Exercise effects on middle-aged women exercise tolerance and left ventricular global longitudinal strain

Abstract

Objective To evaluate the effects of regular exercise training on exercise tolerance and left ventricular global longitudinal stain (GLS), and the association between exercise capacity and GLS. Methods The 60 apparently healthy middle-aged female were prospectively enrolled and examined at baseline and after 12 weeks. Volunteers were separated into 3 groups: moderate intensity training (MIT) group [n=28, (51.0±5.6) years], high intensity intermittent training (HIIT) group [n=20, (50.1±6.0) years] underwent regular exercise training (cycling for 50 minutes, 3 times a week) for 12 weeks, and control group [n=12, (48.7±4.7) years] without exercise training. CPET, echocardiogram, fasting blood glucose and blood lipoids were assessed. GLS was evaluated with speckle tracking technology. Statistical analyses were performed using the SPSS 22.0 software. Results There was no difference between groups at baseline. In MIT group, PVO2 [(22.95±4.85)ml·min-1·kg-1vs. (23.86±5.02)ml·min-1·kg-1,P=0.041] and GLS (-20.24%±3.03% vs. -21.74%±2.75%, P=0.017) significantly improved following exercise training. In HIIT group, PVO2 [(21.17±3.25)ml·min-1·kg-1vs. (22.97±3.04)ml·min-1·kg-1,P=0.002] and GLS (-20.06%±3.11% vs. -22.09%±1.94%, P=0.008) also improved. After 12 weeks, ΔPVO2 (PVO2 after 12 weeks minus PVO2 at baseline) and ΔGLS (GLS after 12 weeks minus GLS at baseline) in HIIT group were significantly better than control group. Meanwhile, these two variables were better in HIIT group than in MIT group, but there was no significant difference. In correlation analysis, ΔPVO2 and ΔGLS were significantly correlated (r=-0.358, P=0.012), while ΔPVO2 showed no relationship with ΔLVEF and ΔE/e'. In multiple regression analysis, ΔGLS was an independent determinant of ΔPVO2 (β=-0.362, P=0.014). Conclusions In apparently healthy middle-aged women, exercise tolerance and GLS were improved following regular exercise training, presumably that the improvement of GLS is an independent contributor of elevated exercise tolerance. Key words: Exercise training; Middle-aged women; Exercise tolerance; Left ventricular global longitudinal strain