 4 min at rest, 3 min of handgrip static exercise (30% maximal voluntary contraction), and 2 min post handgrip muscle ischemia(PHMI). The metaborreflex sensitivity was evaluated as the difference in MSNA between first and second min PHMI and resting period. ET program was conducted for six months, three session/week. Each session consisted of 45 min of cycle ergometer, 10 min of local strengthening exercise, and 5 min of cool down.RESULTSBaseline age, BMI, exercise capacity, and hemodynamic variables were similar between groups. Likewise, the exercise and PHMI responses were not different between groups. Of note, MSNA returned to baseline during the PHMI period in both groups, which is an indicative of impaired muscle metaboreflex control. ET significantly increased exercise capacity. ET reduced MSNA levels at rest (36±3 vs. 25± 2 bursts/min), and during exercise (43±4 vs. 32± 3 bursts/min). More interestingly, MSNA remained elevated during PHMI in comparison to rest period in the exercise‐trained individuals (29±2 vs. 25± 2 bursts/min). No change in the untrained patients was found.CONCLUSIONSET decreases sympathetic nerve activity during moderate handgrip exercise and improves muscle metaboreflex control of MSNA in patients with OSA.Supported by FAPESP # 2010/15064‐6Support or Funding InformationFAPESP # 2010/15064‐6This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.