Weight loss reduces dyspnea on exertion in obese women

•Moderate weight loss effectively reduced dyspnea on exertion (DOE) in obese women.•Oxygen cost of breathing decreased following weight loss.•Body composition and pulmonary function improved with weight loss.•Reduction in DOE was not significantly associated with physiological changes measured.

During submaximal exercise, some otherwise healthy obese women experience breathlessness, or dyspnea on exertion (+DOE), while others have mild or no DOE (−DOE). We investigated whether weight loss could reduce DOE. Twenty nine obese women were grouped based on their Ratings of Perceived Breathlessness (RPB) during constant load 60 W cycling: +DOE (n = 14, RPB ≥ 4, 34 ± 8 years, and 36 ± 3 kg/m2) and −DOE (n = 15, RPB ≤ 2, 32 ± 8 years, and 36 ± 4 kg/m2) and then completed a 12-week weight loss program. Both groups lost a moderate amount of weight (+DOE: 6.6 ± 2.4 kg, −DOE: 8.4 ± 3.5 kg, and p < 0.001). RPB decreased significantly in the +DOE group (from 4.7 ± 1.1 to 3.1 ± 1.6) and remained low in the −DOE (from 1.5 ± 0.7 to 1.6 ± 1.1) (interaction p < 0.002). Most physiological variables measured (i.e. body composition, fat distribution, pulmonary function, oxygen cost of breathing, and cardiorespiratory measures) improved with weight loss; however, the decrease in RPB was not correlated with any of these variables (p > 0.05). In conclusion, moderate weight loss was effective in reducing breathlessness on exertion in obese women who experienced DOE at baseline.