system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do muscles tend to feel rubbery, unresponsive and numb for a day or so after particularly strenuous exercise before becoming sore?
gpt
When you do a work out, the muscles that are being worked develop tiny microscopic tears in them. Then, they begin to fill these gaps with new muscle tissue, which is how your muscles get bigger over time. The soreness is from these tears, and the numbness is likely fatigue from the workout, or lactic acid build up.