When to add weight bearing exercise with stress reaction

Today's episode comes from a YouTube viewer who posted a question, 
 
“I have a low risk grade stress reaction in my posterior tibia. Interestingly, there is some research discussing the benefits of weight bearing bone building exercise once tolerated pain free, like hops jumps and step ups. Do you have any advice on when and how to integrate these types of exercises into a rehabilitation program?” 
 
When is it okay to add weight bearing exercises when you've had a bone injury like a stress reaction? 
 
That is what we are talking about today on the Doc On The Run Podcast.