An excerpt from a related article from the same website:
And making the low-budget movie meant long hours and, as the title suggests, a lot of running. “Run Lola Run” finds its 20-something protagonist in a race against the clock to help her boyfriend replace a drug dealer’s bag of money that he lost. Most movie stars would sign up for a few triathlons or employ Usain Bolt’s trainer to get ready for such a gig. Not Potente.
“I didn’t do any preparation really,” she admits. “I was probably smoking two packs of cigarettes a day at that point. And I was doing all this running — I was running in rehearsals, I was running when we shot all the different takes, and I would run again so we could get the sound right. I was carried along by all this energy.”