Albion head to Anfield on Monday night and although Mulumbu succumbed to a knee problem during the African Cup of Nations with DR Congo recently, the midfielder feels he should be ready to take on the Reds.
"I missed the QPR FA Cup game before the African Cup of Nations with what I thought was a small injury," he said.
"But the intensity of the games in the African Cup of Nations meant I needed a rest when I came back.
"It was hard mentally and physically but I've had a good rest over the last week and I feel refreshed.
"Mentally it was hard not to get through the group and it was quite painful physically playing through the injury.
"But when you play for your country and fans you just get over it - and I did it.
"I have been training this week but today was my first day back training with all the team.
"I think I will be fit for Monday's game, my knee is getting better, and I felt really good today."