Sulaiman Khan, 30, from London, took part in the charity's nine-month investigation and says there are "no-go zones" in London he cannot reach in his wheelchair.
Mr Khan, who has congenital muscular dystrophy, said disabled people are forced to make lengthy detours just to reach a destination.
He said: "I've constantly struggled to get to work opportunities and miss out on socialising."
The investigation was carried out by Muscular Dystrophy UK Trailblazers - a network of 700 young disabled people across the UK.
One researcher, Conrad Tokarczyk, said: "There is no step-free station on the Central Line from Ruislip until you get to Stratford. It has forced me to turn down jobs and generally made life more difficult than it should be."
The report investigated public transport access across the UK, including buses, trains and taxis.
Just seven fully accessible underground stations in zone one, out of a total of 67
Only 25% of stations provide step-free access across the whole Tube network
Common routes on the London Underground take more than four times as long for disabled people
Transport for London (TfL) said since 2008, step-free access has been introduced at a further 47 underground and overground stations, bringing the total to 117.
Forty more stations will become step-free in the next 10 years, TfL confirmed.
Gareth Powell, London Underground's director of strategy, said: "More than half of our underground and rail stations will be step-free by 2018 and the Elizabeth line, which includes 40 step-free stations, will open through central London at the same time - transforming access for disabled Londoners.
"In the meantime, we offer every assistance possible."