High intensity exercise affects diurnal variation of some biological markers in trained subjects

Int J Sports Med. 2012 Nov;33(11):886-91. doi: 10.1055/s-0032-1301887. Epub 2012 Jul 12.

Abstract

The study investigated if markers of muscle injury and antioxidant status were affected by a Wingate test performed at 2 different times of day. 15 young male footballers performed 2 tests (randomized) at 07:00-h and 17:00-h. Fasting blood samples were collected before and 3 min after each test for assessment of markers of muscle injury and antioxidant status. Resting oral temperature was recorded during each session. Peak power (10.76 ± 1.05 vs. 11.15 ± 0.83 W.kg( - 1)) and fatigue index (0.41 ± 0.04 vs. 0.49 ± 0.13%) during the Wingate test, and core temperature, were significantly higher (all p<0.05) in the evening. Markers of muscle injury were significantly higher in the evening before and after exercise (e. g., 148.7 ± 67.05 vs. 195 ± 74.6 and 191.6 ± 79.52 vs. 263.6 ± 96.06 IU.L (- 1), respectively, for creatine kinase; both p<0.001). Antioxidant parameters increased after the Wingate test but only resting values were significantly higher in the morning (e. g., 1.33 ± 0.19 vs. 1.19 ± 0.14 µmol.L (- 1) for total antioxidant status; p<0.05). The results indicate that muscle injury and antioxidant activity after the Wingate test were higher in the evening, suggesting a possible link between the biochemical measures and the diurnal fluctuation of anaerobic performance. However, repetition of this study after prescribed rather than self-selected exercise intensity is recommended.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Antioxidants / metabolism*
  • Athletes
  • Athletic Performance / physiology
  • Bicycling / physiology*
  • Biomarkers / metabolism
  • Body Temperature
  • Circadian Rhythm / physiology*
  • Exercise Test
  • Humans
  • Male
  • Muscle Fatigue / physiology
  • Muscle, Skeletal / injuries*
  • Muscle, Skeletal / physiology
  • Soccer
  • Time Factors

Substances

  • Antioxidants
  • Biomarkers