Anaerobic threshold, skeletal muscle enzymes and fiber composition in young female cross-country skiers

Acta Physiol Scand. 1980 Mar;108(3):263-8. doi: 10.1111/j.1748-1716.1980.tb06532.x.

Abstract

Anaerobic threshold (AT) and maximum oxygen uptake (max VO2) were determined in 15 young female cross-country skiers, aged 15--20 years, during incremental bycycle ergometer exercise. Succinate dehydrogenase (SDH), malate dehydrogenase (MDH), citrate synthase (CS) and lactate dehydrogenase (LDH) were analyzed biochemically and percentage of slow twitch fibres (%ST fibres, myosin adenosine triphosphatase staining) histochemically in muscle samples obtained from m. vastus lateralis. Max VO2 correlated significantly with anaerobic threshold in ml x kg-1 x min-1 (mlAT) but when AT was expressed in percent of max VO2 (%AT) the correlation was insignificant. Significant correlations were found between %AT and SDH (r = 0.63) and between mlAT and CS (r = 0.58). Max VO2 showed no significant correlations with the enzymes studied or %ST fibres. The results of the study seem to support the hypothesis that anaerobic threshold is related to oxidative capacity of muscle.

MeSH terms

  • Adolescent
  • Adult
  • Citrate (si)-Synthase / metabolism*
  • Female
  • Humans
  • L-Lactate Dehydrogenase / metabolism
  • Lactates / blood
  • Malate Dehydrogenase / metabolism
  • Muscles / enzymology*
  • Oxidoreductases / metabolism*
  • Oxo-Acid-Lyases / metabolism*
  • Physical Endurance
  • Physical Exertion
  • Respiration*
  • Sports Medicine*
  • Succinate Dehydrogenase / metabolism

Substances

  • Lactates
  • Oxidoreductases
  • L-Lactate Dehydrogenase
  • Malate Dehydrogenase
  • Succinate Dehydrogenase
  • Citrate (si)-Synthase
  • Oxo-Acid-Lyases