Effects of Delayed-Onset Muscle Pain on Respiratory Muscle Function.

Background: Delayed-onset muscle soreness (DOMS) has been widely examined in the peripheral muscles; however, studies showing the potential effects of DOMS on respiratory function are limited.

Hypothesis: DOMS in trunk muscles has a negative effect on respiratory function parameters, respiratory muscle strength, respiratory muscle endurance, and exercise capacity.

Study design: Prospective cohort study.

Level of evidence: Level 2.

Methods: In 24 healthy participants with a mean age of 21 ± 2 years, DOMS was induced for the trunk muscles with a load equal to 80% of the maximum repetitive voluntary contraction. Pulmonary function parameters, respiratory muscle strength and endurance, exercise capacity, pain, fatigue, and dyspnea perception severity were recorded before DOMS and at 24 and 48 hours after DOMS.

Results: After DOMS, decreases were observed in respiratory function parameters, namely, forced vital capacity, forced expiratory volume in the first second, vital capacity, and 25% to 75% flow rate value of forced expiratory volume (25% to 75%) (P = 0.02, P = 0.02, P < 0.01, P = 0.01, respectively). Maximal inspiratory pressure and exercise capacity also decreased (P = 0.02, P < 0.01, respectively). No difference was observed between all 3 measurements of maximal expiratory pressure (MEP) and MEP% values (P₁ = P₂ = P₃ ≥ 0.99). The results of the respiratory muscle endurance tests did not reveal a significant difference in terms of load and time in all 3 conditions (P > 0.05).

Conclusion: After DOMS, there was a 4% to 7.5% decrease in respiratory function parameters, and a 6.6% decrease in respiratory muscle strength.

Clinical relevance: The occurrence of DOMS before a competition can have a detrimental impact on pulmonary performance. Hence, it is imperative to consider this factor when devising training and exercise programs. In addition, the development of treatment protocols becomes crucial if DOMS arises.