Whether you’re new to exercise or have been in the game for a while, the term “lactic acid” has probably made its way into your ear a time or two. According to the Cleveland Clinic, lactic acid is a byproduct your body creates when it breaks down carbohydrates for fuel. During low-impact workouts, your body can easily filter out this byproduct through the liver and kidneys.
However, it’s not as efficient when you’re pushing yourself to the max, and lactic acid can build up. Chrissy Carroll, RRCA Running Coach at Snacking in Sneakers, explained to Verywell Fit (via Orthopedic & Sports Medicine Center of Oregon), “This is often termed “lactate threshold” for high-intensity aerobic activities (like running), but keep in mind lactate accumulation can also occur with strength training.” When a person reaches their threshold, lactic acid accumulates, it can cause various symptoms, including muscle soreness and cramping. Too much lactic acid can turn your body acidic, called “lactic acidosis.” This causes nausea, vomiting, exhaustion, and fatigue (per WebMD).
Lowering the intensity of your program and building up your max slowly can help to ensure lactic acidosis doesn’t happen. For example, it might be helpful to add breaks into your workout, vary the intensity of your workouts, use less weight, or go shorter distances. If you experience lactic acidosis from exercising, once the lactic acid is purged, it starts functioning properly again.