[OPTICAL REVIEW Vol. 10, No. 5 (2003) 436-439]
© 2003 The Optical Society of Japan
Relationships between Changes in Oxygenation during Exercise and Recovery in Trained Athletes
Eiji YAMADA*, Takashi KUSAKA1, Kensaku MIYAMOTO2, Satoshi TANAKA, Shin MORITA, Shouichi TANAKA, Yongping CAO2, Satoshi MORI2, Hiromichi NORIMATSU2 and Susumu ITOH3
Department of Rehabilitation, Kagawa Medical University Hospital, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
1Maternal Perinatal Center, Kagawa Medical University Hospital, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
2Department of Orthopedic Surgery, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
3Department of Pediatrics, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
(Received February 13, 2003; Accepted June 5, 2003)
The purpose of this study was to investigate the relationships of rate of deoxygenation determined using near-infrared spectroscopy (NIRS) during isometric contraction exercise (Ratedeoxy) with maximal muscle strength, muscle thickness and muscle oxidative capacity of knee extensors in eight well-trained male athletes. The subjects performed sustained isometric extension at 30% and 50% of the maximal voluntary contraction (MVC) load for 10 s and 30 repetitive maximal isokinetic knee extensions. Ratedeoxy in the final 5 s of 30% MVC was negatively correlated with maximal muscle strength, muscle thickness of knee extensors and the half-time of deoxygenation recovery (T1/2) determined by NIRS after 30 repetitive maximal isokinetic contractions, defined as muscle oxidative capacity. The results suggest that Ratedeoxy during submaximal isometric contraction reflects muscle aerobic capacity.
Key words: near-infrared spectroscopy, deoxygenation rate, isometric contraction, maximal muscle strength, muscle thickness, oxidative capacity
*Corresponding author. E-mail address: yamada@kms.ac.jp