Dame Sarah Storey, 41, announced she will lead the active travel agenda in the Sheffield City Region at an event at Sheffield Hallam University.
The cyclist and swimmer is the most successful female British Paralympian of all time, with 14 gold medals, and has broken 76 world records during her career.
Her role will involve championing active travel and working alongside Mayor Jarvis to create a region in which more people travel on foot, by bike or by public transport.
Dame Sarah is also keen to create more links between Barnsley and the surrounding towns, by creating an infrastructure whereby people can walk and cycle to areas such as Doncaster and Sheffield.
She said: “I am keen to help create infrastructure that will allow people to travel across the region by cycling or walking.
“Barnsley has the Trans Pennine trail, which is fantastic, but it would be great to have more that is accessible for all.
“I will be speaking to the people of Barnsley and asking what they want to see. Active travel is more than just encouraging people to be active, it’s about being healthy and improving air quality.
“I’m not a transport expert but I believe I have the ability to influence and make changes to the way people travel and allow people to enjoy being active.”
Dame Sarah will work with organisations such as local authorities, the Passenger Transport Executive, community groups and public health professionals, as well as with national government.
“I want people to have a better and viable alternative when it comes to travelling. It will be more than just painting a white line on a road and calling it a cycle path. I want infrastructure that works and one that will last for years to come for all to enjoy, whether you are cycling, in a scooter, a four-wheel bike or walking,” she added.
“We have backing from the Transforming City Funds and we will look to secure more funding wherever we can as the ball starts to roll and things begin to take shape.
“I am excited to work alongside the people of Barnsley and make this a success.”
Mayor Dan Jarvis said: “I’m delighted to name Sarah as our active travel commissioner. To have such an exceptional, inspirational and passionate individual leading our active travel agenda is very exciting.
“Sarah joins us at an exciting time and will play a crucial role in helping us to make sure that active travel remains an absolute priority as we make our region’s transport network fit for the 21st century.
“By prioritising active travel, we can improve people’s health, cut carbon emissions and reduce congestion. But you don’t have to be a professional cyclist - or indeed a gold medal winning cyclist - to travel in a more active way. By making little changes to the way that we travel, we can all do our part to create a healthier and more active society.”