Pacing during your race is a matter of strategy, mainly in the middle distance events and above

Most coaches would say that to win a race, it’s a vital component for success. An athlete who goes out too hard and you’ll blow it in the final phase of the race. Or going out to slow and too far back in the pack, you can never gain on the leaders

At high level competition of the Olympics or World Championship, it’s the person who paces well will win, as the difference being a podium winner and a nobody is less than 1 per cent

Most athletes usually learn the pace via their own. You learn it the hard way most of the time. Basically the school of thoughts of pacing are of these three

Fast start

It has been researched that such fast start usually produced the worst performance

Slow start

Athletes were told to delay the heaviest effort as late in the run as possible, conserving energy at the start

Even pacing

If you’re going at an even pacing, it has been shown to produce the fastest time

A 1993 study which studied the effects of different pacing strategies. It showed that the difference between the slowest time-trial (the very slow start) and the fastest trial (even-pace throughout) was 4.3%. It concluded that even pacing was the best strategy for middle-distance athletic events

Of course although the studies have shown that a steady even pace is recommended, it doesn’t really ensure a sure-win, its just that you’ve a higher chances of winning the race. Exceptions like Hisham El Guerrouj, a runner with fast aggressive front-running likes to wins his races that way

Basically to win a race, it is the first athlete to cross the finish line, rather than the athletes with the fastest time

An example of a perfect even-paced race
Dave Wottle, USA is 1972 Olympics 800m champion
I timed him first lap 52.8sec, last lap around 53 seconds