“This is just the beginning, my vision is to keep growing, keep reaching more people, and keep pushing this movement forward”, he said.
Classes at the venue, on Bow Fell, start on 7 October will cost £7.50 per session.
Mr Brannen, who won the Midlands Elite title in boxing, got into teaching the sport after finishing college and signing up for a personal trainer course.
But after posting the video on Facebook of his brother, he received an influx of messages from parents and relatives of special needs children who wanted to hire him.
He said: “This is just the start of something powerful and I’m so grateful for everyone who has been part of it so far. The kit has started arriving for the new classes, and I couldn’t be more excited.
“Let’s keep proving that together, we can beat all odds.”