Laboratory screening for rhabdomyolysis and reference laboratory values of muscular activity for beginners practicing vigorous exercises

الملخص EN

The objectives of this study were: screening for cases of exertional rhabdomyolysis among beginners in practicing vigorous exercises, and finding out reference laboratory values of muscular activity for the students who will exercise for the first time.

The study was conducted in Assuit university hospital on 222 male students of first year of faculty of sports, who practiced vigorous exercises for one hour with maximal load, for the first time, and 20 apparently healthy age matched males as a control group (GI).Twenty four hours after vigorous exercise (24hs AVE), blood samples were collected and the students were classified according to (CK) levels into two groups, group II (GII) :125 students, with total CK<183U/L(cut off value)and group III (GIII): 97 students, with total CK>183U/L.

One month after vigorous exercises (I m AVE), blood samples were collected from (GIII) which represent the follow up group (GIV, baseline).

All participants were subjected to medical history, clinical examination including body mass index (BMI), and quadriceps circumferences.

Laboratory investigations included peripheral haemogram, kidney and liver function tests, blood minerals, and specific tests including: total CK, CK-MB and CK-MM isoenzymes, LDH, and serum myoglobin.

This study revealed statistically highly significant elevation of total CK, CK-MM, CK-MB, AST, ALT and serum myoglobin when comparing (GIII) with each of (GI) and (GII) while a high significant reduction was found when comparing (GIV) with (GIII).

No significant difference for total CK and CK-MB could be detected when (GIV) compared with (GI).

There was a significant reduction in serum Na+ and serum Ca++ level and highly significant elevation in serum K+ and phosphorus in GIII when compared with GI.A significant elevation was detected in total WBCs, RBCs count , HB and Hct value in GII and III when compared with GI.

Twenty four hours after vigorous exercises, 16 students (7.2%) of the total participant students showed total CK level more than 5 times the cut off value (183 U/L).

Those students showed no signs and symptoms of rhabdomyolysis except muscle pain.

Conclusion: The participant students who showed total CK values five times or more than the cut off value (183 U/L), 24 h AVE are considered by some authors to be suspicious of having rhabdomyolysis.

Laboratory values of the students with total CK values < 183U/L, 24hs AVE could be taken as reference values for students and untrained persons who will practice exercise vigorously for the first time.

Most of the abnormal laboratory findings reported 24hs AVE, returned to normal values after one month, so the results should be interpreted with caution.