The Dogs have eight players currently on restricted duties, including key players Brian Lake and Adam Cooney with leg complaints.
Ayce Cordy, Sam Reid, Lukas Markovic and Jordan Roughead are all returning from shoulder operations, while Callan Ward and Ryan Hargrave are also in the rehab group.
The Bulldogs resume pre-season training on January 4.
"We divided them into different groups based on priorities and what we were expecting in the off-season," head of physical conditioning Bill Davoren told afl.com.au, when asked how the Dogs were approaching summer.
"A few of them have been on modified programs so they'll be gradually reintroduced into the workload.
"We're trying to make sure they're physically and mentally fresh for the long haul.
"Generally I've been pretty happy with how they have come back. We've had a pretty good week already of training and their running ability has been impressive."
The young Dogs returned to training last week and were joined by the four- to seven-year players on Thursday.
The rest of the list resumed on Monday with a five-week training block - that includes a seven-day adventure training trip to New Zealand - to look forward to.
"We're going to build until Christmas; that's the aim, to build slowly to then and we're looking at some pretty solid work during the New Zealand week and just preceding Christmas," Davoren said.
"We're going to build up so we can apply a bit of pressure around that January time ahead of the NAB Cup."
Davoren said he was very happy with the fitness of new Bulldogs Nathan Djerrkura, Justin Sherman and Patrick Veszpremi, with the former winning last week's 3.2km time trial.
He said the players now had the New Zealand training camp in their sights, which will include an eight-hour hike through Otago's mountain range, The Remarkables, and a multi-stage adventure race.
"We're going there because it's got an outstanding training facility, which gives us a really good opportunity to do everything we need to do," Davoren said.
