I don’t think this is true! Days of your life are (imo) not defined by the date line, but by the 24-hour periods you experience. If you accept my rules, then as long as you always have flights shorter than 24 hours, you can still run on sequential days.

Edit: you could also potentially run on the plane. I admit that would be pretty weird though

Will Shortz (NYT crossword editor) had a table tennis streak that was going to be affected in a similar way.

> You cannot fly from New York to Bangalore without missing a day in the calendar. So I flew to Dubai and stopped there for two and a half days, played table tennis at clubs there, and then flew on to Bangalore. I’ve been to China and Japan multiple times, and, because of the time change, the flight leaves New York at, say, 11 a.m. and gets to China or Japan late afternoon the next day. So I play early in the morning, like seven or eight, go directly to the airport, fly to Beijing, get off the plane, and go directly to a club to keep my streak alive.

https://www.newyorker.com/culture/the-new-yorker-interview/w...

A friend of mine is on a 25 year running every day streak. He flew to Australia and landed 2 days after taking off and said that day “never existed for him” ¯\_(ツ)_/¯