Run volume for Sprint/Oly training?

Hard to say what is "appropriate".  Depends upon your goals and longer-term history.  I'd want to maintain pretty similar mileage, if at all possible.  But I'd also look to keep my runs at 4x.  Add a short run off one of those bikes?

FWIW, I'm in similar situation.  I mostly do sprint tri's and I'm currently training for the Sarasota HM on 3/17.  I'm running 4 days per week, including a long run on Saturday mornings.

I've been very run-focused getting ready for the HM, to the detriment of my swimming and riding.  After I get through the HM I want to get back to a more balanced schedule, but I'm planning to stay at 4 runs per week, limiting the long run between four to six miles.

After the HM my running will look like this:

Mon: 2.0 to 3.0 mile EZ recovery run after long bike on Sunday

Tues: 3.0 miles

Thu: 3.0 miles

Sat: 4.0 - 6.0 miles

That gives me 12 to 14 miles/week ave.  I used to do everything in Z2, but have gotten away from HR training over the last couple of years and now just go by RPE.

Depending on how I'm feeling, I often make either Tue or Thu a tempo run.

Other relevant info is that I'm 59 ( will be 60 in May), have chronic patella tendinosis in my right knee and degenerative tendinosis in both Achilles.  Due to age and my infirmities I stick to a Galloway run/walk strategy, going 4:1 on a good day and down to  2:1 if I'm sore.  All my running is done in the early morning which fits well with the rest of my schedule (plus I'm a morning person).

I'm made some significant improvement with my running in the last 24 months which I primarily attribute to consistency (and the resultant higher volume), and losing 20 pounds.  I want to lose another 15 lbs this year.

HTH.

Mark

I agree with this, a couple of miles after the bike will add up soon.

FWIW I have read in the past that a multiple of 2.66 x the race distance in your weekly training is a good rule of thumb.  Not the be all end all, plus it scales pretty high for IM distance and very low for sprint's.

Personally, I would add 1 more run to the week.