When Gail Collins stepped out in front of the deafening 80,000-strong crowd watching the Olympics opening ceremony, wearing a high-neck Edwardian blouse and the purple, white and green sash that marked her out as one of Danny Boyle's 50 suffragettes, she couldn't hear the noise, just the beating of her heart. "It was one of the biggest days of my life," she said. "Getting married, having my children and being in the opening ceremony. I felt proud, really proud that we had got there."

In the months before the ceremony, the women forged a particular bond – with each other and the women they were representing. So when the experience ended, what did the Olympic suffragettes do? They kept marching.

Dozens of suffragette performers, led by Helen Pankhurst, great-granddaughter of Emmeline Pankhurst, plan to march on parliament, at the vanguard of a major feminist rally organised to urge MPs to stop "eroding erosion of women's rights" and make more progress on women's equality.

Some of the suffragettes had no experience of campaigning and some younger cast members knew little about the women they were representing, but many now want to use the experience as a springboard into modern-day activism, starting with UK Feminista's rally on 24 October. "Coming together was a gift and it would be such a wicked waste to not carry on and we can't let people down by not continuing," said 37-year-old Collins, a stay-at-home mother of two.

No longer under the guidance of Boyle – who included the suffragette section in the ceremony after becoming enthralled by the memorial plaque to Emily Davison, found on the back of the broom cupboard door where she once hid in the House of Commons – the group may treat observers to a scaled-down version of their performance. It may even include the critical moment, which to the annoyance of many wasn't featured in the TV coverage, when the women formed a human scaffolding to carry a Christ-like Davison above their heads.

Another suffragette, Lesley Covington, a 57-year-old who gave up her job as a designer 20 years ago to look after her children, had never thought of herself as a feminist activist. "I'm not sure I would even now," she said. "But why shouldn't we take this opportunity? Women are still under-represented in parliament and the upper echelons of business; childcare is a huge issue. I want to get involved and I want to make a difference. You can change things – you have to believe that, or you would never try."

The opening ceremony and the Olympics as a whole, which involved women from every nation participating for the first time, as well as huge success for female athletes, could inspire many more women to campaign for gender equality, said Pankhurst, an ambassador for the global anti-poverty charity Care International.

"When we see things like women's boxing it is important, because it starts to shift perception about what women should and shouldn't do. The Olympics is a real platform to make it more than just symbols and this rally is really building on that."

While Pankhurst said political struggle was "in her veins", other women in the group had become "interested in the issues as well as the fun", after keeping in touch via Facebook. "Modern technology is allowing us to organise as suffragettes much easier than they did in the past – it unlocks the potential," she said. "Until we are on an equal footing and [while] unnecessary problems remain there will continue to be a need to speak out."

The suffragettes – who hope to track down Edwardian costumes for the rally – will join a broad coalition of groups that includes the TUC deputy general secretary, Frances O'Grady, and the director of Liberty, Shami Chakrabarti, and organisations including the Fawcett Society, Southall Black Sisters and the anti-objectification group Object.

Many protesters are requesting meetings with their MPs, while others will remain outside parliament to highlight issues such as a lack of progress on tackling violence against women, and making more women visible in parliament and in business. Other demands include measures to tackle the objectification of women – also put to Lord Justice Leveson during his inquiry into the ethics of the media – childcare and the protection of Sure Start centres, justice for female asylum-seekers and the protection of women's reproductive rights.

"The time is right for this. There is anger, injustice and potential, and that all comes together in 2012," said Chakrabarti.

Britain is witnessing a resurgence of feminist activism as hard-won rights come under threat, said Kat Banyard, the founder of UK Feminista.

"Too often, issues relating to women's inequality are put to one side and seen as an add-on, but tackling this injustice is absolutely central to building a good society.

"People are sick of the attacks on women's rights and are fighting back. At the lobby, women and men from across the country will be making it clear to their MP that we can't go on like this, it's time to move forward."

For Collins, taking part in the opening ceremony has given her a voice, and she is determined to use it.

"It's not fashionable to say you are a feminist, but women need to stand up," she said. "I've always had these beliefs but this has pushed me to do something about it. It just feels like I'm not on my own."