The Old Trafford side beat Newcastle United in the League Cup final on Sunday to lift a major trophy for the first time since the 2017 Europa League.
"Of course, yesterday the players were still enthusiastic and they had to celebrate this momentum," Ten Hag told reporters ahead of Wednesday's fifth-round Cup tie against West Ham.
"But yesterday, after we settled down, we get back to work. What we had to do was recovery and the ones who played less (in the final) did a good training session.
"Nothing beyond, eh? Get back to work!"
Ten Hag, who joined United from Ajax Amsterdam last year, had been under pressure when they lost their first two games of the season but the Dutchman said the key was not to panic.
"I know from experience of previous jobs it takes time before you get into a way of playing, before you get into the rules of principles," he said.
"The right results weren't there at the start of the season. I didn't panic because it was part of the process. You find out a lot in those weeks - when you lose it's not nice, you hate to lose but you also get some good lessons."
United will again be without Anthony Martial who remains sidelined with a hip injury. The French forward has made only 14 appearances in all competitions this season, scoring six times.
Luke Shaw and Fred are also doubtful while midfielders Donny van de Beek (knee) and Christian Eriksen (ankle) are long-term absentees.
Ten Hag said they would not be distracted by their Premier League clash at Liverpool on Sunday.
"I think every game is important. Every game until now, this dressing-room had the right attitude and right approach by taking it game by game and not looking ahead," he said.
"You said it's the biggest game, but is Barcelona (in the Europa League playoff) not a big game?"
