Anaerobic exercise capacity in patients with juvenile‐onset idiopathic inflammatory myopathies

OBJECTIVE: To 1) report the feasibility of an "all-out" 30-second cycling exercise test (Wingate Anaerobic Exercise Test [WAnT]) in juvenile-onset idiopathic inflammatory myopathy (JIIM) patients, 2) describe the anaerobic exercise capacity in juvenile dermatomyositis patients, and 3) determine if the anaerobic exercise capacity could be related to disease duration or disease phase. METHODS: Twenty patients (age 14.13 +/- 5.4 years) with JIIM participated in this study. All patients were able to perform the WAnT without adverse events. RESULTS: Comparison with healthy controls revealed a -29.3 +/- 26.58% (P = 0.001) and -27.6 +/- 25.7% (P = 0.002) impairment in mean power and peak power on the WAnT, respectively. The WAnT correlated with disease phase and with knee extensor muscle strength. CONCLUSION: The WAnT might be a valuable adjunct next to other assessment tools in the followup of JIIM patients.