Preservation of nutritional status and of fat-free mass (FFM) and/or preventing of fat mass (FM) accumulation have a positive impact on well-being and prognosis in asthma patients. Physical inactivity is identified by World Health Organization as the fourth leading risk factor for global mortality. Physical activity (PA) may contribute to limit FM accumulation, but little information is available on the interactions between habitual PA and body composition and their association with disease severity in asthma severity. Associations between habitual PA, FM, FFM, and pulmonary function were investigated in 42 subjects (24 patients with mild-moderate asthma and 18 matched control subjects). Sensewear Armband was used to measure PA and metabolic equivalent of tasks (METs) continuously over 4 days, while body composition was measured by bioelectrical impedance analysis. Respiratory functions were also assessed in all study participants. FM and FFM were comparable in mild-moderate asthmatics and controls, but PA was lower in asthmatics and it was negatively correlated with FM and positively with the FFM marker body cell mass in all study subjects (P < 0.05). Among asthmatics, treated moderate asthmatics (ICS, n = 12) had higher FM and lower PA, METs, steps number/die, and forced expiratory volume in the 1st second (FEV1)/forced vital capacity (FVC) than in untreated intermittent asthmatics (UA, n = 12). This pilot study assesses that in mild-moderate asthma patients, lower PA is associated with higher FM and higher disease severity. The current results support enhancement of habitual PA as a potential tool to limit FM accumulation and potentially contribute to preserve pulmonary function in moderate asthma, considering the physical inactivity a strong risk factor for asthma worsening.
