1/7/11
6 miles tempo
54:00
9:00 avg pace
Today’s tempo run called for 2 miles easy, 2 miles hard (7:54 pace), and 2 miles easy. Here’s what I did: 2 miles at 9:30 pace (easy), 2 miles at 8:00 pace (hard), 2 miles at 9:30 pace (easy). I wanted this to be a strong tempo run for me so I modified the hard pace to 8:00 instead of 7:54…nothing to lose sleep over. And I felt really good. The 8:00 pace was comfortably hard, which is what a tempo run should feel like. I did this run on the treadmill since it was snowing when I woke up. Ugh…2nd treadmill run this week. I only resort to treadmill running when it’s really cold, really dark, or snowing. I’ll take running outside over treadmill running any day, even in the rain.
So what is a tempo run? The goal of a tempo run is to improve your lactate-threshold pace. Lactate threshold is the point at which lactate starts to build up in the bloodstream because lactate production is greater than lactate clearance. Once lactate accumulates in your bloodstream, you begin to slow down. You want to improve your lactate-threshold so you are able to run at a faster pace without accumulating too much lactate. Your lactate-threshold pace should be close to the pace that you can currently race for 1 hour (source: Advanced Marathoning). For most marathoners, this is your half marathon pace. If you go faster than your lactate-threshold pace, you’ll accumulate lactate rapidly and if you go slower, you won’t be providing enough of a stimulus for improvement. You really want to narrow in on the pace where lactate is just starting to accumulate. The design of a tempo run usually consists of a warm-up and cool-down and sandwiched in between are a few miles at lactate-threshold pace.
Another great thing about tempo runs (and the reason why they are one of my favorites) is the psychological benefit. Marathons are hard and it’s so easy to give up and let your pace fall off towards the end. With tempo runs you sustain a fast pace for miles (as opposed to speed work, where you sustain a fast pace for generally less than a mile). This builds your confidence and mental toughness.
OK, enough with the science lesson. Tomorrow is a rest day for me and Sunday is a long run (13 miles). I’ll post all the details about that on Sunday along with some info on refueling (I’m sure you can’t wait :))
I’m trying to spice up my posts with pictures so, for today, I’ll leave you with a picture of Hawk playing in the snow. Warning…it’s an extreme close-up!
Ruth says
Great information, Kristy. I never knew that about lactate threshold pace.
I’d be interested to know if you ever do interval training for a marathon.
Kristy says
By interval training do you mean speed work (repeats of up to 1 mile) at 5K pace? I have in the past and for this marathon I am doing them.
Amanda says
Thanks for the science lesson. I enjoy that aspect but not enough to read literature on it. So I rely on you to share your knowledge. Hope the long run went well this morning. It’s windy out there!