Effect of Age and Acute-Moderate Intensity Exercise on Biomarkers of Renal Health and Filtration

SIMPLE SUMMARY: In this research manuscript, the authors demonstrate that when assessing renal health and filtration after an acute bout of moderate-intensity aerobic exercise in healthy individuals of varying ages, only renal function is altered via contemporary biomarker cystatin C, indicating actual changes in renal filtration are not solely due to concentration changes seen in traditional markers of renal function. The clinical application of this study is understanding the value that maintaining good health through the middle-age years offers in the prevention of renal decline. Additionally, healthy individuals appear to have a limit on how high renal health and filtration can be obtained, and in the absence of cardiometabolic diseases, exercise minimally influences renal health and filtration. ABSTRACT: Aerobic exercise elicits a multitude of physiological improvements in both healthy and diseased populations. However, acute changes in renal health and filtration with aerobic exercise remain difficult to quantify by traditional biomarkers to estimate glomerular filtration rate (eGFR). This study aimed to determine if an acute bout of moderate-intensity aerobic exercise transiently improves non-traditional biomarkers when compared to traditional biomarkers of renal health and filtration in individuals without cardiometabolic diseases. Thirty-nine participants (n = 18 men; n = 21 women; age 32.5 + 12.6 yr; height 171.1 + 11.4 cm; weight 78.7 + 15.6 kg; BMI 27.1 + 5.8) completed a single bout of moderate-intensity (50–60% HRR) aerobic exercise. Blood and urine samples were collected and compared before and post-exercise. Serum creatinine, urine epidermal growth factor (uEGF), uEGF/urine creatinine ratio (uEGFR), and cystatin C (CyC) were measured. In addition, eGFR-MDRD and the CKD-epidemiology equations were used to analyze renal clearance. Relative to pre-exercise measures: serum creatinine (p = 0.26), uEGF (p = 0.35), and uEGFR (p = 0.09) remained unchanged, whereas cystatin C (p = 0.00) significantly increased post-exercise. CyC eGFR was the only estimator of renal filtration to significantly change (p = 0.04). In conclusion, CyC is the only biomarker of renal health and filtration to significantly increase after aerobic exercise. Further investigation focused on sampling time and exercise-intensity is needed to solidify the current understanding of renal health and filtration.