Harris hasn't donned silks since last October, having made the decision to take a respite from his constant battle with weight.
The 34-year-old has a far taller frame than his Hall of Fame father Noel Harris, who was able to make light weights throughout his long and illustrious jockey career, and for some years has struggled to ride below 57kg.
“It was time to give the old body a rest, I just couldn't keep doing it, but I'm feeling good again and I'm really looking forward to getting back into action,” Harris said.
“I've always done a fair bit of running – eight to 10 kilometres a day – plus I've taken up boxing again; it's really good for my fitness.”
Harris will make a cameo return to the ring on Friday night in one of six corporate grade bouts on NJE Promotions' card scheduled for the Sir Don Rowlands Centre at Karapiro.
“I'm not taking it too seriously; it's a bit of fun along with my training workouts.
“It's in the 60kg range and I'm planning to weigh in at around 59.5, so I won't have to lose much to make weight (58.5kg) for my ride on Sunday.
“In the past I've found myself having to lose sometimes three kilos on race morning and that's really tough, but hopefully I won't end up in that position any more.”
Harris has the full backing in his comeback of Te Akau trainer Mark Walker, with whom he served his apprenticeship from 2004 to 2009.
“It's going to be great having Troy back,” said Walker, “he's a genuine Group One rider and we need every one of them in the ranks.
“He's got a sixth sense; in a race he knows what's happening two or three pairs in front.
“We go back a long way and since I arrived back I've noticed how much more mature he is now, which I guess goes with being a father.”
Harris has a tally of 378 wins, 31 of them in black-type races and including a career-first Group One success on the Wayne and Vanessa Hillis-trained Dezigna in the 2008 Captain Cook Stakes.
Three weeks later he became one of those rare jockeys to get the last run at his father in a feature race, partnering the Walker-trained Tell A Tale to a head victory over Harris senior's mount Il Quello Veloce in the New Zealand 2000 Guineas.
Big wins Harris has enjoyed in more recent years include several on champion three-year-old Catalyst, headed by the 2019 Group 1 New Zealand 2000 Guineas (1600m).
Harris will continue to align himself with Te Akau, although that does not include any expectations of challenging Opie Bosson as the stable's first choice rider.
“Nah, Opie's got no worries there, I'd just like to think what he can't ride, I can; that will do me nicely.
“With a few other jockeys taking a break, right now is a good time to strike, get my eye back in and get my weight down gradually ahead of the new season.
“Asperitas is a nice ride that Mark has lined up for me to come back on.
“He only just missed at his last start and his work since has been good, so here's hoping.”