Before the Vikings boarded a plane on Tuesday night — breaking with their usual travel routine and leaving the Twin Cities two days in advance of a road game — coach Mike Zimmer took a minute on Tuesday afternoon to articulate how difficult the Vikings' assignment will be in Los Angeles. "Yes, it's a problem," Zimmer said.

"We haven't had a home game on a short week since I've been here in five years. It is what it is," Zimmer said. "We go out and play the schedule however they do it. I know the statistics about going to the West Coast on a short week and all of that. Part of the reason we are going out, we did a study on preparing for a game on a short week, all of those things. That is why we are going out tonight after practice."

What, you might ask, are the statistics? They're not favorable to teams in the Vikings' position.

Since the NFL introduced its Thursday night package in 2006, teams traveling from outside the Pacific Time zone to play on the West Coast are 1-7. The only team to win in that time was the 2012 Denver Broncos — a 13-3 team traveling one time zone west to face a 4-12 Oakland Raiders club. Teams playing Thursday night West Coast games after traveling two or more time zones are 0-6 in that time.

It's a small sample size — perhaps because the NFL tries to avoid giving teams the assignment the Vikings face on Thursday night — but teams traveling west haven't been particularly successful since 2006, no matter the time of day. In that time, teams from outside the Pacific Time zone are just 19-36 in all West Coast night games. Teams traveling two or more time zones west are 13-30 in those games.

The problem isn't jet lag so much as circadian rhythms: Because the NFL's start times are standardized for national TV, West Coast teams play their home night games at 5:20 local time, meaning their players' bodies are still functioning at a high level around the time their opponents' bodies are used to winding down for the night. Stanford researchers studying 25 years worth of Monday night games in the 1990s found West Coast teams won 63 percent of those games against East Coast teams. Since those games always started at the same time, it didn't matter whether they were on the West Coast or East Coast — the West Coast teams always outperformed their Eastern counterparts.

Associated Press, Star Tribune

The most notable example in recent Vikings memory, of course, came in 2015, when a team that harbored playoff hopes opened its season in the second half of the league's Week 1 Monday night doubleheader. The game kicked off at 9:20 Central time, and a 49ers team that many expected to be among the league's worst dominated the Vikings in a 20-3 victory. Minnesota went 11-5 and won the NFC North that season, while the 49ers finished 5-11. But that night, when the Vikings almost appeared to be sleepwalking, it was with good reason.

Zimmer loves to use historical trends like these as fuel for his team, and there's little doubt he's spent much of the week telling the Vikings how history is stacked against them on the West Coast. They'll have a chance to beat the odds on Thursday night, as they face both the NFC's only undefeated team and another opponent — their own body clocks — that's proven to be rather formidable over the years.