The idea of folding fabric to complete a circuit got me thinking about when I frequently see that movement in my normal life. The idea that seemed to stick with me is the idea of a garment that tells you when your form is correct, like a built-in spotter. The design I settled on was an armband specifically for bicep curls. When the arm is fully flexed and the weight lifted high enough, two pieces of conductive fabric touch and light up an LED, indicating that the repetition was successfully completed.
An extension of this idea would be to connect the circuit to a fitness tracker, so an app can automatically track completed reps and ignore failed or incomplete ones.