Final answer:
An increase in connective tissue within muscle tissue from inactivity or aging typically leads to decreased power generation, reduced ability to produce high forces for actions like jumping, and increased muscle stiffness, all of which are effects associated with sarcopenia.
Step-by-step explanation:
An increase in connective tissue within muscle tissue due to inactivity or aging is likely to bring about several changes. The condition known as sarcopenia is characterized by an irreversible atrophy of muscles.
Decreased ability to generate power: As muscle fibers are lost and replaced by connective tissue and adipose tissue, the muscles' ability to produce powerful contractions is reduced. This occurs because connective tissues cannot contract and generate force as muscle can, resulting in a decline in muscle mass and a loss of strength required for various activities including sports that require strength and powerful movements like sprinting.
Decreased ability to generate high forces with jumping: The reduction in fast glycolytic (FG) fibers that quickly hydrolyze ATP for short, powerful contractions means that muscles become less capable of generating high forces required for explosive actions such as jumping.
Stiffness: The reduction in muscle mass and increase in connective tissue can lead to greater stiffness in muscles. Also, with increased age, collagen in connective tissue decreases, contributing to joint stiffness and reduced flexibility.