a couple of questions about running

[.Alex.]

So I'm at school and trying to fit some running into my schedule.

1) What, if any, are the effects of running with a backpack on? It wouldn't be very heavy with no more than a book and a couple of notebooks.

2) What, if any, are the effects of running in cold weather (25 - 35 degrees)? Is there anything I should consider wearing in these elements aside from long pants and a hoodie?

Apologies if these are stupid and/or obvious. Thanks!