Final answer:
The statement is TRUE; during an eccentric muscle contraction, the muscle lengthens while still producing force. These contractions occur when, for instance, a weight is lowered slowly, and the muscle controls the movement.
Step-by-step explanation:
The statement An eccentric muscle contraction is when a muscle produces force while it is being lengthened is TRUE.
In the context of isotonic muscle contractions, where the muscle tension remains the same while the muscle length changes, there are two types: concentric and eccentric contractions. During a concentric contraction, the muscle shortens as it exerts force. An example of this is when you raise a hand weight and your biceps muscle contracts, shortening and pulling your forearm up. On the contrary, an eccentric contraction occurs when the muscle lengthens even though it is still under tension. This happens, for example, when you lower a hand weight slowly; the biceps brachii muscle increases in length as it controls the descent, despite the reduction in muscle tension. Eccentric contractions can help with movement control and balance.