Creatine and Muscle Soreness?
It’s long been a myth that if you didn't get sore from your last workout, then you didn’t work hard enough and you probably didn't improve. But it's just a myth. Soreness is not an indicator of a successful workout.
Muscle soreness that occurs directly after a workout is known as acute muscle soreness. Muscle soreness that appears 12 to 48 hours after exercise is known as delayed onset muscle soreness (DOMS) or post exercise muscle soreness (PEMS).
Acute muscle soreness or inflammation can last up to an hour after exercise and can be caused by a reduction in normal blood flow to the muscle and a build up of metabolic byproducts like hydrogen ions or lactic acid.
The physiological mechanisms that cause DOMS or PEMS are not completely understood but the leading hypotheses are: (1) the Connective Tissue Damage Hypothesis, (2) Skeletal Muscle Damage Hypothesis, and (3) The Spasm Hypothesis.
Connective Tissue Damage Hypothesis.
In a 1997 study, Brown, Child, Day and Donnelly reaffirmed an early study done by Abraham suggesting that DOMS or PEMS is due to a disruption in the connective tissue of the muscle and tendinous attachments.
Skeletal Muscle Damage Hypothesis.
In a 1986 study, Clarkson et al found that serum creatine kinase concentration was elevated with concentric, eccentric and isometric contractions, with greater perceived muscle soreness associated with the eccentric contraction. In a 2000 article entitled “Effects of Plyometric Exercise on Muscle Soreness and Plasma Creatine Kinase Levels and its Comparison with Eccentric and Concentric Exercise” (The Journal of Strength and Conditioning Research: Vol. 14, No. 1, pp. 68–74), the authors found Clarkson’s study not only proved to be true but also concluded that plyometric activities had incurred perceived muscle soreness than concentric contractions.