I am on the bike and I'm probably going to start jogging this week so everything is feeling very good.
"There's plenty of banter - I don't think they can wait to get me out of the treatment room because I seem to be wrecking the joint.
"But it's all about having fun and being happy in your environment. I am very happy and trying to keep the spirits up."
With the Third Ashes Test underway, Cahill admits that there has been plenty to talk about.
"We have had a few games of indoor cricket and the 10-yard bucket challenge in the treatment room, and I have got plenty more up my sleeve as well!
"The indoor cricket hasn't gone any better than the Ashes for the English lads. I think you are better then us at croquet though."
Cahill's high-spirits have been helped by the support of the physiotherapy team at Bellefield - led by Mick Rathbone.
Cahill said: "The biggest thing about the physios is the atmosphere and the way they make you feel.
"They are very good physios and it's a pleasure to come in and work with them one-to-one because being injured is a hard period for footballers but the treatment room is probably the heartbeat of the training ground because that's where everyone goes for the banter but the treatment is very thorough.
Boyo Do we need this lad back. Wonder if the early season Boo Bohyz have noticed how much we Suk without TC.........