| Physical activity is known to improve physical fitness and to reduce mortality and morbidity from numerous clinical
conditions. Regular exercise decreases sympathetic activity, reactivity and increase in vagal tone. The amount of HRV
represents the physiologic and psychological health. There is positive relation seen between physical activity and variables
of lung function .Goal of present study is to establish the role of regular exercise to improve HRV and lung function . The
present study was conducted at Sree Lakshmi Narayana Institute of Medical Sciences, Pondicherry The major purpose of
this analytic type of observational study is to explore the role of physical activity on cardiorespiratory fitness in healthy
people. 90 subjects of age group 18-25 years divided into three groups. Each group is having 30 subjects. Subjects were
divided into three groups according to leisure time physical activity assessed by metabolic equivalent minutes/week.
Variables of lung function recorded were FEV1, FEV1/FVC, PEFR, F EF25-75, and MVV. After 15 min of rest in supine
posture continuous ECG for 5 min recorded and heart rate variability was calculated. Hence regular physical activity is
associated with increased HRV,improved lung function ,reduced sympathetic activity and increased parasympathetic
tone.The results of present study were analysed, each group was compared by using ANOVA. p value <0.05 were
considered significant .FVC, FEV1, FEV1/FVC increased significantly with increase in physical activity (p<0.05) whereas
FEF 25-75% and MVV showed highly significantly increase (p<0.001). Results of HRV showed that LF abpower,LFnu
and LF/HF ratio decrease significantly with increase in physical activity whereas HF ab power, HFnu and Tpower increase
significantly with increase in physical activity. Present study strongly suggests that the intensity or severity of the sports
determines the extent of strengthening of the respiratory muscles with a resultant increase in the lung volumes. Present
study showed that regular physical activity is associated with increased HRV, reduced sympathetic activity and increased
parasympathetic tone and improved cardiorespiratory health. Moderate amount of exercise(1500MET minutes per week-
3000 METminutes per week) is sufficient to increase HRVddd |
