High CK levels are common in bodybuilders and athletes for two reasons: 1) we use creatine and 2) we train hard. Both are known to increase CK. The best thing to do is to take a week off training and creatine before your next liver enzyme test and you may find that your CK returns to normal. If not take a month of creatine (to bring levels back to baseline) and a week off training before the next test. If CK is still high, then you may have a legitimate liver problem, which you need to discuss with your doctor (as I'm not qualified to diagnose disease).