Main Set Monday - Pace Pace Pace

Are you a swimmer who operates like a vacuum cleaner, with one speed and a very simple ON/OFF switch?  Or are you a swimmer who operates more like a high-tech piece of stereo equipment, with an infinitely variable volume control and multiple dials to control your treble, bass, and high-frequency output?   This set favors the high-tech piece of equipment.

WARMUP:  400

WARMUP SET:  300
This set will get you accustomed to changing gears.  
Swim twice through:
2 X 25 freestyle w/ max of 2 breaths per 25.  Count your strokes to get your "N."
2 X 25 freestyle, breathe as much as you want but take 2 fewer strokes (N minus 2).
2 X 25 freestyle, breathe as much as you want but take 2 additional strokes (N plus 2).

MAIN SET:  1750
Swim seven rounds of the following:
1 X 200 choice (do the same thing on each 200 so you can compare your times)
1 X 50 active recovery

Goal:  Descend your time by 4 seconds on each 200.

This set is all about pace!  You will be rewarded if you hold back and swim at a controlled aerobic pace on the first two 200s.  The idea is to increase your level of effort throughout the set, up to 85-95% effort on the final 200.  Don't worry about your sendoff/turnaround.  After each 200, pause long enough to get your time, then push off for a 50 of active recovery.  After the 50, you can take anywhere from 10 to 50 seconds rest before you start the next 200.  The goal is to hit your descends, not to make a particular turnaround.    Here's an example of how the set would look for someone who wants to hit 2:30 on the final 200:
#1:  2:54
#2:  2:50
#3:  2:46
#4:  2:42
#5:  2:38
#6:  2:34
#7:  2:30

Beginner swimmers can do a modified version of the set:
Five rounds of the following:
1 X 100
1 X 50 active recovery
Descend time by 2-3 seconds on each 100.

WARMDOWN:  200 easy