I second ECUXCTF's comments about hard days in summer and track work with HS athletes. The girls on the HS team I coach do basic distance for the first weeks back after their post-track break, focusing on building mileage back up and getting back into a routine. After several wks or so, we eventually transition into a type of surge interval (e.g. sets of 4 min at LT, 3-4 min jog) that we run at the park and a hill day that involves running a 10-12 minute hill loop for 30-40 minutes overall. In time, the surge interval gets reduced rest and faster tempo, and eventually becomes a more traditional interval workout, and the hills turn into fartlek and then shorter interval – but none of that happens until the season begins. Overall, we do 5-6 days a week during the summer, depending on age/experience, etc., and work up to 2 relatively hard days by the start of the season and one long run day (longest run by late Aug might be 65-75 minutes for our older, more advanced V-girls). Hope that helps.