I'm asking this here, as I'm sure the answer I'll get on other message boards is 'all that matters is calories in vs. calories out'- which I consider useless 'advice'.

Background:
I swim. I do low carb, but I don't count. About the only 'processed' foods I eat are bacon and the occasional rye cracker. I'm not losing a lot of inches lately, but I'd guesstimate I'm about 30lbs away from what I'd consider to be my ideal weight (despite being 5'6", my doc does NOT want me going below 150), and I've heard closer you are to goal, less you lose.

Now- swimming. I love it. I grew up with a pool. And while I don't necessarily think that excessive cardio is needed or natural, the fact is, I really enjoy swimming, and find intense exercise relieves stress.

But I also want to add in some running. Haven't been running for years. Started working my way back in- I wear heels virtually all the time, so my legs need to be reconditioned first. Goal is 30 min at a 5-6mph pace. Best shape of my life involved me swimming and running.

I swim for 40-50 minutes. I aim for 500m front crawl, then 500m of kicking with short fins, 500m of dolphin kick with short fins, 500m crawl w hand paddles, 500m crawl with hand paddles and buoy. Swimming is considerd aerobic, but adding in the paddles and fins really makes it more than just aerobic. I feel it in my thighs, I feel it in my arms and back. I never get my heart rate as high swimming as I do running, and running is always more of a cardio-respiratory workout than swimming.

So my question is, if I start adding in running 4-5 days a week, and I'm swimming 5-6 days a week, is that really too much 'cardio', and do I really need to do additional strength training? I'd like to slim down, but I'm not really worried about it, nor do I have a timeline. Part of me thinks an hour and a half of cardio on a regular basis is unnecessary- that wanting to do it for no other reason than to do it makes me as silly as the gym bunnies who get on an elliptical for an hour, then the treadmill for a half hour...

Any advice?

I can't imagine the logistics of running 4-5 days a week on top of 5-6 days of swimming. Even triathletes don't train like that on a regular basis. I have run and swim together at the exclusion of resistance training, and it didn't work out well for me. I was training for an aquathlon (run swim race) that I had to cancel. Swimming puts pressure on your abs and core and running does nothing to help strengthen those areas. I ended up with a very weak core (and got injured pretty bad).

I keep seeing people who overexercise with aerobic activity stalling out. I'd concentrate more on resistance training and less on the "hamster wheeling" stuff.

Overexercising causes you to create a lot of cortisol which will stop the weight loss.