It is not known if the high total WOB in exercising women is higher due to differences in the resistive or elastic WOB. Accordingly, the purpose of this study was to determine which factors contribute to the higher total WOB during exercise in women. We performed a comprehensive re-analysis of previous data from sixteen endurance-trained subjects (8 men and 8 women) that underwent a progressive cycle exercise test to exhaustion. Esophageal pressure, lung volumes and ventilatory parameters were continuously monitored throughout exercise. Modified Campbell diagrams were used to partition the esophageal-pressure volume data into inspiratory and expiratory resistive and elastic components at 50, 75, 100 l•min^-1 and maximal ventilation and also at 3 standardized submaximal work rates (3.0, 3.5 and 4.0 W•kg^-1). The inspiratory resistive WOB at 50, 75 and 100 l•min^-1 was 67, 89 and 109% higher in women, respectively. The expiratory resistive WOB at 75 and 100 l•min^-1 was 131 and 43% higher in women, respectively. There were no significant sex-differences in the inspiratory or expiratory elastic WOB across any absolute minute ventilation. However, the total WOB and inspiratory elastic WOB were higher in men at maximal exercise ventilation. When standardized for a given work rate to body mass ratio, the total WOB was significantly higher in women at 3.5 W•kg^-1 (239±31 vs. 173±12 J•min^-1, P<0.05) and 4 W•kg^-1 (387±53 vs. 243±36 J•min^-1, P<0.05) and this was due exclusively to a significantly higher inspiratory and expiratory resistive WOB rather than differences in the elastic WOB. The higher total WOB in women at absolute ventilations and for a given work rate to body mass ratio is due to a substantially higher resistive WOB and this is likely due to smaller female airways relative to males and a breathing pattern that favours a higher breathing frequency.