Pacing your races and training for that.
After watching the Finnish Nationals and lots of other competitions I need to jump in with my point of view about pacing the races.
Honestly the experience who has made the biggest impact on me was 100 free girls and women at nationals. It is a race which should be pretty simple to swim well with an average of 1.5-1.6 sec slower second 50 m than first 50 m. But in very many cases the result was almost 3 seconds difference.
We have to work on changing that because of the following facts from best swimming nations and swimmers:
100 free average 1.5-1.6 sec. – ex. 28.0+29.5=57.5
100 back average 1 sec. – ex. 30.0+31.0=1.01.0
100 fly average 3.2 sec. – ex. 29.0+32.2=1.01.2
100 breast average 3.0 sec. – ex. 30.0+33.0=1.03.0
200 free 1.5-1.7 sec. from first to rest – ex 27.0+28.5+28.5+28.5=1.52.5
200 back 1.2 sec. from first to rest – ex. 30.5+31.7+31.7+31.7=2.05.6
200 fly 3.5 sec. from first to rest – ex. 30.0+33.5+33.5+33.5=2.10.5
200 breast 3.0 sec. from first to rest – ex. 31.0+34.0+34.0+34.0=2.13.0
Of course there can be small changes from individual to individual.
If you are more towards a 200+ swimmer then your split in 100 races can have a shorter difference. Like Michael Phelps.
If you are more a 50 m swimmer there can be a little bigger gab between first and second 50 m.
But in general you have to experiment through the year and through the prelims, semi and finals so you also practice your ability to execute process goals.
The better lactate tolerance you have the harder you can swim the race with out loosing your stroke, because you have trained that ability. But you need a good aerobic capacity to be able to achieve a good anaerobic capacity. There is no easy way to achieve the perfect split.
During trainings a lot of neg. split work in your mind in most sets is bringing you there easier I even though can promise you.
If you are fly and breaststroker it can be better to swim ex. 10×100 start every 2-3 min and swim 50 free + 50 fly or breast there with turn from fly/breast. There you can practice your speed of second to fourth 50 in your 200 m.
Last 50 in 100 can be practiced in many ways but needs the turn to be included. To achieve the right speed you might need to swim first 50 building up the speed to the turn and then keep it home from there with a strong turn.
In any kind of race the first 25% of the race needs to be used the smallest effort and frequency, the second 25% moving up to what you can take the rest of the way and then the last 50% keep it there. Ex. Free 48-50-51-51 in a 100 meter.
Also in stroke counting the difference from first 50% to last 50% needs to be small. Phelps has as ex. often 17 strokes out in 100 fly and 19 back. Working on making it 16+18. What is the hard part here is then the length under water after the turn needs to be longer than most of you are used to do, but that just takes practice:=).
Good luck with best possible pacing in the future