Lactate acts as an acid buffer and is formed when pyruvate stores excess hydrogen ions, rather than causing fatigue.

“with lactate comes hydrogen and hydrogen reduces the ph and that reduction in ph with that hydrogen ion makes it very difficult for the actin and myosin filaments in the muscle to release and that's what people are actually experiencing when they feel that horrible burn that's actually erroneously attributed to lactate it's really the hydrogen ion”

“And it's that hydrogen that actually paralyzes the actin meosin filaments prevents them from disengaging and that's what leads to that seizing up that you feel the rigidity you feel when you're at and when you exceed your lactate threshold.”