Mark Warburton said that the international break was used wisely to manage the upcoming schedule ahead of the trip to Birmingham on Saturday.
Several of the first-team squad represented their countries during the last two weeks and Warburton knows they have to manage the players' workload accordingly.
He said: "We have used the break for a combination of things. We have given the boys some time off, made them work hard before the time off and we hope the international players returned fit and well.
"The boys were back this morning with no major injury worries so fingers crossed for the weekend.
"There has been a lot of work done by the medical and sports science guys. You have to check the loading on each player; some have gone away and played no minutes, while some have played three or four games. Daryl Murphy and Jamie Ward have played in intense games and we have to assess it and liaise with our counterparts with the international sides.
"It is about doing the right thing by each player and if we can get that right, then fantastic."
The Forest boss is expecting a tough encounter when they make the trip to St Andrew's despite The Blues' lowly league position.
"It will be a difficult challenge," he said. "They have had a tough run of results, which we had earlier in the season, so I would imagine the management team have worked hard on strengthening their unity and togetherness.
"They will be very keen to make the right impression in front of their own fans and we have to be prepared for that.
"They have some very talented individual players, are a strong outfit who are hurting a little bit at the moment and will be keen to rectify that so we know what we face."