To be honest, I have yet to find a quality mass gainer on the market. The problem with most mass gainers is that they are loaded with cheap sugars as a carb source. Not only can this lead to greater fat gain, it can make drinking them several times a day unhealthy.
Mechanical stress: physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion.
There are two types of stress that a structure can experience: 1. Normal Stress and 2. Shear Stress. When a force acts perpendicular (or normal) to the surface of an object, it exerts a normal stress. When a force acts parallel to the surface of an object, it exerts a shear stress. Let's consider a light fixture hanging from the ceiling by a rope. The cross section of the rope is circular, and the weight of the light is pulling downward, perpendicular to the rope. This force exerts a normal stress within the rope.