Its freezing outside where i live in Saskatoon, Sk Canada, and i have a sore back so i cant do alot of running and stuff for basketball… its loosening up now tho, i feel maybe i could do some running on the spot in my room for like lets say… 30-40 minutes or so…would that be good for cardio? give me your insights.
Why not do rope jumping? Far better IMO.
I run in place in the mornings before work… I’d prefer to jump rope but I have a low ceiling (in the basement). So I save it for the gym.
Running in place seems to work. I also jump like I was skipping rope (hand movements included) 
Add some body-weight squats (Tabata style) and I get a pretty good wake me up.
Whenever I’ve run in place, I’ve always felt alot more pressure on my knees. I think it’s due to a fairly straight up and down motion, versus outdoor running where the force is dissipated as you move forward.
If jumping rope isn’t an option, I’d throw together a circuit of burpees, jumping jacks, and shadow boxing. Maybe 10-15 “reps” each done for time, or 30 seconds of each done for time. That should be plenty of work to crank your heart rate and burn some calories.