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First, the absolute tensions achieved can be very high relative to the muscle's maximum tetanic tension generating capacity (you can set down a much heavier object than you can lift [1]). Second, the absolute tension is relatively independent of lengthening velocity. Muscle injury and soreness are selectively associated with eccentric contraction.
Temperature gradients, thermal expansion or contraction and thermal shocks are things that can lead to thermal stress. This type of stress is highly dependent on the thermal expansion coefficient which varies from material to material. In general, the greater the temperature change, the higher the level of stress that can occur.
The amount of elongation and the load that will cause failure both depend on the force per cross-sectional area rather than the force alone, so stress = axial force / cross sectional area is more useful for engineering purposes than tension. Stress is a 3x3 matrix called a tensor, and the element of the stress tensor is tensile force per area ...
The stretch reflex operates as a feedback mechanism to control muscle length by causing muscle contraction. In contrast, the tendon reflex operates as a negative feedback mechanism to control muscle tension. Although the tendon reflex is less sensitive than the stretch reflex, it can override the stretch reflex when tension is great, for ...
Tetanic contraction can exist in a variety of states, including isotonic and isometric forms—for example, lifting a heavy box off the floor is isotonic, but holding it at the elevated position is isometric. Isotonic contractions place muscles in a constant tension but the muscle length changes, while isometric contractions hold a constant ...
Muscle contraction is the activation of tension-generating sites within muscle cells. [ 1 ] [ 2 ] In physiology , muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. [ 1 ]
Types of faulting. Anderson's theory of faulting, devised by Ernest Masson Anderson in 1905, is a way of classifying geological faults by use of principal stress. [1] [2] A fault is a fracture in the surface of the Earth that occurs when rocks break under extreme stress. [3]
Isolytic contraction is when a muscle contracts while external forces cause it to lengthen. [1] For example, during a controlled lowering of the weight in a biceps curl , the biceps are undergoing isolytic contraction.