The question title is fairly self-explanatory. I used to be moderately fit because I cycled to the office, but two years of home working has seen my fitness levels plummet. I recently injured my back quite badly doing nothing of any particular note and the doctor said it was likely due to my low fitness levels, and that I needed to start exercising again to work my core.
I'm aware there are a lot of low-impact exercises I can do that target the core, but I figured it was about time I started some aerobic exercise, too. So: which is likely to be best for my all-around and core fitness: cycling or jogging?