Abstract
A study was undertaken to evaluate the effect of aerobic training on lactate oxidative capacity during aerobic exercise using [U-14C] lactate. Male ddY mice were trained by means of treadmill running 5 days a week for 6 weeks. [U-14C] lactate was injected after the first 5 min of running at a speed of 30m⋅min-1. The mice then continued to run for another 25 min at the same speed. Expired gas was collected to estimate the amount of 14CO2 expired during the exercise. The amount of [14C] lactate expired as 14CO2 during the first 10 min after injection of [14C] lactate was significantly higher in the trained group (T) than in the control group (C) . The blood lactate concentration, and muscle lactate concentration in the soleus immediately after exercise were significantly lower in T than in C. The muscle glycogen and blood glucose concentrations were higher in T than in C. It is concluded that aerobic training in mice decreases the blood lactate concentration during exercise, and also enhances oxidative removal of lactate.
