Obesity is associated with early or prodromal respiratory dysfunction, reduced cardiorespiratory fitness, increased stress levels, and poor sleep quality, even before the onset of overt respiratory disease. Simple, non-pharmacological breathing interventions may help improve respiratory efficiency and autonomic balance in this population.

This randomized controlled trial aims to evaluate the effect of box breathing, a structured slow breathing technique, on cardiorespiratory fitness, lung function, stress levels, and quality of sleep in obese adults with prodromal respiratory dysfunction. Eligible participants will be randomly allocated to either a box breathing intervention group or a control group receiving conventional lifestyle advice.

The intervention group will practice box breathing for a prescribed duration over a period of four weeks. Outcome measures including peak expiratory flow rate, cardiorespiratory fitness parameters, perceived stress, and sleep quality will be assessed at baseline and after completion of the intervention. The findings of this study may help establish box breathing as a simple, low-cost physiotherapy-based intervention for early respiratory and cardiorespiratory dysfunction in obese adults.