Warming-Up Affects Performance and Lactate Distribution between Plasma and Red Blood Cells

Abstract

Warming-up (WU) is a widely used preparation for training and competition. However, little is known about the potential mechanisms of WU on performance and on the lactate distribution in the blood compartment. The purpose of the present study was to investigate whether different WU procedures affect performance and lactate distribution between plasma and red blood cells (RBCs) after maximal exercise. At three different occasions eleven subjects performed one 30 s maximal effort exercise on a cycle ergometer. Before each exercise, subjects warmed up at different intensities: 1. no WU (NWU); 2. extensive WU (EWU); 3. intensive WU (IWU). Blood samples were taken under resting conditions, after WU, and in 1 minute intervals during recovery to determine lactate concentrations [LA] in whole blood ([LA]WB), plasma ([LA]plasma) and erythrocytes ([LA]RBC). Mean power output was +58 Watt (EWU) and +60 Watt (IWU) higher compared to NWU. For each WU condition [LA]plasma and [LA]RBC differed significantly at any time point, showing greater [LA]plasma compared to [LA]RBC. The maximal effort exercise caused a rapid decrease of the [LA]RBC/[LA]plasma ratio. [LA]RBC reached the peak 3-5 minutes later than [LA]plasma depending on the WU condition. The initial increments in [LA]RBC were 10-16% lower after IWU compared to NWU and EWU. The lower increment of [LA]RBC after IWU might be due to a "higher preloading" with lactate before exercise, causing a smaller initial [LA] gradient between plasma and RBCs. It seems that the influx decreases with increasing intracellular [LA]. Another possibility one could speculate about is, that the extracellular increase in [LA] inhibits the outflux of lactate produced by the RBC itself. This inhibited export of lactate from RBCs may lead to an intracellular lactate accumulation. But the relatively fast increase in [LA]RBC and other investigations partly contradicts this possibility. Key pointsWarm-up significantly improves performance during 30 s maximal effort exercise.No differences in performance were found between extensive and intensive warm-up.Warm-up and maximal effort exercise affects the lactate distribution between plasma and RBC.Lactate influx into RBC decreases with increasing intracellular lactate concentrations.

Keywords: Lactate concentration; anaerobic exercise; blood; competition preparation; cycling; performance enhancement.

Figure 1.

Time course of the exercise protocol. Warming-up consisted of 12-min cycling at 60% VO_2peak (extensive warm-up; EWU) or included three high intensity phases of 10 s at 200% of VO_2peak (dashed lines) additionally (intensive warm-up; IWU) followed by a passive resting phase of 5 min. Afterwards subjects performed a 30 s all-out exercise. Blood samples were taken under resting conditions (R), directly after warming-up (WU), after 4 min of rest (pre), directly after exercise (0’) and in minute intervals during recovery (1’-15’). Arrows on top assign blood samples.

Figure 2.

Lactate concentrations in plasma (Pl) and in RBC of all three conditions, at rest (R), after WU (WU), after 4 min of rest (pre), and in minute intervals during recovery (0'-15'). For NWU the ’pre’ value equates the ’R’ value. NWU: squares, solid line; EWU: triangles, broken line; IWU: circles, dotted line. The white bar represents the 30 s all-out exercise.

Figure 3.

Increments (∆) of [LA]_plasma (A) and [LA]_RBC (B) in each time step. Significant differences in ∆ [LA]_plasma and ∆ [LA]_RBC were only found in the time interval (pre-0'). For NWU the ’pre’ value equates the ’R’ value. NWU: squares, solid line; EWU: triangles, broken line; IWU: circles, dotted line. *significantly different from IWU (p < 0.05). Calculated with a paired student t-Test.

Figure 4.

Changes of the ratio ([LA]_RBC/[LA]_plasma) during all three conditions, at rest (R), after WU (WU), after 4 min of rest (pre), and in minute intervals during recovery (0'-15'). For NWU the ’pre’ value equates the ’R’ value. NWU: squares, solid line; EWU: triangles, broken line; IWU: circles, dotted line. The white bar represents the 30 s all out exercise. * significantly different from NWU at respective points of time; # significantly different from EWU at respective points of time.