Chelsea manager Thomas Tuchel claimed earlier this month that the United States men's international needed to learn to trust his body again after suffering nagging injury issues, dating back to a hamstring problem sustained in last August's FA Cup Final defeat to Arsenal.
Tuchel's first game in charge took place on Jan. 27 against Wolves but Pulisic did not start a Premier League game until March 13.
However, the 22-year-old has started six of Chelsea's last eight matches across all competitions and he said: "I feel very confident in my body and my fitness level at the moment. I have played a string of games.
"I've never thought of myself as a player who is injury prone or anything. Obviously I had some time out in the past year and a bit. It is really just about taking care of my body and putting myself in the best position to be available for every single game. I feel good about that right now."
"I think maybe it did help a little bit to go away and get some games in with the national team," he said.
"I definitely always enjoy that and coming back, I felt very confident and I still feel that way. It is just about keeping up this form and help my team to win these big games."
Madrid are hopeful former Chelsea playmaker Eden Hazard will be fit to face his old club having struggled with muscular problems.
Hazard left Chelsea in 2019, the same summer Pulisic arrived from Borussia Dortmund, leading to inevitable comparisons between the two players as Pulisic was the only major signing the club could make due to a FIFA transfer ban.
Pulisic has always sought to distance himself from any similarities to Hazard but he added: "He was an incredible player at this football club, of course. He is someone I definitely looked up to. I am not comparing myself to him in any way or trying to be like him.
"I am my own player, doing my best for this club. Obviously he was a massive player for this club and obviously it is an honour to hear comparisons like that, but I still have a way to go.
"We are moving on without him. I never played with him so I only know how it is without him. I think we are in good place now. I mean we are in a semifinal of the Champions League, we have got a lot left to play for this season, so I think this team definitely has a good situation at the moment, so that's a positive."