PURPOSE: To assess 16-weeks improvements of physical fitness, metabolic and psychologic parameters in people living with HIV (PLWH) exercising with the support of a smartphone application, as compared to a control group exercising without application.METHODS: This was a randomized, open-label, pilot study enrolling PLWH in a 16-week protocol consisting of moderate physical activity three times/week, which included an initial coach-supervised period of 4 weeks, followed by 12 weeks where participants trained independently. Participants were allocated to either an experimental group that trained with the use of a smartphone application (APP) or a control group that practiced following a hard copy training program (No-APP). At baseline (BL) and after 16-weeks (W16), patients were assessed for cardiorespiratory fitness, body composition, blood lipid profile, and profile of mood states (POMS).RESULTS: Forty-eight PLWH were screened and 38 were eligible: 20 were allocated to the APP group and 18 to the No-APP group. Two APP and two No-APP participants were lost to follow-up. Intention-to-treat analysis showed a W16 improvement from BL of ≥15% V[Combining Dot Above]O2peak in 13 of 18 (72%) in APP, but only in 3 of 16 (19%) in No-APP participants (p=0.025). Significant W16 improvements were observed in APP, but not in No-APP participants, in V[Combining Dot Above]O2peak, fat mass and fat-free mass %, total-, LDL-cholesterol and triglycerides, vigour and total mood by POMS. Accordingly, significant % change differences between the APP and the No-APP groups were observed in V[Combining Dot Above]O2peak, fat and fat-free mass %, total-, LDL-cholesterol and triglycerides, and in depression, vigour, anger and total mood by POMS.CONCLUSIONS: Exercising with the use of a smartphone application improved cardiorespiratory fitness, body composition, cholesterol profiles and psychological outcomes in PLWH.