The name of the protein that helps in muscle contraction is actin. Actin is a globular protein that polymerizes to form long filamentous structures called microfilaments, which are essential for muscle contraction and movement. In muscle cells, actin filaments interact with another protein called myosin during the contraction process. This interaction is facilitated by energy produced from ATP, leading to muscle fiber shortening and generating force. Actin plays crucial roles not only in muscle cells but also in various cellular processes, including cell motility, division, and maintaining cell shape.