Final answer:
Isotonic tension is generated by external forces during muscle contractions that cause a change in muscle length, encompassing both concentric and eccentric contractions.
Step-by-step explanation:
Muscle and connective tissue generate tension when they contract against external forces. The type of tension generated by external forces that causes movement, or a change in the length of the muscle, is called isotonic tension. Within isotonic contractions, there are two subtypes: concentric and eccentric.
A concentric contraction involves the shortening of the muscle as it works to move a load, like lifting a weight upwards. On the other hand, an eccentric contraction occurs when the muscle elongates while still maintaining tension, such as slowly lowering a weight.
Isotonic contractions contrast with isometric contractions, where the muscle tension changes but the muscle length does not, such as when pushing against an immovable object. Understanding the distinctions between these types of muscular contractions is crucial for comprehending how muscles work to produce force and control movement under different physical demands.
The type of tension generated by external forces on muscle and connective tissue is eccentric tension. Eccentric contractions occur when the muscle lengthens under tension. An example of eccentric contraction is when a muscle is contracting against a load that is being lowered slowly and controlled, causing the muscle to lengthen.