Cyclists in Swansea who ride along the city's promenade at speeds of up to 30mph according to Strava are being urged to slow down.
Local resident John Roberts checked the ride-sharing site after becoming concerned at the speed some cyclists were riding at, reports the South Wales Evening Post.
Hehe discovered one rider had clocked more than 30mph crossing the Sail Bridge over the River Tawe, which is shared by pedestrian and cyclists.
Mr Roberts told the newspaper: "Our daughter is severely autistic and loves the outdoors and running, we tend to spend each dry day outside.
"We used to take her down to the sea front in Blackpill and Mumbles but we find speeding cyclists a safety hazard as they are fast, silent and seem to have disregard to pedestrians. We have to keep our daughter on reins but even then she has had a few near misses.
"We very rarely hear cyclists with bells and even so, if they did use their bell my autistic daughter wouldn't understand what the noise meant and I'm sure other young children wouldn't know what it means."
He asked: "Cars on the road where there are limited pedestrians have speed limits; why doesn't the same apply to cyclists on walkways?"
Cyclists using shared use facilities such as the Bristol & Bath Railway Path, which is maintained by Sustrans, to chase the fastest times on Strava segments have been a source of conflict with other users.
Sustrans' Cycling Code of Conduct for Shared Use Paths says riders should "cycle at a sensible speed" and "not use the paths for recording times with challenge apps or for fitness training."
Jane Lorimer, National Director at Sustrans Cymru, said: "In hot-spots where Sustrans has been made aware that cyclists are regularly travelling excessively fast in the past we have asked our local volunteers to help draw attention to the issues this causes other users.
"In these cases our volunteers have set up an information stand on the route, giving out copies of the Code and generally drawing attention to the need to share with care."
David Naylor, secretary of local cycle campaign group Wheelrights, said most cyclists and pedestrians using the routes concerned were courteous to each other, but added the speeds some riders had logged on Strava were "completely indefensible."
A spokesman for Swansea Council added: "All cyclists using shared paths need to use them responsibly and understand that these routes are also being used by pedestrians.
"It is not acceptable for cyclists to be travelling at high speeds and risk putting pedestrians and themselves at risk of injury if a collision occurs."