2010 Fiscal Year Final Research Report

Evaluation of muscle energy metabolism during exercise for effective altitude training

Research Project

Project/Area Number	20700533
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Sports science
Research Institution	National Agency for the Advancement of Sports and Health
Principal Investigator	HOMMA Toshiyuki National Agency for the Advancement of Sports and Health, スポーツ科学研究部, 研究員 (90392703)
Project Period (FY)	2008 – 2010
Keywords	筋エネルギー代謝 / 低酸素 / 磁気共鳴分光法 / 近赤外分光法 / 無酸素的代謝 / 有酸素的代謝
Research Abstract	We investigated the differences in muscle energy metabolism during a knee extension exercise of varying intensities under conditions of normoxia and hypoxia. The values of muscle phosphocreatine (PCr), pH, and oxygen consumption (VO_<2mus>) were significantly lower at submaximal identical workloads under hypoxic conditions than at normoxic conditions (p<0.05). At exhaustion, in both the conditions, there was an almost complete depletion of the muscle PCr and no difference in the values of muscle PCr. However, the muscle pH and VO_<2mus> at exhaustion were significantly lower during hypoxic conditions than during normoxic conditions (p<0.05). The results of this study suggest that as compared to normoxic conditions, hypoxic conditions cause a decrease in the aerobic energy supply and an increase in the anaerobic energy supply in muscles during exercise at identical workloads.