The cycle continues as the mass vibrates back and forth about a fixed position. The springs inside of a bed mattress, the suspension systems of some cars, and bathroom scales all operated as a mass on a spring system. In all the vibrating systems just mentioned, damping is clearly evident.
[Continued from above] . . . Contraction of the quadriceps group extends the leg at the knee and flexes the thigh at the hip. The hamstring muscle group extends across the posterior surface of the thigh from the ischium of the pelvis to the tibia of the lower leg.
Most muscles are also responsible for more than one type of movement. Movements of the hip are described in anatomical terminology using anatomical terms of motion. The movement that brings the thighs close to the abdomen is called flexion.ost muscles are also responsible for more than one type of movement. Movements of the hip are described in anatomical terminology using anatomical terms of motion. The movement that brings the thighs close to the abdomen is called flexion.