On March 18, 1944, a Finnish ski patrol troop was behind Russian lines when they were ambushed. They managed to escape during the ensuing firefight, but the Russian soldiers pursued the men, beginning a good old-fashioned ski chase.
Still deep in enemy territory, the odds did not look good for the fleeing Finnish. Feeling exhausted, Finnish soldier Aimo Koivunen remembered he had the whole troop's supply of Pervitin (aka methamphetamine) stored inside his pocket. This drug was given to soldiers at the time to keep them awake whilst on duty. He popped the lot, like Popeye eating a big can of spinach – he hadn't wanted to take all of them, but while being pursued in the cold it was difficult to take out an individual pill, especially while wearing mittens.
His energy was soon boosted, perhaps unsurprisingly given that he had just taken 30 times the dose of methamphetamine he was supposed to. Koivunen, leading the troop and breaking the snow for the rest of them, helped the whole pack to speed up considerably. But you can't just take an overdose that massive and expect the only side effect to be "really good at skiing". He soon began to notice that his vision was distorted, and he was losing consciousness.
The very next thing he can recall, he was 100 kilometers (62 miles) away, had no ammunition, no food, and was completely alone. Whatever happened in the interim, he had somehow lost his entire squad.
Still substantially high on speed, Koivunen got up and began to ski on through the forest by himself. His appetite had been killed by the drug, which was fortunate given the lack of food. For the next few days, he survived by eating pine buds and a small Siberian jay he'd managed to catch, completely raw.
Still under the influence, he managed to escape the Russian troops who are pursuing him, but trod on a landmine. He lay there, delirious and passing out from time to time, before realizing that no help was coming. His determination – and alarming amounts of methamphetamine in his system – got him out of the ditch and kept him going through the freezing conditions.
By the time he was found, he had traveled 400 kilometers (250 miles). In a Finnish hospital, they found his heart rate was an impressive (or alarming) 200 beats per minute, and he now weighed just 43 kilograms (94 pounds).
But he had survived, and would go on to live to 72, still unable to recall how he lost his entire troop while skiing through the forest and completely off his face on speed.