Methods of increasing the perceived thickness and strength of a thermoplastic film include incrementally stretching thermoplastic films in the machine direction. In one or more implementations, methods of incrementally stretching thermoplastic films include reducing the gauge of the films while increasing a loft of at least a portion of the film. The methods can involve cold stretching the films and imparting rib patterns and alternating peaks and valleys into the film. The linear ribs can have alternating thick and thin gauges.