EFFECT OF ENDURANCE EXERCISE ON BRAIN NATRIURETIC PEPTIDE (BNP)

OBJECTIVE: To evaluate the effect of maximal exercise on the level of brain natriuretic peptide (BNP) and cardiac adaptive changes in endurance trained elite athletes and sedentary healthy subjects.METHODOLOGY: This Cross-sectional comparative study was conducted at Army Medical College in collaboration with Armed Forces Institute of Cardiology (AFIC) Rawalpindi. Twenty two elite endurance athletes (Long Distance Runners) and 22 matching sedentary (from same unit having no sports activity) controls were selected by convenience (non-probability) sampling technique. Height, body weight, blood pressure,pulse rate and ECG were recorded. The blood was drawn from antecubital vein for measuring BNP and aldosterone before exercise and again after exercise. The echocardiography of left ventricle was done to measure the end-diastolic internal diameter (LVIDd), diastolic interventricular septal thickness (IVSTd), and diastolic posterior wall thickness (PWTd). The left ventricular mass (LVM) was calculated by Devereux formula. The data were recorded in a proforma and analyzed by SPSS version 10.RESULTS: It was observed that the heart rate and blood pressure of athletes were significantly less than the controls (p 0.001); while LVIDd,IVST, PWTd, and LVM was greater in athletes than controls (p 0.001).Pre-exercise BNP level was 45.29+18.69 pmol/l 34.16+13.74 pmol/lwhile post-exercise BNP level was 58.32+19.65 pmol/l 43.638+11.82pmol/l in athletes and controls respectively (p 0.01). Pre-exercise Aldosterone level was 15.34+2.77 ng/dl 13.05+2.134 ng/dl while post-exercise BNP level was 16.01+2.14 ng/dl 14.65+2.30 ng/dl in athletes and controls respectively (p 0.01).CONCLUSION: The maximal exercise increases the level of BNP in elite athletes significantly.