I still find the first 10-15 minutes or so of every run really hard work, legs feel like dead weights, just want to give up, usually get a stitch at some point in those first 15 minutes too..... and then at some magical point, everything has warmed up, body feels okay, brain is enjoying itself and by the end of the run I feel great - tired but great. Am still amazed at how much I want to get out and do the runs despite how I feel at first. The post-run high is just fantastic!
Anyway, just needed to convey my amazement to someone!
Happy running everyone xx