When it comes to adding speed to your run, there are a few things you can do at home. Training on a treadmill with a lot of speed variation and running uphill in short, fast bursts are two that are highly effective. But if you want to really add some intensity to your speed workout, you're going to have to hit the pool.

Swimming offers an array of benefits beyond building your speed. It's one of the most effective forms of exercise, due to the fact that it requires you to use so many muscles at once. It's also great for burning fat, reducing cholesterol, improving heart function, and combating stress.

When it comes to building your running speed, XTERRA Planet fitness coach Cody Waite prescribes the following routine:

WARM-UP
300-600 easy, mixed stroke
4-8x 50 kick w/o fins (25 fast/25 easy)
4-6x 50 (25 skull/25 swim fast)

MAIN SET
6-8x 50 @ FAST!, 0:30 rests
4x 50 one arm swim drill (25 right/25 left)
4-6x 50 @ FASTER!!, 1:00 rests
4x 50 one arm swim drill (25 right/25 left)
2-4x 50 @ FASTEST!!!, 1:30 rests
100 easy

STRENGTH SET
4-8x 100 pull, moderate, :15 rests

WARM-DOWN
100-200 easy, choice

It is common for people who aren't used to swimming regularly to worry that hundreds of yards of swimming is too difficult for them, but the truth is that people actually tend to build their endurance for distance swimming rather quickly.

If you need to build your endurance a bit before tackling the routine above, start out by swimming 50 yards, then taking a few minute break. Then increase to 100, then 150, and so forth until you can swim at least 300 yards without stopping.

You'll be surprised at how quickly you see results.