The draining physical effects of long flights and travelling through time zones is something many of us know all too well.
So spare a thought for Belgian tennis player Elise Mertens, who made a mad dash from the WTA Finals in Texas to the Billie Jean King Cup Finals in Glasgow.
Mertens, 26, won the doubles title alongside Veronika Kudermetova in Fort Worth on Monday night.
Not even 24 hours later, after three flights and going through six time zones, she arrived in Scotland at 21:47 GMT on Tuesday night
She was not ready to play in the singles on Wednesday morning and, in her absence, Belgium lost both matches without their highest-ranked player as Slovakia clinched the best-of-three tie.