Off the back of a tepid display from City in midweek against Walsall, Parkinson got just the response he was looking for from his side as the Bantams picked up an eye-catching victory thanks to a determined and disciplined team performance.
The morale-boosting win, sealed by Aaron Mclean's second City goal this season, helps to push Parkinson's men back into the top half of the League 1 table and further away from the relegation zone.
Parkinson said: "I thought we were terrific today (Saturday).
"It was tough on Tuesday because we played poorly. There were some reasons for that - Andy Gray playing with shingles and (James) Hanson not starting certainly didn't help - but we know there wasn't enough fight and determination in the side.
"We certainly got that back today, and we got our rewards.
"Leyton Orient are a good side - they have scored a lot of goals this season - but we looked at their game against Oldham Athletic on Tuesday and felt that Oldham had a lot of chances against them on the break.
"That is why we set up the way we did today with (Adam) Reachy and Benno (Kyle Bennett) wide and Jon Stead and Aaron (Mclean) up top.
"We felt that if we were solid in our defending, we would get chances on the break.
"We had to manage some pressure at times, but the back four and Jonny (McLaughlin) were immense and we seemed to grow in confidence once we got the goal. We probably had the best chances in the second half.
"It is a massive win for us. We had those two good performances against Colchester and Gillingham recently but we went away from things slightly after that. Whether the lads took a breather in terms of their performances I don't know, but it certainly looked like that.
"We had to get our performance levels back up there and today we did. We had five loan players in the side but the commitment they showed throughout the game was tremendous. They were great today, every single one of them.
"The fans know that over the last couple of years we have been all about the intensity of our play but that is sometimes hard to keep up when you have a lot of loan players in the side. I have to give them all credit, however, because today they put in a great performance."
With James Hanson left in Bradford to give the striker an opportunity to try and get over his back problem, recent loan signing Jon Stead was given his City debut at Leyton Orient.
Parkinson added: "I thought Jon did excellent for us today.
"He is a different player to James Hanson. He is obviously a target man but he has different qualities to James. He put an honest challenge in when the opportunity was there and he made some great runs to stretch the pitch for us.
"But most of all he added some more character to the team, which is something we needed after Tuesday."
One of the many plus points to come from the Bantams' victory at the Matchroom Stadium was the hard-fought shut-out against Orient's potent attack.
City's defensive efforts in the game weren't helped, however, by left back Adam Drury's withdrawal midway through the first half due to a knee injury.
Parkinson explained: "He has damaged his medial ligament. We're not quite sure at the moment how long it will keep him out for.
"Adam has been great as a lad and it will be a blow to have him out for any period. Carlo (McHugh) came in today and did a good job for us though.
"We all hope we can get Adam out there sooner rather than later."
Parkinson was forced to watch the second half from the Directors' Box at the Matchroom Stadium after being sent to the stands at half-time following an altercation with Leyton Orient assistant Kevin Nugent.
The half-time issue begin after Orient felt aggrieved not to get a spot-kick when Dean Cox's shot appeared to strike Andrew Davies' arm inside the box, despite the whistle having already sounded for the break a couple of seconds earlier.
Parkinson explained: "I think the frustration from their bench was that the ball did seem to hit Andrew (Davies) on the arm but the whistle had already gone for half-time so they didn't get a penalty.
"Kevin Nugent then had a go at me for appealing for decisions for our team. Sometimes when you're away from home you don't get the tight decisions go your way and I didn't think we were getting the rub of the green.
"I've said some words back to him and there was a slight altercation. I don't really want to say too much, however, and get Kevin Nugent in trouble.
"The referee has decided to send me off thereafter and I will be speaking with him after the match to find out what I did to deserve getting sent off.
"Most importantly though, I don't want anything to detract away from our performance because I felt we were excellent."