Effect of the Long Term 'Training and Competitive' Cycle on Renal Function, Oxidative Stress-Derived DNA and Muscle Damage in Elite Triathletes of Malaysia

Strenuous exercise may cause DNA, renal, skeletal and cardiac muscle damage. Triathletes experience strenuous muscular activity both during training and competition, risking tissue damage. There is no literature that describes the cumulative effect of ''training and competition" cycles over a season of triathlon competitions. The objective of this study was to assess the cumulative effect of "training and competition" on renal function using urine protein and creatinine in male triathletes and to estimate DNA, skeletal, and cardiac muscle damage using blood biomarkers, 8-hydroxy-2'-deoxyguanosine (8-OHdG), myoglobin, and cardiac troponin I (cTnI) among both male and female triathletes. Seven male and seven female triathletes were recruited in this study. They were on a standardized training regime and participated in at least one endurance event every month for the past 3-4 years (Male: 4.14 ± 1.57, Female: 3.29 ± 1.70). They were followed up over 10 months. Samples of urine and blood were collected at the start (Phase 1) and end (Phase 2) of the triathlon season. Urinary protein and creatinine levels were measured u_sing spectrophotometry while serum biomarkers were measured using enzyme-linked immunosorbent assay. Samples were compared using Student's t test (where p<0.05 was considered significant). There was a statistically significant difference in urinary protein and creatinine levels (p<0.05) between Phase 1 and Phase 2 of the study among the male triathletes. Male and female triathletes showed statistically significant increases in 8-OHdG. A similar increase was observed with serum myoglobin, but it was not statistically significant in both sexes. cTnI levels showed no changes in both sexes. This study showed that there was a double increase in urinary protein and creatinine at the end of the "training and competition" cycle for an elite triathlete. There could thus be increased evidence of DNA damage among triathletes. However, no similar effects were observed with the skeletal and cardiac muscle biomarkers. This study demonstrates the cumulative effect of training and competition over a period of 10 months season with respect to renal and DNA damage in triathletes.

Senaman yang berat boleh menyebabkan kerosakan pada DNA, ginjal, otot rangka dan otot jantung. Triatlet mengalami aktiviti otot yang berat semasa Latihan dan pertandingan, mengakibatkan risiko mengalami kerosakan tisu. Belum ada mana- mana makalah yang menghuraikan kesan kumulatifkitaran "latihan dan pertandingan" sepanjang satu musim pertandingan triatlon. Objektif kajian ini adalah untuk menilai kesan kumulatif "latihan dan pertandingan" terhadap fungsi ginjal menggunakan protein dan kreatinin dari urin pada triatlet lelaki dan mengkaji kerosakan DNA, otot rangka, dan otot jantung menggunakan penanda biologi darah, 8-hidrosil-2'- deoksiguanosin (8-OHdG), mioglobin, dan cardiac troponin I ( cTnl) pada triathlet lelaki dan wanita. Tujuh triatlet lelaki dan tujuh triathlet wanita direkrut untuk kajian ini. Mereka mengikuti latihan yang standard dan bertanding dalam sekurang- kurangnya satu acara setiap bulan bagi 3-4 tahun terakhir (Lelaki: 4.14 ± 1.57, Perempuan: 3.29 ± 1.70). Mereka dipantau selama sepuluh bulan. Sampel urin dan darah dikumpul pada awal (Fasa 1) dan akhir (Fasa 2) musim triatlon. Aras protein dan kreatinin urin diukur menggunakan kaedah spektrofotometri manakala penanda biologi serum diukur menggunakan enzyme-linked immunoso_rbent assay. Sampel dibandingkan menggunakan Student 's t test (p <0.05 dianggap signifikan). Didapati terdapat perbezaan yang signifikan secara statistik dalam protein dan kreatinin urin (p <0. 05) di antara Fasa 1 dan Fasa 2 di kalangan triatlet lelaki. Kedua-dua triatlet lelaki dan wanita menunjukkan peningkatan yang signifikan secara statistik bagi aras 8- OHdG. Corak peningkatan yang serupa dilihat dengan mioglobin serum triatlet lelaki dan wanita, tetapi di dapati ianya tidak signifikan secara st-atistik. Tahap cTnl tidak menunjukkan perubahan bagi kedua-dua jantina. Kajian menunjukkan terdapat peningkatan dua kali ganda protein dan kreatinin urin pada akhir kitaran "latihan dan pertandingan" triatlete. Kebarangkalian terdapat peningkatan bukti kerosakan DNA di antara triatlet wujud. Walaubagaimanapun, kesan serupa tidak terdapat pada penanda biologi otot rangka dan jantung. Penemuan ini memberikan bukti kesan kumulatif musim latihan dan pertandingan sepanjang IO bulan untuk kejadian kerosakan ginjal dan DNA di kalangan triatlet