I had a PLIF surgery at L4/L5 (2013), so a similar process.
I was walking the day after the surgery. Walking was the bulk of my exercise for the first 2 months, then I started to get back on my bike (indoor trainer) at about 2-3 months.
I was fully recovered by about 7 months and racing my bike again.
Because of the fusion, I lost a little flexibility in my lower back, but not much to make a difference. I run, ride, XC ski with no noticeable issues. In the gym, I don't do heavy dead lifts as the initial lifting motion puts some stress on my lower back, but I can do as much weight as I like on the leg sled.
Went into surgery at 8:30 am. Was on my feet by 6pm. Spent three days in the hospital, mainly to monitor my gastrointestinal system‘s return to normal and to ensure I could do stairs (which they had me doing by day 2).
Great thing about ALIF is that no muscle is cut to access the spine. Plus, they don’t have to work around the spinal column. That makes overall recovery time much quicker. I was back at work (desk job) in less than a month, when I was cleared to drive.
Bad things were that in order to access the spine they have to move your guts out of the way. This involves pulling some of the intestines out of the body during surgery. Your body’s natural response to that is to shut the system down. Takes a bit to get that restrated. Nothing but clear fluids for days, and then a gradual work up to solids. For a meat eater like me, that was pretty much torture. Also, because of the fluid diet, your BMs are pretty messy and you will not be able to clean your backside by yourself for about a week. That is when I learned that my wife truly loved me.
Overall, I was back at full capacity in less than 6 months. Was able to drop a lot of weight because I could actually get around without constant pain. I still limit how much I lift and carry because I don’t want to put too much stress on my L3/L4. 50 lbs is my limit.
Overall, I am super glad I did it when I did and I am glad I did ALIF instead of PLIF.