What ever you can handle??? Tough question to answer, the running has to be pain free, you don't want to go back to square one. Just ease into it the first week, ultimately it all depends on your over all fitness, and what you did during your lay off from running. I went through a 5 week period where I didn't run, but to compensate I put all my time I should have been running into swimming and biking, so I was able to jump right back into the workouts for running (obviously a lot slower, but I was still able to handle the time, since my fitness still was moving forward). Just be smart, if you need to just put extra time on the bike and slowly bring your run up to speed. High bike volume makes you run faster in a 70.3 anyways!! Good luck.

When's your 70.3?
I can't give you medical advice, but the first thing I'd do is create a training plan that got me up to a long run of 15 miles following the 10% rule, see what that leads to in terms of week 1 volume, and then ask if it's reasonable.
But if your race is soon and you need to start week one with a long run of 8-10 miles, be careful.

I'm coming off of a broken ankle and subsequent knee scope...I followed Pete Pfitzengers plan to return to running:
http://www.pfitzinger.com/labreports/stressfracture.shtml
His program is labeled for after a stress fracture but as he says in the article it can be used for any injury that has kept to out for 6 to 8 weeks. I'm in week five and so far no problems, in fact my running feels better than it has in years. I've been biking about 100 a week even before I started running so I'm not off the couch.
Be advised that there are an increasing number of running coaches that think the 10% rule is dead. Your body doesn't know 10%. It knows what it knows. The current thoughts are to increase following your comfort level then hold that distance/time for two to three weeks before increasing again.
Again it will depend on when your race is and I whole heartedly agree with dk...be careful.

pain free is your guide

[quote=rachapkis]Other than the 10% rule, is there a rule about how much milage I should run in week 1?
[/quote]

I am going to let everyone in on a huge secret. The 10% rule is 100% made up. No scientific evidence what-so-ever to support it. How much you should increase from week to week is dependent on a lot of things, but the decimal (base-10) number system is not one of them. If 1000 years ago the duodecimal won out over the decimal system, we'd have the 12% rule.

If you run 5 miles your first week, do you really think a 20% increase to 6 miles would be careless? If an elite built up to 120 miles, do you think he would go to 132 miles the next week?

As for what rachapkis SHOULD run, I have no suggestion that hasn't been mentioned.

Let's be careful. The point is that small increases are better than large increases, for most people and most situations. To say the 10% rule is pure fiction just invites people to increase distances too quickly and risk injury.

[quote=dkhartung]Let's be careful. The point is that small increases are better than large increases, for most people and most situations. To say the 10% rule is pure fiction just invites people to increase distances too quickly and risk injury.[/quote]

Agreed--don't throw the baby out with the bathwater. The rule [i]qua[/i] rule may be out of vogue, but the principle behind it is still solid: "don't be an idiot when increasing mileage."

10% may or may not work for some individual situations, but it is generally a non-idiotic amount for a mileage increase.

No speedwork or tempo runs until you are done increasing mileage. Even if you remain under the magic 10% increase, increasing volume gives you the risk of injury. Adding speedwork to that volume increase multiplies that chance of injury.

[quote=TryScott][quote=rachapkis]Other than the 10% rule, is there a rule about how much milage I should run in week 1?
[/quote]

I am going to let everyone in on a huge secret. The 10% rule is 100% made up. No scientific evidence what-so-ever to support it. How much you should increase from week to week is dependent on a lot of things, but the decimal (base-10) number system is not one of them. If 1000 years ago the duodecimal won out over the decimal system, we'd have the 12% rule.

If you run 5 miles your first week, do you really think a 20% increase to 6 miles would be careless? If an elite built up to 120 miles, do you think he would go to 132 miles the next week?

As for what rachapkis SHOULD run, I have no suggestion that hasn't been mentioned.
[/quote]
Read above.
"...the 10% rule is dead."
Beat ya to it! ;p

Was it the Mayans who had base 20?

[quote=rachapkis]Thanks, all, I've enjoyed the discussion. I am going to pass on (and take the miniscule refund for) the 70.3 I signed up for in July, and use it to help pay for the 70.3 in Miami on October 30 (better late than never). I am going to follow the following hierarchy of rules: (1) if pain, stop and return to running when pain free; (2) if no pain, start with limited walk running (e.g., 3-5 miles total), and increase gradually from there; (3) speed work only after building up an acceptable milage base. I am going to implement my gradual incremental increases in base 9.7 (if there is such a thing . . . math (as with many other things) is not my strong suit) using a lunar calendar. :)

Richard[/quote]
A tough choice but a wise one. That's endurance sports!

[quote=Anton]
Read above.
"...the 10% rule is dead."
Beat ya to it! ;p

Was it the Mayans who had base 20?
[/quote]
Guilty as charged! You caught me skipping to the end without reading all the good advise given. Won't happen again boss. :)