| Abstract: | Background: Physical activity (PA) is known to be able to reduce Chronic Kidney Disease (CKD) mortality, but the effect was perceived as too little, too late to motivate exercisers. However, smart types of exercise could be employed to double the effect by simultaneously lowering resting heart rate (RHR). The added role of RHR in enlarging the benefits of physical activity to prevent or to reduce CKD has not been reported. Methods: A medical screening cohort of 680,277 adults in Taiwan was successively recruited during 1996-2017, and 64,577 deaths were identified by National Death File and 5,671 cases of ESRD after a medium follow up of 18 years. CKD was analyzed by 5 component stages, eGFR values and proteinuria tested by dipstick. RHR came from electrocardiogram taken after rest in a supine position, with 80-99/min considered as elevated but within normal limits. Physical activity was expressed as MET-h/week, which was a product of exercise intensity and duration. Exercise status was classified as inactive, low, medium high or very high active. The association of RHR with CKD at entry points or with various CKD associated all-cause mortality risks during follow up was both calculated by Cox model. Results: A triangular interactive relationship existed among PA, RHR and CKD, with PA able to reduce both RHR and CKD and with RHR associated with less CKD when slowed down by PA. Increasing RHR per 10 beats from 60/min up was associated with 30% increase in CKD, 39% increase in proteinuria and 30% increase in GFR<45. Physical activity, as officially recommended, was associated with 18% reduction of CKD, with the more vigorous intensity, the larger the reduction. It was also inversely associated with RHR, and vigorous intensity exercise for 3 months was associated with a lowering of RHR by 11 beats/min. Not all PA could slow RHR, mostly by those with vigorous intensity. Most CKD people were inactive (>80%) and could benefit from engaging in all types of PA recommended. When participants exercised, majority (60%) lowered RHR and small minority (9%) increased RHR, with remaining unchanged. Conclusions: The incidence and mortality of CKD and proteinuria could be maximally reduced by vigorous physical activity when RHR was simultaneously lowered. Promoting the kind of exercise that reduced RHR may double the reduction of CKD or proteinuria. |
