Strange was relegated to 18th man for Sunday's 22-18 loss to the Bulldogs, which left Canberra in 10th spot with five rounds to play.
Stuart revealed afterwards he told Strange several weeks ago he needed a week off at some point, with the 19-year-old having played every minute of his rookie season.
The playmaker was then given time to return home to Sydney early in the week, before Adam Cook started in his place at Belmore against the Bulldogs.
"I see the physicality he is copping as a 19-year-old boy who has played every minute of the season," Stuart said.
"I have to look after him, because I feel in the back end of the season he will be better for the team.
"He wasn't happy with it at all. He's not a kid who wanted to shy away from playing.
"But I have to worry about Ethan for the back end of the season and how he starts it next year.
"I know how to look after young players. When you have so many in your squad, it is important for me to show some welfare to the physical side of it as well."
Strange's rest was largely facilitated by Jamal Fogarty's return a fortnight ago against the Warriors.
Canberra have the toughest run home of any team in finals contention, and likely need to win four of their last five to make finals.
But with Fogarty back, Stuart is adamant that is possible, insistent the halfback's three-month absence through a biceps rupture had been largely overlooked by critics.
"You don't hear about what happens down in Canberra, but we have had Jamal and Hosko (Zac Hosking) out for three months," Stuart said.
"Jamal is an unbelievable loss in our football team. He is as much of a loss as Nathan (Cleary) is to Penrith or (Adam) Reynolds to Brisbane.
"You guys don't write that or say that. I get that, he's not as high profile. But he wins or loses games for us.
"You can see the performance and quality of our play has gone up with Jamal in our team again."
Stuart also suggested Corey Horsburgh was an option to play his first NRL game since round five against the Sea Eagles on Saturday, with Morgan Smithies suffering a concussion at Belmore.
Hosking also suffered a shoulder injury, with Emre Guler, Peter Hola, Simi Sasagi and Ata Mariota other options to come in for Hosking and Smithies.
Horsburgh has played two games back in NSW Cup since returning from a ban, and could be headed to St George Illawarra or the Dolphins next year after requesting a release from the Raiders.
