The Mayo Clinic has credible info on causes and treatment
https://www.mayoclinic.org/diseases-conditions/stress-fractures/diagnosis-treatment/drc-20354063
My ‘expert’ armchair analysis says there are three factors:
1. The initial cause could be because of over exuberance getting into super shape and overdoing it. Youth seldom knows proper limits unless they have the patience and drive to research progressive training strategies and more importantly when enough is enough. Male hormones and competitiveness factor into this big time.
2. Proper Nutrition needed to maintain healthy bones.
3. Not being patient enough to completely heal before resuming physical activity and then not slowly phasing in that activity.
Best of luck
“Dr.” RSbob