The Reebok Stadium boss has been without the likes of Stuart Holden, Chung-Yong Lee, Sam Ricketts and Marcos Alonso due to long-term problems.
Jussi Jaaskelainen also missed the 5-1 defeat to Chelsea prior to the international break, although the goalkeeper is expected to return to the first XI for Saturday's trip to Wigan.
During their battle with a length injury list, Bolton have taken just three points from seven matches to slump to the foot of the table, following six successive defeats.
But Coyle is not going to push people back to fitness, as he told a press conference broadcast on Sky Sports News: "They are certainly improving.
"That augers well. But we can't be rushing anybody back.
"We have to make sure first and foremost that when they come back it is the right time for them to continue their careers, as much as we would love them fit and available now."
Jaaskelainen returned to training on Tuesday and Coyle is hopeful the experienced shot-stopper will not suffer any adverse reaction following his thigh problem.