Author(s): BERNARDI, M., PUGLIESE, G., CICCARELLI, A., RAGUZZINI, A., TOTI, E., FERRARA, R., SCIARRA, T., PELUSO, I. , Institution: SAPIENZA UNIVERSITY OF ROME, Country: ITALY, Abstract-ID: 2751

INTRODUCTION:
A high level of cardiorespiratory fitness (CRF) is associated with reduced prevalence of chronic non-communicable diseases (NCDs). The present study is aimed at increasing CRF and promoting beneficial lifestyle changes in sedentary and physically inactive men and women.
METHODS:
We designed a longitudinal (3 phases -P-, each one of 4 weeks and including an intermediate wash-out period) intervention study (physical activity -PA- prescription based on a cardiopulmonary exercise test -CPET- on a cycle ergometer) carried out on 16 volunteers (8 men e 8 women), characterized by a sedentary lifestyle. Participants were tested in 4 time periods (T - T0, T1, T2 and T3). Through an incremental ramp maximal CPET for each T, oxygen uptake peak (VO₂peak), ventilatory threshold (VT) and the associated heart rate (HR) were measured. Based on these results for P1 (between T0 and T1) and P3 (between T2 and T3) a minimum of 150 minutes per week of personalized PA was prescribed at the intensity of heart rate associated with VT. Participants were continuously monitored (remote access) through wearable devices (smartwatches) and they were asked to record training sessions. P2 (wash-out) did not involve any prescribed PA and participants were allowed to practice “ad libitum” PA. Data normality was assessed using the Shapiro–Wilk test. Based on the distribution of the data, two ways ANOVA was applied for normally distributed variables, whereas the Kruskal-Wallis was used for non-normally distributed variables.
RESULTS:
During the whole study we had a relevant dropout (7 participants). PA (walking and/or running and/or cycling and/or swimming) was prescribed at an intensity ranging from 66% (T0 for P1) to 76% (T2 for P3) of the HR reserve. In the group who participated in all the 3 Ps, VO₂peak in P1 significantly increased from 25.7±9.71 (T0) to 27.1±9.03 ml/kg/min (T1), did not decreased at T2 (27.5±9.67 ml/kg/min) and remained stable in T3 (27.4±10.44 ml/kg/min). A similar trend was found in the daily energy expenditure (expressed in Kcal) which increased in P1 (from 1479±212 to 1853±396), and remained high in P2 (1966±340) and P3 (1943±317).
CONCLUSION:
The present study, which unfortunately demonstrated a high dropout prevalence (44%), shows that a tailored PA protocol increases CRF in only 4 weeks of training in sedentary individuals, having also a long term impact on lifestyle (subsequent maintenance of increased daily energy expenditure and high CRF values).