I am trying to get back into the swing of things after an injury, and taking this slow. The injury is not presenting any challenges. I have been able to jog at a steady pace for 5/6 miles keeping my heart rate around 150-160, after about 6 weeks of training. The time is takes me to complete the run is significantly slower than pre injury (varies from 12 to 14 minute miles). A little frustrating to have gotten so unfit. Would like to adventually run a half marathon. How much training time should go into the slow and steady to get a foundation in and when do you start different training techniques?