A Cristiano Ronaldo brace, as well as goals from Javier Hernandez, James Rodriguez and Isco, eased Real to a 5-0 thrashing of Levante on Saturday.
The win at Estadio Ciudad de Valencia represented Real's seventh victory in a row in all competitions - a run that has seen them rack up 32 goals in the process.
Ancelotti's side are in ominous form ahead of a week that sees them travel to Liverpool in the UEFA Champions League on Wednesday and host Barcelona in the season's first Clasico three days later.
And the Italian feels hard work on the training ground is the reason behind his team's recent upturn.
"We're on a good run but we have to remember that behind the goals is sacrifice, hard work and concentration," he said in quotes reported by AS.
"There are no goals without sacrifice and concentration. The best understand that. We’ve come here in good physical and mental condition.
"The players have shown they are a very competitive squad. Physically they're all good and they're motivated.
"The pace of the team was good and the players have all done very well."
Ancelotti went on to laud Ronaldo, who has now scored an incredible 15 goals in seven La Liga outings this season.
"What he does is impossible," he added.
"He has to continue with his condition and we will help to keep it that way."
