The 46-year-old Australian star, who is best known for his role in Gladiator, said that he has been doing lots of "sweaty" workouts in a bid to combat his weight "issue".
Crowe wrote on his Twitter page this morning: "Today Body movement 1hr, 50 min walk,14km bike ride.body movement can be anything as long as your heart rates up & you're breathing deeply (sic)."
Yesterday, he revealed that he had done two separate workouts that made him "sweaty" and the previous day, he said that he was quite surprised that he had "no residual soreness" from doing an 8km walk.
Crowe has also encouraged his followers on the microblogging site to "join the Riley St gym", telling them: "Just start, that's the hardest bit, everything flows from that."
The actor has previously admitted that his recent weight gain is an "issue", adding: "At my age, I have to watch everything I eat. I have to be really disciplined."
Crowe is in talks to star in the latest Superman movie, according to recent reports. However, Sean Penn and Clive Owen are apparently also both after the role as Superman's father Jor-El.
The Robin Hood actor was recently labelled "anti-Semitic" after calling circumcision "barbaric" on Twitter. He later apologised, saying: "I have a deep and abiding love for all people of all nationalities, I'm very sorry that I have said things on here that have caused distress."
Actor Eli Roth later jumped to Crowe's defence, saying: "I am deeply, deeply disturbed at the media's portrayal of Russell Crowe as an anti-Semite for making a joke to me on Twitter. [He is] one of the nicest people [I have] ever been lucky enough to meet and work with [and is] respectful of all religions".