Specific force "Contractile force analysis or tension, which is expressed in Newtons (N) is not a very informative parameter for engineered muscles, because it does not relate to the size and condition of the tissue construct. Instead, the Specific Force (sF), also referred to as mechanical stress, is the CF normalized to the cross-sectional area (CSA) of the construct, and it is expressed in Pascals (Pa = N/m2)" https://doi.org/10.7554/eLife.77204