Here is a photo I took last year at wedding. It was captured quite simply. The camera was a 5dMK2 set to ISO 3200 lens 28mm f1.8 set to f2.2 shutter speed was about 1/30sec. The important thing is the lighting 2x Canon 550ex set to wireless TTL and positioned either side of the Bride and Groom.
There was no way I could capture this shot using single shot mode on the camera. I needed to use the continuous shooting mode whereby the camera takes photos at 4 frames per second. This frame rate will vary by camera make and model and can be anywhere between 3 and 10 frames per second.
Each of the flashes had an external battery pack attached which reduced the recycle time and allowed the flashes to keep up with the camera.