I work at a Greyhound race track. So my job involves running in the hot sun everyday up to 4-5 hrs, literal running. We have hardly any breaks at all. Most of the time 1-2 at the most lasting only 15 minutes. The night before, I didn't get any sleep. It's not that I was up. It's that I wasn't able to fall asleep. So an entire night without any sleep. 2 hr's before work, I am dead tired, and I feel weak, and I call out. If I had something like a desk-job, or some other job with very little activity involved I wouldn't have called out. I thought it would be bad if I had gone into work and wasn't able to focus. I figured if I wasn't able to focus well because I was tired, I could have seriously screwed up, like loading one of the Greyhounds into the wrong racing box, or not noticing smaller details, like a dog possibly limping. Did I make a appropriate choice? Should I have done something differently? Like load up on caffeine or something? I've only called out twice, 1st time, due to a injury on the job, and now this time. This has been nagging at me because I am trying to be a good employee and this is something I have never called out for. Past jobs I have worked at, I would have just gone in if I was tired, but considering I have a lot of running to do at this job, and have to notice small detail, I was afraid I wouldn't be able to preform at 110%.