Training Hikes, Anyone?

What do you do to either stay in hiking shape or to get into hiking shape? Do you do training hikes or do you spend time at the gym on the treadmill or stairmaster?
With the heat of summer coming pretty quickly, most of my training is at the gym. I do quite a bit of cardio work on the treadmill by doing interval training. I try to do this 2-3 days per week. I also try to do strength training 1-2 days per week.
When we have cooler weather, I try to do an overnight hike at least once a month, along with the workouts at the gym. I've got a big hike planned for next year, so I am slowly increasing the intensity of my workouts so as to build up my endurance levels.
I am curious as to what others do as far as staying in shape.
UL

I'm a little bit of a weirdo when it comes to working out. I strength train 6 days of the week, and usually try to run 2-4 miles 3-4 times a week. I don't have a ton of time to hike right now, but I can always spare a few hours to work out.

willky:
I used to do a lot more strength training than what I do now. About three years ago, I started training more for endurance than strength and have noticed a big difference in my ability to cover more ground in a day of hiking than before.
Now, I concentrate on intense treadmill workouts, with the incline set up to 10-15% and walking speeds up to 4 mph. This is about as close as you can get to replicating climbing the hilly terrain around here. I typically do this for up to an hour at a time.
My strength training now is more high reps (15-25 reps) and lighter weight (50-60% of max) for 3-5 sets. This allows me to continue to tear down muscle tissue and rebuild, but it also helps to build the muscle endurance that I am looking for. You won't get as big doing this, but you will last longer out on the mountains.
UL

Oh, yeah. You definantely have a better "hiking" work out. Muscle endurance is huge. I used to do something that me and some buddies called "quick weights". We would do 3-4 sets, but the sets were a little different. We would do as many reps as we could for 15 sec, take a 5 sec rest holding the weight up (for example, on bench press we would hold the bar up in the air), and then do as many reps as we could for 15 more secs. That would be one set. You do this with very low weight, and should be about to exhaustion by the end of the 3rd or 4th set. This did a lot for muscle endurance, but I hated it. Guess thats why they call it a WORKout.

I used to race off-road motorcycles. A common saying in that circle was "any workout is better than nothing."

We spent as much time riding as we could, but any time we could spend in the gym was nearly as valuable. Particularly in the off-season.

I mostly try to maintain core strength through free-weight strength training and some cardio. I'm not as consistent as I used to be and it shows in my ability to hike.

There's some honesty for you boys. Hate to admit it, but I don't spend enough time in my gym. That's a fact.