Role of the monocarboxylate transporter MCT1 in the uptake of lactate during active recovery.

Purpose: We assessed the role of monocarboxylate transporter 1 (MCT1) on lactate clearance during an active recovery after high-intensity exercise, by comparing genetic groups based on the T1470A (rs1049434) MCT1 polymorphism, whose influence on lactate transport has been proven.

Methods: Sixteen young male elite field hockey players participated in this study. All of them completed two 400 m maximal run tests performed on different days, followed by 40 min of active or passive recovery. Lactate samples were measured immediately after the tests, and at min 10, 20, 30 and 40 of the recoveries. Blood lactate decreases were calculated for each 10-min period. Participants were distributed into three groups according to the T1470A polymorphism (TT, TA and AA).

Results: TT group had a lower blood lactate decrease than AA group during the 10-20 min period of the active recovery (p = 0.018). This period had the highest blood lactate for the whole sample, significantly differing from the other periods (p ≤ 0.003). During the passive recovery, lactate declines were constant except for the 0-10-min period (p ≤ 0.003), suggesting that liver uptake is similar in all the genetic groups, and that the difference seen during the active recovery is mainly due to muscle lactate uptake.

Conclusions: These differences according to the polymorphic variant T1470A suggest that MCT1 affects the plasma lactate decrease during a crucial period of active recovery, where the maximal lactate amount is cleared (i.e. 10-20 min period).