If there is one training principle I have come to both love and hate, it's the negative split. It's also one of the most important.
In short, it means that you increase effort and, thus (hopefully) speed, on the second half of your workout or race. Workouts can also be gradual in increasing effort, resulting in descending time so it is some times called descending workouts or intervals (ie. in swimming, you can do a set at descend 1-2-3, which means you descend time over the next three intervals). No matter what you start at one pace, but you end up at increased pace/effort.
Our bodies race like we train. When we go all out during a race, we often put out the most effort and have the highest speed during the first part of the race, when we're fresh. Then when the second half of the race comes, we find ourselves getting more and more tired and often slow down as we hit the finish line.
This is bad! Slowing down as you approach the finish line, often starting from miles out, means:
1. You're getting tired and depleted. Maintaining speed becomes a grinding experience or impossible. Your heart rate starts leaping higher and higher and you have no choice but to slow down or else you'll flame out...or pass out.
2. Your better trained opponents are now passing you. That sucks right? You try to pick it up and you can't!
3. As you get depleted, your muscles get stiffer and stiffer as lactic acid builds up. It just becomes a painful experience as you force your muscles to keep going, and you may be reduced to walking, or weak spinning for cycling, or for swimming your stroke rate just keeps dropping as your arms feel like lead.
4. Mentally, it just makes the race feel like the worst experience ever. You're glad to hit the finish line and you wonder why in the world did you ever subject your body to that kind of torture.
However, training via negative splits or descending intervals means you condition your body to be able to perform while tired and give more energy during the latter half of the race. You learn to pace yourself and not go all out in the beginning, and your body learns to give that extra kick in second half while your energy levels begin to wane.
In every workout I do, I try to always finish with more effort than I begin. I slowly ramp effort and speed throughout a workout and then by the end of the workout, I am sprinting towards the parking lot where my car is. Or I'm on the way home on my bike and after doing laps on Kings Mountain, I'll raise my energy level pedaling and get close to sprinting home on the bike.
It's a tough workout, but over time your body gets used to it. Come race day, you'll be thankful for training this way. During races you're always putting out 100%+ effort and you need to be conditioned to give extra effort even while your energy level is dropping.
What a rush to be accelerating and passing other competitors and feel like a million bucks as you accelerate towards the finish line!
