Whenever I start a long run, for the first 1-2, I almost always feel as if I'm running out of breath, and my heart burns. But after that, it's all easy....for the next 6-8 miles my heart rate goes back down and I feel very relaxed/comfortable for the rest of the run.
And I don't start off fast and slow down, I keep a consistent pace throughout the entire run.
Does anybody else here experience this initial pain at the start of their runs?