Exercise responses in patients with chronically high creatine kinase levels. Issue 2 (29th March 2017)

• Record Type: Journal Article
• Authors: Cooper, Christopher B.; Dolezal, Brett A.; Neufeld, Eric V.; Shieh, Perry; Jenner, John R.; Riley, Marshall
• Is Part Of: Muscle & nerve. Volume 56:Issue 2(2017)
• Page Start: 264
• Page End: 270
• Publication Date: 2017-03-29
• Subjects: ammonia -- creatine kinase -- exercise testing -- lactate -- myopathy; Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.25508
• Languages: English
• ISSNs: 0148-639X

Abstract

ABSTRACT: Introduction: Elevated serum creatine kinase (CK) is often taken to reflect muscle disease, but many individuals have elevated CK without a specific diagnosis. How elevated CK reflects muscle metabolism during exercise is not known. Methods: Participants (46 men, 48 women) underwent incremental exercise testing to assess aerobic performance, cardiovascular response, and ventilatory response. Serum lactate, ammonia, and CK were measured at rest, 4 minutes into exercise, and 2 minutes into recovery. Results: High‐CK and control subjects demonstrated similar aerobic capacities and cardiovascular responses to incremental exercise. Those with CK ≥ 300 U/L exhibited significantly higher lactate and ammonia levels after maximal exercise, together with increased ventilatory responses, whereas those with CK ≥200 U/L but ≤ 300 U/L did not. Conclusions: We recommend measurement of lactate and ammonia profiles during a maximal incremental exercise protocol to help identify patients who warrant muscle biopsy to rule out myopathy. Muscle Nerve 56 : 264–270, 2017