But Michael said Essendon's training schedule differed from the Lions, which has since allowed him to end his brief retirement from the game and make a comeback to the AFL with Essendon.
"I got to round 15 last year and I was ready to retire then, because I was absolutely rooted basically, so that's pretty much where the decision to retire came from - it had nothing to do with playing football and I always wanted to play footy, but I just couldn't do both," Michael said after his first training session at Windy Hill on Monday.
"I'm glad I still get that chance to play, because deep down I still felt I had a lot to offer and at 29, it did seem a bit young."
And Michael confirmed he had never lost his desire to play at the highest level.
"To be honest, it never left. I always wanted to play football - I was just not prepared to do what I was doing and play football," Michael said.
"My health was suffering, so I'm just stoked that Essendon has given me the chance to play again.
"Last season, training everyday and doing my personal business commitments - I wasn't going to bed until 3am each morning and I wasn't prepared to do that again, but I'm glad Essendon has given me the chance to play again.
"I'm training with the group and I'll continue to train with the group and should I need to go away, I just have to inform the club and give them notice that I'll be taking off."
The triple Brisbane Lions premiership player said he may need up to two days off in a row throughout the season, in order to satisfy his business interests.
"Hopefully, I'll only be gone for 24 or 48 hours - maybe," Michael said.
"I'm trying to schedule that early in the week, so it won't clash with games on the weekend and I'll try and make myself available for all 22 games, plus finals."
Although Michael conceded he needed to catch-up on some training, he added he was now feeling refreshed and ready to tackle the 2007 season.
"In all honesty, I still probably need a couple of months to condition myself and I did the warm-up today and half an hour of skills and I was pretty tired after that," Michael said.
"For me, it was a good point to see where I was at and also it gives me an idea of where I need to get to for the start of the season.
"I actually feel pretty good because at the end of last season when I retired, I just had a mental break and usually when you go on holidays at the end of each season, subconsciously you keep thinking you have to be back at pre-season.
"For me, I went away to Thailand for a month and I went away and I felt really good and refreshed and it was the first time in 10 years that I've had that feeling, so coming back to training was pretty good."
