Light Conditioning Routine w/ Young Dog (1 yo)

Hi all. My pup Nina (possibly a mix but definitely large amount of APBT in her) is turning 1 year old next week, and her athletic physique is really showing now that she's losing her youthful chubby tuck (or lack thereof). Until she can perform heavy duty activities such as walking with a weighted pack or pulling a light weight sled, I'm looking for advice on a light routine that would be okay to do with her now, that is okay on her limbs and joints.

We currently work the flirtpole for about 15 to 30 minutes, then she gets to play with a makeshift springpole I just strung up for her (just her tug toy tied to a rope about 3 feet off the ground). We do this soon after I arrive home from school, from 5 to about 6 on and off with her resting and roaming on a long lead around the yard before her evening walk. However by 11 PM she's going nuts again, so we go out and work the flirtpole for another 15 minutes and tug/springpole for 10 minutes.

Just wondering what advice I could be given about exercising her so that her energy is spent in a way that is safe on her young joints, and keeps her visibly lean. She's currently 44lbs and on 3 cups of TotW/day.