Which is Better? 3×300 or 2×350 Speed Endurance Workouts?

Last Updated on March 28, 2010 by Jimson Lee

Which is better? A 3x300m or 2x350m speed endurance workout for your 400m sprinter?

The short answer is… it depends.

For a sprinter on a long-to-short program, a 3x300m is effective because the athlete will probably be running at near, but not equal to the 400m “race pace speed”.  It also depends on the recovery.  I’ve seen this workout performed with recovery times of 10-20 minutes between runs. 

For a sprinter on a short-to-long program, a 2x350m is effective as long as they are running at race pace speed.  However, I feel this distance is too far for non-elite sprinters, and a 2x325m is more realistic, or even 2x300m for youth athletes.

I’ll explain my rationale below.  To simplify things, I’ll be subtracting 1 full second for acceleration out of the blocks.   All runs in the workout are “on the fly” or using a 10 meter running start.

Hypothetical Example

Let’s assume we have a sprinter with PBs of 11.5 & 23.0 for 100m/200m respectively, and wishes to run 50.0 for 400m.

23 sec = (1 + 22)  or a running of speed of 9.09 m/s (see the 150m workout guidelines)

A 23 sec 200m PB calculates splits of 24 and 26 for the 400m.  Run the first 200 1 sec slower than your 200m PB, then the next 200 2 sec slower.  You are probably familiar with the equation “doubled your best 200 plus 4 seconds” (some argue it’s double plus 3.5 seconds, but that’s another story)

When you look at a 200m 23 sec PB, it could translate to splits of 11.5 + 11.5, which is actually (1 +10.5) + 11.5 (thus a slowdown of 1.0 over the second half… 11.5 minus 10.5).  This is normal.

Of course, compare MJ 1996 WR of 19.32 = 10.1 + 9.2 = (1 + 9.1) + 9.2 means he barely slowed down!

In the 400m, 50 seconds translates to:

• 50 = (1 + 49) or 8.2 m/s (note the difference in 9.09 m/s above)
• 50 = 24 +26
• 50 = (1 + 23) +26
• 50 = 1 + (11.5 + 11.5) + (12.5 + 13.5)

NOTE: see how the 300m split is actually 35.5 fly or 36.5 with blocks?

3 x 300? or 2 x 350m?

So if you are planning a 3x300m workout, ideally the splits would be 35.5 on the fly assuming full recovery.  That 3rd set will hurt like hell, trust me.  But often, I’ve seen them run slightly slower, say 36-mid range (approx. one second slower), because there’s not enough recovery.  The shorter the recovery, the slower the run.  This is often the case for long-to-short workouts, and the goal of this workout is more lactate tolerance and mental toughness.

Also, note how depressing that 13 point last 100m split looks! … but what do you expect carrying a bear, elephant and piano on your back?

I feel you should NOT go past 40 sec to work on speed endurance (type II), thus a  2 x 40 sec workout is my ultimate goal, assuming proper form and relaxation throughout.

2 x 350 meters is too much distance for non-elite 400m sprinters because the athlete in this example would split 42.25 fly or 43.25 with blocks.  Thus 325 meters is more ideal… aiming splits of 38.9 fly or 39.9 with blocks.  With a WR of 43.18, Michael Johnson could easily run sub-40 sec for 350 meters!  You are not Michael Johnson, and neither am I.

For a youth sprinter, I would not go past 300m.  Keep the “distance” at 40 seconds.

But before one attempts to run 3x325m on a short to long program, try 2×250 first, then work your way up.  Accurate hash marks of 250, 280, 300, 310, 325 meters are easily found on the track… just ask any 400 meter hurdler!  Only when have reached the desired split time should you increase the distance.  That may take an entire training season!

Of course, a 50 sec hand time is really 50.24, so as a coach sitting in the stands, I want to see at least a 49.7 hand time to ensure he (or she!) breaks 50 FAT!  I’ve run 49.8 HT only to see a 50.08 FAT show up in the results.  Bummer.

I’ll discuss a modified workout for indoors in the next article.