Energy systems and 800m

You know, I used to think the majority of posters on here were 5k runners, as the typical insult went, "blah, blah, blah from some 18-minute runner". Of late it seems everyone is interested in the 8. For the better in my opinion.

From the textbook, which doesn't reveal the whole truth, and neither can I since I don't know it:

Race distance...

800 meters: 10% ATP-PC, 60% Glycolysis, 30% Aerobic

100/200 meters: 98% ATP-PC, 2% Glycolysis

400 meters: 40% ATP-PC, 55% Glycolysis, 5% Aerobic

Again the percentages are a little misleading since they are based on racing that distance, not the 400m split in an 800. Also, at any given time in an 800m race the percentages are shifting between the three systems.

Coe/Martin (p, 185) has the 800 as:

phosphagen 5%

Lactate 38%

Aerobic 57%

Most modern references give the aerobic contribution as roughly 60%. At maximum effort, the phosphagen system gives you roughly 7 seconds or 60 meters and the aerobic system starts being used at 12 seconds. Most of the anaerobic contribution is from the lactate system, not ATP/CP. The 50% crossover point between anaerobic and aerobic systems comes at 75-90 seconds, depending on what source you rely on.

A fair number of top 800 runners will take it out very hard for the first 60, using the ATP/CP energy, and then, unless you really hold back, you are going to use glycolytic energy for much of the first lap.

From a pure anerobic/aerobic standpoint:

The 800:

00-10: 80% An, 20%Aer

10-20: 65/35

20-30: 40/60

30-40: 40/60 as much as 35/65

40-50: 40/60 as much as 25/75

50-60: 20/80

60-120:20/80

This is from an article in middle and long distance running. This study was completed w. 153-200 800m runners.

Just an FYI, the 30% aerobic for the 800m came from Exercise Physiology (Powers and Howley) 2001 edition. 60% aerobic for the 1500m.

More specifically to the original poster, for a 2-minute effort they're going with 40% aerobic.

While the information is interesting, I'm not sure it's especially useful for determining training as different bodies respond so differently to the same stimuli. Snell may have trained 95% aerobically to Juantorena's 25% aerobic (guessing on that) and run the same 1:44-1:43. I think it's more helpful in pondering questions like, "What could El G do in the marathon?" based on knowledge of aerobic contribution, a Letsrun favorite pastime.