INFLUENCE OF RUNNING SPEED AND EXERCISE DURATION ON BLOOD GLUCOSE THRESHOLD DURING LONG-DISTANCE RUNNING

作者：Nakamura Kazuteru^*; Sengoku Yasuo; Nakagaki Kohei; Yoshioka Toshitsugu; Ogata Hitomi; Nabekura Yoshiharu

来源：Japanese Journal of Physical Fitness and Sports Medicine, 2010, 59(1): 119-130.

DOI：10.7600/jspfsm.59.119

• blood glucose metabolism
• carbohydrate oxidation
• exercise performance

This study was intended to clarify 1) the difference of the exercise intensity at blood lactate threshold (LT) and blood glucose threshold (GT), 2) the effect of exercise duration on the LT and GT during two sets of incremental running test. Ten male runners (age 25.0 +/- 3.2 yr, height 171.2 +/- 5.5 cm, body mass 57.9 +/- 4.0 kg, (V) over dotO(2max) 64.6 +/- 3.0 ml/kg/min) completed two sets of incremental running test (each set was set to run ten stages at 60-90% (V) over dotO(2max)). Second set was repeated after 8 min recovery. LT and GT speed were investigated at the first set. Lactate minimum (LM) and glucose minimum (GM) speed were selected where the blood lactate and glucose concentration were at the lowest during the second set. Using the indirect calorimetry ((V) over dotO(2), (V) over dotCO(2)), fat and carbohydrate oxidation rates were calculated. GT was observed in all runners. (V) over dotO(2) and energy expenditure were similar between the two incremental running tests, however, fat oxidation was significantly higher and carbohydrate oxidation was significantly lower during the first half of the second set. This change was regarded as the influence of the exercise duration in the first set. Furthermore, GM speed was significantly lower than GT speed, but LM speed and LT speed were not different. It was considered that the shift of GT was affected by the substrate utilization change during prolonged exercise. (Jpn. J. Phys. Fitness Sports Med. 2010, 59 :119 similar to 130)

• 出版日期2010-2