800s - What do they mean?

One year ago at this time I was training for marathon #2 and a possible BQ attempt - 3:15. On Tuesday, the 19th of October, 2010, I ran 8x800 intervals on a mostly flat greenway. My times then were 3:07, 3:01, 3:02, 3:03, 3:08, 3:05, 3:08, 3:04, 3:03. My marathon time (and current PR) was 3:15:13.

Today I am near the end of my training for marathon #3 and a possible sub-3 attempt. Goal pace runs throughout the summer and fall have been tough, but target reached. My intervals have been sporadic at best. I often felt too sore or tired to do well on them. Tempo runs have also been a struggle and usually turn into short marathon pace runs instead of reaching 10k pace.

The schedule for today was 8x800s. Last week was a cut back week and I skipped Monday's easy run, so I felt pretty well rested. I went to a local college track before work. The inner lanes were blocked with high hurdles and the public is only supposed to be on the outer lanes. So I set my Garmin to do the measuring for me: .5 mile interval with .25 mile rest - repeat 8 times with a warm up and cool down.

I did an easy 1 mile warmup and then hit the lap button to start. I did not look at my pace as I ran, just wanted to see how the first one went. Running the outside lanes is kind of nice because a half-mile is less than 2 full laps. That seemed to help mentally.

The Garmin does a countdown beep about 3 or 4 seconds before you reach the end of an interval. Actually it is probably based on distance. Interval number one: 2:52.

Based on the Yasso 800 principle if you can do 800s (half-miles) in x minutes, you can do a marathon in x hours. I was aiming for 3:00 halves. I thought, "Not bad, but can I do this 7 more times?"

Quarter-mile rest (less than one full lap unfortunately) - beeping countdown to start - GO! I figured I could back off a little and try to conserve, but somehow came in slightly faster: 2:51.

I only looked at my watch after each interval. In fact I had the screen showing the last lap pace and time of day. I was looking for anything at or under a 6:00 pace for the last lap. I could easily divide by 2 to get the actual time. Or more easily, divide the difference from the seconds and 60 by 2. For example, if the Garmin showed a pace of 5:42 as it did for that interval, I subtracted 42 from 60 = 18/2 = 9. 3:00 - :09 = 2:51. And I was able to do that during my quarter mile rest distance, which were typically about 2 minutes long. However it wasn't easy to count on my fingers while running. "Oops! Watch out for that hurdle!"

Round and round I went, starting with the beeps, ending with more beeps. To make a long story short my times came to (including ones mentioned above) 2:52, 2:51, 2:53, 2:56, 2:55, 2:56, 3:00, 2:55 (last one - push it). Here is the Garmin report.

Supposedly this indicates a sub-3 hour marathon. I reckon I shall find out on November 12 in Richmond.