TY - JOUR
T1 - The impact of intermittent exercise in a hypoxic environment on redox status and cardiac troponin release in the serum of well-trained marathon runners
AU - Li, Feifei
AU - Nie, Jinlei
AU - Lu, Yifan
AU - TONG, Tom K K
AU - Yi, Longyan
AU - Yan, Huiping
AU - FU, Frank H K
AU - Ma, Shengxia
N1 - Funding Information:
This study is fully supported by the Dr. Stephen Hui Research Centre for Physical Recreation and Wellness at Hong Kong Baptist University, and the Key Laboratory of Exercise Stress and the Adaptation and Hypoxic Training Centre at Beijing Sport University. Part of the financial support for publication is from a research grant from the Fundamental Research Funds for the Central Universities of China (No. 2015ZD001). No conflicts of interest, financial or otherwise, are declared by the authors.
Funding Information:
Acknowledgments This study is fully supported by the Dr. Stephen Hui Research Centre for Physical Recreation and Wellness at Hong Kong Baptist University, and the Key Laboratory of Exercise Stress and the Adaptation and Hypoxic Training Centre at Beijing Sport University. Part of the financial support for publication is from a research grant from the Fundamental Research Funds for the Central Universities of China (No. 2015ZD001).
PY - 2016/10/1
Y1 - 2016/10/1
N2 - Purpose: To investigate the effects of hypoxic training on redox status and cardiac troponin (cTn) release after intermittent exercise. Method: Nine well-trained male marathon runners (age, 21.7 ± 2.3 year; body mass, 64.7 ± 4.8 kg; height, 177.9 ± 3.8 cm; and VO2max, 64.3 ± 6.7 ml kg−1 min−1) completed intermittent exercise under normoxic [trial N; fraction of inspiration oxygen (FIO2), 21.0 %] and hypoxic (trial H; FIO2, 14.4 %) conditions in random order. Each bout of intermittent exercise included hard run (16.2 ± 0.8 km h−1) at 90 % VO2max for 2 min followed by easy run (9.0 ± 0.4 km h−1) at 50 % VO2max for 2 min and 23 bouts in 92 min totally. Malondialdehyde, reduced glutathione (GSH), superoxide dismutase, an estimate of total antioxidant capacity (T-AOC), high-sensitivity cardiac troponin T (hs-cTnT), and cardiac troponin I (cTnI) were measured before, immediately after (0 h), and 2, 4, and 24 h after the completion of trials N and H. Result: GSH was increased immediately after trial N. T-AOC was lower 4 h after trial H than trial N. Hs-cTnT was elevated from 0 to 4 h and returned to baseline 24 h after both trials. CTnI was increased after trial H; peaked at 2–4 h and returned to below the detection by 24 h. Conclusion: The overall redox status was balanced under normoxic conditions, and exercise-induced cTn release did not deviate. However, the protective effects of antioxidant were weaker in the hypoxic state than normoxic, and the stress on the myocardium induced by intermittent exercise was transiently aggravated.
AB - Purpose: To investigate the effects of hypoxic training on redox status and cardiac troponin (cTn) release after intermittent exercise. Method: Nine well-trained male marathon runners (age, 21.7 ± 2.3 year; body mass, 64.7 ± 4.8 kg; height, 177.9 ± 3.8 cm; and VO2max, 64.3 ± 6.7 ml kg−1 min−1) completed intermittent exercise under normoxic [trial N; fraction of inspiration oxygen (FIO2), 21.0 %] and hypoxic (trial H; FIO2, 14.4 %) conditions in random order. Each bout of intermittent exercise included hard run (16.2 ± 0.8 km h−1) at 90 % VO2max for 2 min followed by easy run (9.0 ± 0.4 km h−1) at 50 % VO2max for 2 min and 23 bouts in 92 min totally. Malondialdehyde, reduced glutathione (GSH), superoxide dismutase, an estimate of total antioxidant capacity (T-AOC), high-sensitivity cardiac troponin T (hs-cTnT), and cardiac troponin I (cTnI) were measured before, immediately after (0 h), and 2, 4, and 24 h after the completion of trials N and H. Result: GSH was increased immediately after trial N. T-AOC was lower 4 h after trial H than trial N. Hs-cTnT was elevated from 0 to 4 h and returned to baseline 24 h after both trials. CTnI was increased after trial H; peaked at 2–4 h and returned to below the detection by 24 h. Conclusion: The overall redox status was balanced under normoxic conditions, and exercise-induced cTn release did not deviate. However, the protective effects of antioxidant were weaker in the hypoxic state than normoxic, and the stress on the myocardium induced by intermittent exercise was transiently aggravated.
KW - Cardiac troponin
KW - Exercise
KW - Hypoxia
KW - Oxidative stress
KW - Redox
UR - http://www.scopus.com/inward/record.url?scp=84984612185&partnerID=8YFLogxK
U2 - 10.1007/s00421-016-3460-5
DO - 10.1007/s00421-016-3460-5
M3 - Journal article
C2 - 27572505
AN - SCOPUS:84984612185
SN - 1439-6319
VL - 116
SP - 2045
EP - 2051
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
IS - 10
ER -
