Whoa, whoa, whoa...

What happened? I thought I was back to being able to deal with this climate? What happened to Monday's run when I felt like the old me? Or Wednesday when, despite feeling like crap, I was able to complete my run and do it fast? Or Thursday when I negative split the last 2-mile interval in scorching heat? Why could I not go more than 5-miles yesterday slower than molasses? This isn't how this is supposed to work. It's supposed to be different this time around. What am I supposed to do when my body can't handle this? I know I've been pushing my body, but I've been resting and eating well. We had a day of complete rest Friday. I shouldn't be feeling like this. I guess all I can do is some strides then hit the bike....