I am new to running and really enjoy it... in the evening. I would prefer to jog in the morning to speed up my metabolism, but my legs are tired from the start, making me start out at a slow crawl. On the other hand when I jog in the evening I feel like I can keep jogging forever and it's a lot more enjoyable. I currently don't do any stretching before jogging (or after for that matter) and thought maybe it would help. Or possibly a more intense warmup would get rid of the tiredness in my legs because it goes away once I've been jogging for a while. Any suggestions?