When your cells undergo lactic acid fermentation due to a lack of oxygen, it results in a significant alteration in how your muscles generate energy. Under normal conditions, muscles rely on aerobic respiration to produce energy (ATP) efficiently, using oxygen to convert glucose into ATP and byproducts like carbon dioxide and water.
However, when oxygen levels drop, the body shifts from aerobic respiration to anaerobic processes, primarily lactic acid fermentation. This method is faster but much less efficient, producing only 2 ATP molecules per glucose molecule compared to approximately 36 ATP molecules via aerobic respiration. Consequently, this reduced ATP production leads to a decrease in the energy available for muscle contraction.
Additionally, the accumulation of lactic acid in the muscles can lead to increased acidity (lower pH), which interferes with various biochemical processes crucial for muscle function. This acidic environment can hinder enzyme activity and disrupt the contractile function of muscle fibers, ultimately leading to muscle fatigue and a decrease in performance.
In summary, when oxygen is insufficient, the body’s reliance on inefficient energy production, coupled with the negative effects of lactic acid buildup, results in decreased muscle function and increased fatigue.