This winter I'm competing on my HS swim team and want to stay in decent running shape for outdoor track. My focus has previously been on the 800m and mile, and I want to continue running the 8, so some aerobic running on top of swimming will be necessary. Teammates of mine seem to have developed pretty decent aerobic bases off swimming alone, so I'm not too worried abut that. However, I also feel l have above average (but undeveloped) speed and, with some extra muscle from swimming, will also consider running the 400m. So my winter running will need to consist of speed training and some light aerobic running. The goal is to a) keep up an aerobic base; b) keep my body "used to running"; and c) develop speed.
I'll have about 45mins to train every morning Monday-Friday and as much time as I need on weekends. I'm thinking along the lines of starting each day with a strength/core session (pushups and crunches and stuff) and maybe two or three easy miles. Probably doable in 45mins, and not hard enough to be worn out the rest of the day. On weekends I'll focus on speed and longer runs. So a week would look like:
Mon-Fri: 20min core circuit, easy 3 miles
Sat: easy 5-8 miles, strides
Sun: weights, hills, stadium stairs, flat sprints, etc.
So, is this a good plan for staying in running shape through swim season? Or am I way overthinking this and should just go for a run every now and then?
Also, if the core circuit thing is a good idea, what could that include?