Diagnostics of delayed onset muscle soreness

Aim. The paper investigates the diagnostic capabilities of a complex of clinical, laboratory, and functional parameters for delayed onset muscle soreness (DOMS) in people involved in physical education and sports. Materials and methods. The study included 25 people aged 21 to 41 years (13 women and 12 men), mean age 32±2.5 years, who engaged in regular physical activity. The study participants performed DOMS-inducing physical activity with an emphasis on the eccentric phase of movement and with maximum amplitude. The target muscle group was the quadriceps femoris. Data from clinical and biochemical blood analysis, force platform measurements, heart rate variability at rest and during exercise, bioimpedance analysis of body composition, pupillometry, exercise ergospirometry, myography, back dynamometry, and the results of a questionnaire based on a visual analogue scale of pain were obtained the day before and the day after the DOMS-inducing exercise. Results. In response to the DOMS-inducing physical exercise, the following observations were made: 1) pain in the target muscle group, 2) decreased blood count values (red and white cells), 3) increased levels of CK, 4) reduced pupillary constriction speed in response to light stimuli, 5) upward trend in electromyographic activity, 6) changes in the displacement of the center of pressure in the frontal and sagittal planes. Conclusion. The following diagnostic signs can indicate the development of delayed onset muscle soreness, which was verified by a significant increase in exercise-associated muscle soreness: increased levels of CK, reduced pupillary constriction speed in response to light stimuli, fatigue of the postural muscles. A DOMS diagnosis can be included in the measures of medical and biological support of athletes to prevent a decrease in sports performance.