Effects of neuromuscular electrical stimulation on exercise capacity, muscle strength, physical activity, and quality of life in patients with interstitial lung diseases: A randomized study.

BACKGROUND

Neuromuscular electrical stimulation (NMES) has been investigated for various cardiopulmonary conditions; however, its effects on interstitial lung disease (ILD) remain poorly understood.

OBJECTIVE

To investigate the effects of NMES on exercise capacity, muscle strength, quality of life, and physical activity in ILD patients.

METHODS

This was a prospective, randomized, controlled, triple-blinded study. Nineteen patients in the NMES group received NMES on the bilateral quadriceps femoris (QF) at 40 Hz for 20 min, three times a week for six weeks, along with daily respiratory exercises. Eighteen patients in the control group performed respiratory exercises alone for six weeks. Outcomes measured before and after included: 6-min walk test (6MWT), incremental shuttle walk test (ISWT), maximum inspiratory and expiratory pressures (MIP, MEP), QF muscle strength, quality of life (SGRQ, LCQ), physical activity, dyspnea (MMRC scale), and fatigue (FSS).

RESULTS

The NMES group demonstrated significant improvements in 6MWT distance, MMRC, energy expenditure, physical activity duration, and daily step count, with increased FSS scores compared to the control group (p = 0.025). No significant differences were observed between groups for ISWT, MIP/MEP, SGRQ, or LCQ scores (p > 0.05). While 6MWT distance improved (p = 0.002), QF muscle strength was preserved within the NMES group but decreased within the control group (p = 0.018).

CONCLUSION

NMES is a feasible and effective intervention for enhancing exercise capacity and physical activity levels, while preserving muscle strength and reducing dyspnea in patients with ILD. This implies that incorporating NMES into the rehabilitation programs of ILD patients may enhance their overall physical performance and quality of life.