Base building and interval training?

I have a couple of questions for you knowledgeable ladies:

1. How long does one need to work on building a base? I'm not coming from the couch, I have been hiking, snowshoeing, weight lifting and going to aerobics classes for years. I started cycling last year. Running has been off and on, never more than a 5k, I'm working on slowly increasing my distance now. But I've never done anything close to a structured training program. Since I got my hrm, I've discovered I actually enjoy running if I keep to an easy zone 1 - 2. However I'm itching to start some interval work. I've been doing the slow runs for about 6 weeks now, can I start doing intervals yet?

2. If the guideline is to do intervals once a week, does that mean I do one run interval workout AND one bike interval workout? Or do I have to pick one, either run OR bike, for the week?

Thanks!

It sounds like you could start doing intervals.
I do my run intervals and my bike intervals on the same day. Cluster the hard work together. It was hard at first, but it works and it did not take me long to adjust.

I started out moderately with my interval training and stuck to a slow and steady increase of intensity and duration.
For example, if I was scheduled to do 4 repeats the first week, I stuck to four even if I felt like I could do more. Taking it slowly has allowed me to progress without injury(knock wood). Some days it was hard to hold back, but it was worth it.

So perhaps start with a warm -up, 30 second pick-ups with a min recovery , do 4 and then cool down. Or something along those lines.

I am sure the big guns will chime in with some good advice.

Ruth

Yes, you should be ready to run some intervals. You can do one interval workout of each discipline in a week and like RnR said, cluster them if you can. If you're not doing a lot of workouts you might want to do them on consecutive days, like tues run and wed bike. Save the long stuff for the weekend.

I cluster my week like this:

Mon: light swim and yoga/strength workout
Tues: hard run - intervals and med length bike at low intensity but not recovery (ie 20 to 60 min of solid zone 2)
Wed: hard/long swim and recovery bike
Thurs: hard hill ride, hitting zone 4 and 5, solid zone 2 run
Fri: recovery ride and light swim with short fast intervals for speed form
Sat: Long ride, run or brick
Sun: Long ride or run

The big thing to note is that I have my hard workouts 3 days in a row and I position easy days on either side of those to allow for adequate recovery. It is just as important to plan for recovery as it is to plan for intervals.

Hope this helps.