Every weekend I go on a "long run". Expert trainers recommend that you do one run every week that accounts for approximately 30% of your weekly miles and since I am incapable of creating my own training plan, I listen to the expert trainers.
When I'm in training for a race, the long run can be up to 14 miles. Right now, however, I am just attempting to fend off winter weight gain and stay in relatively good shape so I've scaled back to between 7-9 miles. This is the perfect run length in my opinion. Anything less than 3-4 miles and I'm annoyed that I'm going to all the trouble of putting on my shoes. Anything longer than 10 and my body starts to reject the run and I end up miserable and dying on the side of the road. But 7-9 miles? Perfect. I could run that distance every day and be completely content.
Garmin Forerunner 305 - the greatest invention of all time and my most favorite running purchase ever. Seriously, if you have ever even considered going for a run, you should buy this thing. It's that freakin' amazing.
The Garmin Forerunner includes a heart rate monitor strap and computer software that tracks all your runs (you can even enter your indoor runs manually). I got my Garmin in June 2008. I've logged approximately 1300 miles since then (I'd say close to 1000 of those runs were outdoors with the Garmin) and the heart rate monitor battery is just now starting to die. I know that it is starting to die because as I ventured out into the cold last week, it suggested to me that my heart rate was 39 degrees. Now, I'm definitely a hypochondriac, but I know for a fact that my heart rate was not 39 because if it was, I would have been at the hospital and not preparing to run 7 miles. I gave the monitor a tug and it appeared to straighten itself out, but I'm pretty impressed that it lasted as long as it did.
The Garmin works just like its automobile unit does - the device connects to satellites and tracks distance and speed. Pretty cool - the display allows you to choose heart rate, pace, total time, time remaining, total distance, and time. You pick how many you want displayed, which ones, and where you want them displayed (which sounds kind of unnecessary, but believe me once you get used to heart rate being in one spot, you don't want distance to be in that spot all of a sudden. "What? My heart rate is 5.39?")
You can also program in different workouts. The Garmin will beep for you to speed up or slow down depending on the workout you entered. It will show you when you are ahead of pace or falling behind. And if you get lost, it will direct you back to your starting point!
I've got the Forerunner 305 and there have been some newer models released since I got mine. I'm perfectly content with mine though (and now it is cheaper because of the newer models and that's always a good thing!) The unit is a decent size (bigger than a typical sport watch), but it fits my wrist fine. It comes with a larger wrist strap along with the computer software and charging cradle. On a few occasions I've needed to update the software, but customer service has always been really helpful and the issue is typically resolved right away. The display is large enough to steal a quick glance at which is important as the alternative is squinting down at your wrist and risking getting hit by a car.
So there you go - a running essential.