Bowe missed the first game of the three match test series against Australia having suffering a broken hand earlier in the tour and replaces Alex Cuthbert on the right wing.
The Ireland international went through a strenuous regime in order to regain his fitness, and he admits that being picked to start against the Wallabies has warranted his efforts.
"It has been a real rollercoaster few weeks and I've done everything and anything to try to get it fixed. I've been taking protein shakes, calcium tablets, omega tablets and vitamins as well as having constant icing and physio two, three or four times a day," Bowe told Sportsmole.co.uk.
"To go from seeing the fracture put up on the board, the X-Ray, to be shown the fracture spiral right through the bone and be told that that's pretty much my tour over to being told by the surgeon that he's had guys come back within three weeks was emotional. But that enabled me to get back for selection for the second Test. Then I had to go through all the physio and everything else to try and get myself back and available - it has been a bit of a rollercoaster.
"But these are the sort of games that you want to be involved in. You play your career in rugby to play in big games. Getting injured is the hardest part of professional sport. Whenever you get picked to play in a match like this it makes it all worth it - as long as you win. That's the big thing and that's the motivation for us this weekend. The boys did all the hard work last weekend, it's the second half now and we need to come out with a good performance."
In the only other change in the backline, scrumhalf Ben Youngs replaces Mike Phillips.
Gatland has made three changes to his starting pack with loose forward Dan Lydiate replacing Tom Croft, while lock Geoff Parling has come in for the injured Paul O'Connell. Mako Vunipola starts at loosehead prop after Alex Corbisiero was ruled out with a calf injury.
Prop Ryan Grant, a late call-up for the tour, has come onto the bench as one of the front row replacements, while flanker Sean O'Brien and scrumhalf Conor Murray have been brought into the matchday 23.
The Lions beat the Wallabies by 23 points to 21 in the first test and are aiming for their first series win since 1997.
BRITISH & IRISH LIONS:
15: Leigh Halfpenny (Cardiff Blues/Wales)
14: Tommy Bowe (Ulster/Ireland)
13: Brian O'Driscoll (Leinster/Ireland)
12: Jonathan Davies (Scarlets/Wales)
11: George North (Scarlets/Wales)
10: Jonathan Sexton (Leinster/Ireland)
9: Ben Youngs (Leicester Tigers/England)
1: Makovina Vunipola (Saracens/England)
2: Tom Youngs (Leicester Tigers/England)
3: Adam Jones (Ospreys/Wales)
4: Alun Wyn Jones (Ospreys/Wales)
5: Geoff Parling (Leicester Tigers/England)
6: Dan Lydiate (Dragons/Wales)
7: Sam Warburton (Cardiff Blues/Wales) CAPTAIN
8: Jamie Heaslip (Leinster/Ireland)
REPLACEMENTS:
16: Richard Hibbard (Ospreys/Wales)
17: Ryan Grant (Glasgow Warriors/Scotland)
18: Dan Cole (Leicester Tigers/England)
19: Tom Croft (Leicester Tigers/England)
20: Sean O'Brien (Leinster/Ireland)
21: Conor Murray (Munster/Ireland)
22: Owen Farrell (Saracens/England)
23: Alex Cuthbert (Cardiff Blues/Wales)