Benteke has played 44 games this term for club and country, having made the move to the Premier League from Genk last summer.
He again impressed in Saturday's 3-1 victory over Stoke City, scoring the final goal to take his Premier League tally for the season to 15.
The 22-year-old Belgian now has a chance to become the first Villa player to score 20 league goals in a season since Peter Withe 32 years ago, and Lambert has no concerns about fatigue.
"Benteke was brilliant for us again against Stoke, he was up there on his own," said Lambert.
"He played for Genk before our season started, he's played every game for the national team , and then played for ourselves. He's been absolutely fantastic."
"But he doesn't look tired at all. The big guy has been terrific."
Benteke's performances this season have seen him linked with a big-money move elsewhere at the end of the season, but reports on Tuesday suggest he will start talks this week over a lucrative new contract to keep him at Villa - provided they stay in the Premier League.