Physical Training in Patients With Idiopathic Inflammatory Myopathies

Patients will undertake a maximal graded exercise test on a treadmill, with increments in velocity and grade at every minute until volitional exhaustion. VO2peak will be considered as the average of the final 30 s of the test. Ventilatory threshold (VAT) will be determined when ventilatory equivalent for VO2 (VE/VO2) increased without a concomitant increase in ventilatory equivalent for carbon dioxide (VE/VCO2). Respiratory compensation point (RCP) will be determined when VE/VO2 and VE/VCO2 increased simultaneously.

Blood samples will be centrifuged at 3000 rpm for 15 min at 4°C, and the serum aliquot will be stored at -80°C for subsequent analyses. Cytokines (i.e., IL-6, TNF alpha, IFN gamma) will be measured using a multiplex human panel (Milliplex Map, Millipore, Billerica, MA, USA). Data analysis will be performed through Luminex xMAP Technology, according to the manufacturer's instructions.

The dynamic 1-RM for the leg-press and the bench-press exercises, arm curl (with the dominant arm).

After local anesthesia, a cutaneous incision will be made in lateral thigh face. The biopsy will be done using the Bergstrom needle. Histological (hematoxylin and eosin)/immunohistochemical (CD4, CD8, CD68, CD20, C5b-9, MHCI, MHCII, CD31) analysis will be performed in muscle samples (at baseline and after 12 weeks) in all patients (present study)

Isometric strength (assessed by handgrip, with the dominant arm) will be assessed at baseline and after the intervention. Muscle function will be evaluated through the TUG and the TST tests.

This partially validated tool measures the degree of disease activity of extra-muscular organ systems and muscle. This is a combined tool that includes the Myositis Disease Activity Assessment Visual Analogue Scales (MYOACT), which is a series of physician's assessments of disease activity, and the Myositis Intention to Treat Activity Index (MITAX).

This partially validated tool measures the serum activities of at least 2 of the 4 muscle-associated enzymes including creatine phosphokinase (CK), the transaminases (ALT, AST), lactate dehydrogenase (LD) and aldolase.

Especific questionnaire (health assessment questionnaire). Pontuaction 0.00-3.00

This partially validated tool assesses muscle strength using manual muscle testing (MMT). A 0 - 10 point scale is proposed for use. An abbreviated group of 8 proximal, distal, and axial muscles performs similarly to a total of 24 muscle groups, and is also proposed for use for research studies.

This partially validated tool measures the global evaluation by the patient, or by the parent if the patient is a minor, of the patient's overall disease activity at the time of assessment using a 10 cm. visual analogue scale.

This partially validated tool measures the global evaluation by the treating physician of the overall disease activity of the patient at the time of assessment using a 10 cm. visual analogue scale and a 5 point Likert scale.