Furthermore, if the muscle length shortens, the contraction is concentric. But if the muscle length lengthens, then the contraction is eccentric. In natural movements that underlie locomotor activity, muscle contractions are multifaceted as they are able to produce changes in length and tension in a time-varying manner.uscle contractions can be described based on two variables: length and tension. A muscle contraction is described as isometric if the muscle tension changes but the muscle length remains the same. In contrast, a muscle contraction is isotonic if muscle length changes but the muscle tension remains the same.
Top definition. gut-wrenching. Adjective to describe something so painfully emotional, and tragic, that your stomach feels knotted. It relates to feelings of guilt, sadness and devastated sympathy. The really tragic suicide of ten year old Ashlynn Conner, from Illinois, suffering after being bullied, was described as 'gut-wrenching'. #devastated#heartbroken#shocked#horrified#disturbed#horrific#dreadful#gut wrenching#heart wrenching.
Definition of leech for Students. 1  1 : a bloodsucking worm related to the earthworm. 2  2 : a person who stays around other people and uses them for personal gain.