Date of Graduation

8-2016

Document Type

Thesis

Degree Name

Master of Science in Kinesiology (MS)

Degree Level

Graduate

Department

Health, Human Performance and Recreation

Advisor/Mentor

McDermott, Brendon P.

Committee Member

Ganio, Matthew S.

Second Committee Member

Kavouras, Stavros A.

Keywords

Health and environmental sciences; Cycling; Endurance; Heat; Observing; Renal

Abstract

AIM: To observe the effects of endurance cycling in the heat on renal function, and determine if the extent of impairment is related to hydration. METHODS: 40 cyclists (34 male, 6 female, 52 ± 9 y, 21.7 ± 6.5 % body fat) completed an endurance cycling event (5.7 ± 1.2 hours) in the heat (33.2 ± 5.0ºC, 38.4 ± 10.7% RH). Body mass was assessed to determine net fluid loss, muscle damage in the legs was assessed with a pain scale, a urine sample was collected to analyze hydration status, and a blood sample was drawn. All measurements were taken pre- and post-event. Serum creatinine was measured by colorimetric assay and analyzed via the Jaffe reaction, and creatinine clearance was estimated. An ELISA kit was used to measure serum neutrophil gelatinase-associated lipocalin. RESULTS: A net fluid loss of 1.3 ± 1.1 kg was observed. Urine specific gravity (P < 0.001) and leg muscle pain (P < 0.001) increased post-event. Serum creatinine increased from pre- (0.52 ± 0.14 mg/dL) to post-event (0.88 ± 0.21 mg/dL; P < 0.001). Creatinine clearance decreased from pre- (160.9 ± 48.9 mL/min) to post-event (95.2 ± 28.1 mL/min; P < 0.001). Serum neutrophil gelatinase-associated lipocalin increased from pre- (68.51 ± 17.54) to post-event (139.12 ± 36.52; P < 0.001) CONCLUSION: Changes observed in renal measures suggest acute kidney injury and reduced kidney function after endurance cycling in the heat.

Share

COinS