It IS a full-on Glory day in Govan - that is to say rehearsals are hitting a close-to-first-night stride in the Pearce Institute there.

Busy hands are locking together the angled wooden frames that will translate Richard Layzell's designs into a 3D echo of the Commonwealth Athletes Village. On the far-end platform, overlooked by silent organ pipes, composer Michael John McCarthy is pressing laptop buttons and sending spirals of sound swooshing round the space. In the middle of the floor - clad in unfussy black - is the slight, lithe figure of choreographer/co-director Janice Parker. And she is saying: "Turn up the volume, turn up the volume!"

She is not talking to McCarthy, however. She is encouraging the dancers that surround her to let themselves flood, without inhibition, into the movement. Feel the glory, the joy - and for some of them the unexpected surprise - of their own creative physicality. And indeed, as the patternings begin to take shape or connections blossom between partners from different cultures, different ages, different abilities (equality of integration is intrinsic to this mix), the effect is simply glorious.

The morning session ends. The 16 performers head off. Parker takes a break and waits for the second group to arrive, when the whole process will start all over again. "All kinds of reasons meant working with separate sections," she says. "So I won't have everybody in the one room at the same time until the week before we open at Tramway."

For some people this would be unthinkable. But Parker is laughing as she sketches out how this ambitious jigsaw is going to piece together. "It's been really exciting," she says. "It means people will have to be totally aware, in the moment every moment, when they come to perform. It will still feel fresh to them, and that energy will reach out to audiences. They will see it, and feel it, and share in it - because they are very much a part of Glory too."

So much so that when audiences turn up at Tramway they will be treated to live-feed footage of the performers' warm-up, a bit of what Parker calls "foyer kerfuffle", a chance to experience the installation design on stage, plus a sneaky look into the dressing rooms and backstage areas.

This kind of spy-cam introduction to Glory is, like co-director Richard Layzell's set design, connected into the sporting side of Glasgow 2014, a choreographed parallel to the preparations we have come to understand are an essential part of competitive athletics. But the 2014 Games are being held under the banner of the Commonwealth: how does that construct sit in terms of Glory?

Parker has an instinctive habit of briefly pausing, ordering her thoughts, before she answers questions that have stirred complex responses in her own mindset. In the run-up to making Glory, she had considered the past and present history of the Commonwealth nations; registered the conflicts and harsh, hard times within those histories. But then she freed up that background, or rather dissolved it into ideas of borders and boundaries and the journeys people made and still make.

"I was asking myself, 'What does it mean, to all be under one roof, as it were? And what connects us?' And then that word 'connections' really took hold. Everyone involved has written down something about what Commonwealth, connections and being a part of this particular journey means to them. All of that has come into the room with them. I see that as something very rich, very positive - our common wealth, if you like."

There were no auditions, as such. An open invitation to take part has brought in a brilliantly random array of individuals, some with learning difficulties, some with previous dance experience, and some with only their curiosity and a willingness to try as a foundation.

Father and daughter Paul and Kirsty Nicolson are a fine example of both sides of that coin. Kirsty has the track record - she has worked with Parker on previous projects, including Private Dancer (which won a Herald Angel award in 2010) and the more recent Private Party. Paul, having seen both productions, had a hankering to join in - the fact that they were "short of men, and men of my age" was a clincher. So now he is driving to and from Peebles, where he has a photographic business, and discovering that the real journey is the one he is making in rehearsals.

"You keep finding that something is pulled out of you that you did not even know was there," he says. "And afterwards, it doesn't leave you. You have crossed some kind of personal boundary." In 1926, his great grandfather did not just cross oceans to reach Canada, he walked 1400 miles from Winnipeg to Vancouver, pulling his infant son on a sledge. It is as if, for Paul, the whole Glory experience has forged new connections with that aspiration and determination.

Kirsty, meanwhile, makes no bones about how she feels about the processes and values that underpin Glory. Now a professional physical theatre performer, and also working with Garvald Edinburgh, she says "becoming a part of what Janice does has transformed my life. I was not confident about moving my body. I had come along as a support worker to an earlier project and Janice just said, 'Why don't you join in?' I had no practice clothes, but I had my pyjamas in my bag - and I just put them on and - well, I have never looked back since.

"I trained professionally, I now work in physical theatre in the community. I still remember how powerful it felt, and how powerful it still is, when people - with or without learning difficulties - realise they can be creative, can express themselves in dance."

There is a pause, and a chuckle. "I mean, we have all seen an incredible difference in my dad!"

Glory is at Glasgow's Tramway from March 5-10, part of the Glasgow 2014 Cultural Programme. For details, see: www.tramway.org