<P> Microtrauma, which is tiny damage to the fibers, may play a significant role in muscle growth . When microtrauma occurs (from weight training or other strenuous activities), the body responds by overcompensating, replacing the damaged tissue and adding more, so that the risk of repeat damage is reduced . Damage to these fibers has been theorized as the possible cause for the symptoms of delayed onset muscle soreness (DOMS), and is why progressive overload is essential to continued improvement, as the body adapts and becomes more resistant to stress . However, work examining the time course of changes in muscle protein synthesis and their relationship to hypertrophy showed that damage was unrelated to hypertrophy . In fact, in that study the authors showed that it was not until the damage subsided that protein synthesis was directed to muscle growth . </P> <Table> <Tr> <Td> </Td> <Td> This article's factual accuracy is disputed . Relevant discussion may be found on the talk page . Please help to ensure that disputed statements are reliably sourced . (May 2017) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article's factual accuracy is disputed . Relevant discussion may be found on the talk page . Please help to ensure that disputed statements are reliably sourced . (May 2017) (Learn how and when to remove this template message) </Td> </Tr> <P> In the bodybuilding and fitness community and even in some academic books skeletal muscle hypertrophy is described as being in one of two types: Sarcoplasmic or myofibrillar . According to this hypothesis, during sarcoplasmic hypertrophy, the volume of sarcoplasmic fluid in the muscle cell increases with no accompanying increase in muscular strength, whereas during myofibrillar hypertrophy, actin and myosin contractile proteins increase in number and add to muscular strength as well as a small increase in the size of the muscle . Sarcoplasmic hypertrophy is greater in the muscles of bodybuilders because studies suggest sarcoplasmic hypertrophy shows a greater increase in muscle size while myofibrillar hypertrophy proves to increase overall muscular strength making it more dominant in Olympic weightlifters. These two forms of adaptations rarely occur completely independently of one another; one can experience a large increase in fluid with a slight increase in proteins, a large increase in proteins with a small increase in fluid, or a relatively balanced combination of the two . </P>

How long does it usually take for significant muscular hypertrophy from resistance training to occur