he phrase "two things can be true" is a frequent refrain in popular psychology and it's also a frequent response, I find, to witnessing the farther reaches of live art. Hmm, is this performance confusingly self-indulgent or utterly profound? Sometimes it can be both. In fact, it's not just two things that can be true, it's as many things as there are people in the audience, since this is all about the live subjective experience, in the moment; presence and connection.

Launched in 1998, Fierce is Britain's longest-running live art festival. For one week it takes over Birmingham's conventional theatres alongside unconventional spaces, especially in ex-industrial Digbeth, which is fast becoming a creative hub. Also on the bill this year: late-night artist dinners, a show in a swimming pool, and a six-hour performance jam at a grand gothic hall that was apparently the inspiration for Cluedo.

There's a focus on the sensuous and sensory; it's all about the physical body. But the first piece I experience is actually in virtual reality: Traversing the Mist, by Taiwanese artist Tung-Yen Chou. The setting is a gay sauna, and the VR tech is impressive. You walk through the grey concrete corridors, locker room, showers, cubicles, pushing aside curtains that you know aren't really there. You can open doors, pick things up, press buttons in the lift. You're an observer of the uncanny scene, which is peopled by identical blank-faced men; a sense of searching pervades, but there's zero joy or pleasure to be found.

The experience is a combination of immersive and detached. It's engaging, and yet eerily lonely – and also unnerving when the floor falls away, messing with your own proprioception. You feel, but what you feel is exactly the lack of connection. (Chou is also showing a short, sit-down VR piece called In the Mist, which was a precursor to the longer work, but is basically a sad porno.)

What you're missing in VR is the smells, the heat, the sweat. But don't worry, there's plenty of that elsewhere. Wojciech Grudziński's sweaty, hairy, all-too-human fleshy body is front and centre in his solo Threesome, his bum in the air as he does upside down pliés in a shoulder stand and other yogic moves wearing bottomless frilly knickers. In voiceover he tells us of three Polish ballet dancers who were shamed for their homosexuality, and Threesome is his attempt to reclaim their true identities, and make peace with his own "ghastly" body. Is a series of bum-bearing contortions followed by a ravey, repetitive jig the best way to do that? Well, it's Grudziński's way. And it's strangely compelling, building to a sort of catharsis, with lights and music and defiant mood.

Artist Melissandre Varin is known as n:u, and calls themself an "atmosphere-maker", which is interesting branding and perhaps modifies the expectations of the audience. Fierce is a thoroughly international festival, but n:u was previously based in Birmingham, although the work is rooted in Congolese, Guadeloupean, and Beninese heritage. I caught part of a rehearsal for the piece FREE(HOLD), an opaque ritual, in which performers drag ropes around their ankles and keen to the sky. Endurance, suffering, slavery and colonialism all rushed to mind.

This is a festival full of intriguing, conversation-starting stuff, but American choreographer Faye Driscoll blows everyone else out of the water with her acclaimed, award-winning piece Weathering, which gets its UK premiere here. Driscoll's work is a few levels up in terms of concept, commitment, execution and scale. It's essentially 10 performers on a rotating platform, a tableau vivant, or maybe less a living tableau than one that's slowly distorting and decaying and caving under the gravity of life's pressures, or just the passage of time.