I have been running 4 to 5 miles a day this last week.Checked my pace .It was like mid 6 s or7 minutes a miles.I am about 15 pounds or so over my running weight.Current weight 165 and i am 5 10 and 1/2.My fitness in 2013 March was 15 30 .I will be 43 December 14 this year.How do i work my way back and how long will it take?