I can only really advise what has finally worked for me after 7+ years struggling to get any real exercise. Thing had gotten worse and worse, be it shin splint, knee problems, the darn hips and even my heart/breathing.
I had abandoned cycling(knees) for walking then later abandoned walking up hills, but the pains just got worse.
I did get back to some cycling by spinning the pedals faster than normal. But only when I was, by chance, forced to walk too fast for a train did I guess the walking was far far worse than cycling.(it resulted in days of really intense hip pain)
Realisation dawned but it took a full 12 months for my severe shin pain to go, and about the same for the hips to near fully recover.
The trick it seems, is, no matter what exercise you do, keep everything as near to zero impact as you can. Thus I have easy gears on my bike and done right I can even keep my knees working.