Answer: These restaurants often have a walk-up counter, but most customers will still dine in. As the name implies, the service is designed to be quick. However, it is one level above Quick Service (Fast Food). Basically, the service experience and walk-up counter experience of a McDonald's, but the food quality of a Chili's.
Abdominal muscles (more specifically transversus abdominis, internal and external oblique muscles) play a very important role in breathing for singing.
