I would recommend this plan for someone already running about 30 miles per week training for at least their second marathon!
For all the lifting, core and body weight (BW) exercises, I will upload separately. Yasso: run 800 in time in minutes you want to finish your race in hours (example: I want to run my next race in 3:35 hours so I will run an 800 in 3:35 minutes). For mile repeats run those at 10k pace then rest/jog/walk in between.
For hill repeats: Warm up 2 miles. Find a big hill taking 2 minutes to climb. Run half way up the hill 3-4 times and jog to bottom. Then run all the way to the top, jog to the half way point and sprint the rest of the way down. Do this 3-4 times then cool down with 2 miles easy.
*The mileage and speed work only for this plan came from Runner’s World magazine, I do not take credit for formulating this part of the plan!*