Children can practice the muscle relaxation techniques by tensing and relaxing different muscle groups. Myosin phosphatase is an enzyme that plays a role in muscle tensing (contraction) and relaxation. This causes contraction (tensing) of the muscle. Tics can be invisible to the observer, such as abdominal tensing or toe crunching. The tensing is detected when the abdominal wall is pressed. In each session the teacher reviews tensing one particular muscle group. The intermandubularis works by tensing the mouth floor. The body camera recording of Tensing shooting DuBose has garnered considerable attention. Tensing fired after DuBose started his car. Five years later, Sam DuBose was shot and killed by University Police Officer Raymond Tensing. The prosecution then announced they did not plan to try Tensing a third time. The charges against Tensing were later dismissed with prejudice.