Runner's Training Tips: Mission: run 50 miles a week--How much mileage is too much?

I'm 4'11, currently weight 118. My goal weights is 110 or 105. I've been running since Jan. and stoped in May and have started again in June.

 In order to add to my running mileage I've created my own routine of long runs during the week. My questions is the mileage too high? I'd like to get to  50 miles a week and stick with that. I always rest once or twice a week.

This week:

Sun. 6.99      M. 4.34      Tu. 5.29      Th. 8      F. 8      Sat. 10            Total: 42.62 miles

Next week:

M. 10       Tu. 8             W. 10              Th. 6                Sat 13                Total: 47 miles

Week of July 26:

Sun. 6.5              M. 5        Tu. 10       Th. 10        F. 5.5      Sat. 13         Total: 50 miles

REST WEEK:

Sun. 5               M. 3           Tu. 5        Th. 4          F. 3         Sat. 5           Total: 25 miles

Basically after this I'd go back to the 50 mile per week schedule on July 26th (maybe mix up the miles and adding to my Sat. long run) and replace it with the rest week at the end of each month. Eventually I'd like to run a race, but I don't have time at the moment, so I thought running this for myself in hopes of finding a race after summer would be motivation enough. 

 Thanks so much for reading this, I appreciate it.

As rpe says ... 10% increase is a good guide for increasing mileage. If you add in more run days to the week you should keep the mileage the same.

Remember that quality is better than quantity. You're not really giving any details of how hard you're doing these runs e.g lactic threshold, intervals or ? If they're all easy runs it's probably not going to be too bad, but you may get more benefit with harder runs on days before a rest day. 

My critical thinking on your schedule is: 

1) I think the 5 days per week with two rest days looks good.

2) I'm not sure that you'll get the full benefit from your 'rest week'. While the mileage is less, it doesn't seem much of a rest as you're still running 5 days of it. I'd be tempted to put Mon & Fri runs into Tues & Sat respectively. Thereby giving you more rest days and a schedule that looks like:

Sun. 5     Mon rest    Tu. 8  Wed rest   Th. 4      F rest          Sat. 8           Total: 25 miles

If you're really getting into your running those short 3 milers are hardly worth getting your kit on for.

3) Looking at your "This week" schedule I think you'd be better off swapping Tues & Fri mileage around. That way you get mid, short, long, rest, long, short, long rather than mid, short, short, rest, long, long, long. It becomes better balanced like your week 3 schedule.

 All in all though, looks like you've got a good plan.

I can remember reading an article in Runners World, back in the mid 1990s, that came to the conclusion that there was no significant difference between runners who did 39 miles per week, and those who did 50.

P.S. to EVERYONE: I'll post up new mileage with my old stuff and pace. So far, its easy runs. Very chillaxed type of running. I sweat a lot and when the humidity is up there (I'm from DC), I don't exert myself to often...

Hope this helps until I can post an update.