effects of a single bout of eccentric resistance exercise on urea, creatinine and 3-methyl histidine excretion in normal college males.

introduction: strength training has an important role in the exercise programs of normal individuals and athletes and it also has numerous benefits on the health of human body and spirit. one of the types of these exercise is eccentric resistance exercise which is associated with negative physiological changes. thus: this study examined the effects of a single bout of eccentric resistance exercise on the urinary markers of protein catabolism and muscle damage such as urea, creatinine and3-methylhistidine (3mh).material and methods: for this purpose, 24 healthy non-athletes male student volunteers (age; 20±1.54, body mass index 22.6±3.8 and body fat percent 13.41±4.21) selected and were divided randomly into two groups experimental (n=12) and control (n=12) group. after determining the maximum power of the non-dominant hand, experimental group performed a single bout of eccentric resistance exercise including 50 eccentric contractions as five sets of 10 eccentric contractions with a one minute rest interval between sets, at ٪85 of 1-rm with non- dominant hand. urinary of samples to assess urea, creatinine and 3-methylhistidine were taken before exercise until 14 hour after intervention. data were analyzed using independent sample t-test at p results: results showed significant increase in urinary urea, creatinine and 3-methylhistidine after an eccentric resistance exercise in experimental group compared to control group. discussion: it is concluded that a single bout of eccentric resistance exercise results in an activation of the muscular protein catabolism, and muscle damage due to increase in degradation of myofibrillar contractile protein.