Non-oxidative Energy Supply Correlates with Lactate Transport and Removal in Trained Rowers

Area of Science:

• Exercise Physiology
• Sports Science
• Biochemistry

Background:

• Understanding energy metabolism during high-intensity exercise is crucial for optimizing athletic performance.
• The role of non-oxidative energy supply and lactate dynamics in trained athletes requires further investigation.

Purpose of the Study:

• To investigate the association between non-oxidative energy supply, muscle lactate accumulation, and lactate removal capacity in elite rowers.
• To explore the relationship between monocarboxylate transporter content and these physiological parameters.

Main Methods:

• Seventeen trained rowers performed a 3-minute all-out rowing ergometer test to determine accumulated oxygen deficit.
• Blood lactate levels were measured during passive recovery to analyze lactate accumulation and removal rates using a bi-exponential model.
• Muscle biopsies were analyzed for monocarboxylate transporter (MCT1, MCT4) content and citrate synthase activity.

Main Results:

• Accumulated oxygen deficit positively correlated with net muscle lactate release, MCT1 and MCT4 content, and lactate removal velocity (γ2).
• Lactate removal velocity (γ2) and exercise lactate release rate were negatively associated with citrate synthase activity.
• These findings indicate a link between energy supply capacity and lactate handling during intense exercise.

Conclusions:

• The capacity for non-oxidative energy provision during supramaximal rowing is interconnected with muscle lactate accumulation and transport.
• Lactate removal ability during recovery is also associated with the non-oxidative energy supply during intense exercise in trained rowers.