Abstract
We studied the nature of biphasic changes in serum creatine kinase (CK) activity with transient weight training.
Six untrained healthy men (21-24 yr) participated in the programme. Six different types of weight training (70-80% maximum muscular strength) were imposed. Blood specimens were collected on nine separate occasions and CK activity, calcium (Ca), inorganic phosphate (Pi), zinc (Zn) and polyamine concentration were measured.
Muscle soreness was also examined by asking the men to fill out a questionnaire.
Muscle soreness appeared one hour after training and was considerable one and two days after the training.
CK activity showed a typical biphasic change. The extreme mean values (highest or lowest) of Ca, Pi, Zn and polyamines appeared between two and three days after the training. This period of time corresponded to that between the first and second peaks of CK activity. The first peak of CK activity after weight training was assumed to be related to muscle soreness. We propose that changes in blood Ca, Pi, Zn, polyamines and muscle soreness reflect a series of different histopathological reactions including muscle damage, repair and regeneration in subjects given transient weight training. Each peak of the biphasic change in serum CK activity may be different in nature, histologically and/or biochemically.
