I am quite interested in using weights to strengthen my core.
What do you know about it, I work out all the time myself.
I prefer free weights for toning arms and back.
I do almost everything with barbell right now.
I also use a rowing machine on my lunch hour.
That is smart, it is good to do something active to break it up.
Rowing inside is preferable given the outside temperature 
Yeah no kidding, we are in the middle of a huge heat wave right now.
No rain and excessive heat makes it so hard to exercise outdoors
You are exactly right it is unbearable.