Objective: To evaluate if high-intensity interval training three times weekly for 12 weeks improves asthma control in overweight, postmenopausal women with uncontrolled, late-onset asthma. Methods: The reported study is a randomized clinical pilot study (www.clinicaltrials.gov; NCT03747211) that compared 12 weeks of high-intensity interval training (spinning) with usual care. The five-question Asthma Control Questionnaire (ACQ-5) was used as primary outcome. Secondary measures included systemic inflammation and inflammation of the airways, body composition, and cardiac function during exercise. Results: We included 12 women with asthma (mean age 65 years (SD 6); mean body mass index 30 kg/m² (SD 2)) from whom eight were randomized to exercise and four to control. Baseline ACQ-5 was 1.95 (SD 0.53) in the control group and 2.03 (0.54) in the exercise group. Patients had a mean blood eosinophil level of 0.16 × 10⁹cells/L (SD 0.07) and a mean fraction of exhaled nitric oxide of 23 ppb (SD 25). Mixed models showed that participants in the exercise group reduced their ACQ-5 by 0.55 points (95%CI −1.10 to −0.00; P = 0.08) compared with the control group. The exercise group significantly reduced their mean body fat percentage (−2.7%; 95%CI −4.5 to −0.8; P = 0.02), fat mass (−2.8 kg; 95%CI −5.1 to −0.4; P = 0.044) and android fat mass (−0.33 kg; 95%CI −0.60- −0.06; P = 0.038). In analyses of cardiac measures, we saw no significant effects on right ventricular function (fractional area change), diastolic function or left ventricular function. Conclusions: Although changes in ACQ-5 were slightly insignificant, these preliminary findings indicate that aerobic exercise training can be used as a means to improve asthma control in overweight, postmenopausal women with asthma.