The coaches at Sleaford Town Juniors, who make free sanitary products available to female players, said the importance of sports bras had “become more of an issue”.
John Williams, who co-ordinates the girls’ teams, said they had educated players about how an ill-fitting sports bra can create an imbalance when running and cause injury.
“It doesn’t just impact their sport but it can impact them later in life too,” he said.
The players at the club have backed the campaign for free sports bras saying it would encourage others to get involved.
In October, Miss Halsall won a competition run by Politika, a youth-orientated think tank, which asked young people to identify an issue which impacts their lives.
Chief executive Ben Rich said: “Rosie won because her submission was based on her own experiences.
“Because of what she had been through, she identified a real problem. That’s what we liked.”
The group has already been contacted by a company which offers sports bra fittings at schools which want to work with Miss Halsall on her proposal.
