Here is another kit that could prove useful for your DIY wearable projects. The MyoWare Muscle Sensor Dev Kit is an Arduino-powered, electromyography (EMG) sensor kit that allows you to measure electrical activity of a muscle and gives you visual feedback through LED lights.
The kit has everything you need to set up the MyoWare Muscle Sensor. It comes with 3-pin headers to make stacking easier. You can get the kit here.