Many years ago, as a fanatical distance runner in my late teens in Auckland, New Zealand, I witnessed a highly unusual event. It was during the
cross-country season, and the favorite for the senior men’s 12-kilometer event, Mike Whelan, arrived in the parking lot a few minutes before the
start of the race. He had, it turned out, got the start time of the race wrong. As he raced across the field tearing off his tracksuit and jamming his spikes on his feet, the gun went off while he was still 300 meters from the start line. As he passed through the start line, the other runners were disappearing up a hill at the far end of the field.
He doesn’t have a prayer of winning, I thought. Yet, incredibly, even after giving up over a minute handicap to the rest of the field, he still came
in first. What was even more amazing was that he won by his usual winning margin of that season—over a minute—with no warm-up. Since then I’ve had the occasional race where I was late for an 8K or 10K, arriving only a few minutes before the start time, and run my usual time for 8K or 10K without the benefit of a warm-up. Many other
stories abound about how records were set by athletes in different sports without a warm-up.

How Dehydration Affects Running Performance
There’s insurmountable amount of research evidence demonstrating that the more weight you lose from perspiration during a race or competition, the more drastically your running performance declines. The rate you lose water depends on a variety of factors including individual sweat
rate (which is highly variable), air temperature, humidity, and length and intensity of your running. How much sweat can we lose during a race or
training effort? Lots! Losses of over 1 liter had the occasional race where I was late for an 8K or 10K, arriving only a few minutes before the start time, and run my usual time for 8K or 10K without the benefit of a warm-up. Many other stories abound about how records were set by athletes in different sports without a warm-up.