I felt perfect yesterday. I went to the gym last night and all was normal. As I got into bed, I sneezed and kinda felt like I may be in the preliminary stages of a cold. This morning, I felt like I got hit by a bus. I have a fever, my throat hurts, my entire body aches. Literally, the bones in my hands even ache. Walking is difficult. At most, I'm 30% of my normal self. There is a 0% chance I could work out in this condition and perform decent lifts. If I had to fight another human being tomorrow, I would be fucksville. Imagine being a fighter where you fight someone who is presumably close to your level. Every inch counts, you can tough it out all you want, but if the person you're fighting is of a similar skill set to you, they will devour you in such a weakened state.