Background: Muscle soreness after exercise, called delayed-onset muscle soreness (DOMS), may cause significant changes in muscle function and may increase the risk of sports injuries. Therefore, various therapeutic strategies have been studied to help recovery after exercise. Jakyakgamcho-tang (JGT) is a widely prescribed herbal medicine to treat muscle pain and cramps in traditional Eastern medicine. The aim of this study is to evaluate the effect of JGT for reducing pain and improving muscle damage after exercise.Methods: This study is a randomized, double-blind, placebo-controlled, crossover design clinical trial. A total of 30 healthy male adults will be recruited. Subjects who voluntarily wish to participate in this study will be hospitalized for 4 days. On the first day, the subjects will perform a standardized treadmill exercise for 1 h to induce DOMS. After the exercise, the subjects will take either JGT or a placebo for 3 days. After a more than 1 week wash-out period, the subjects will repeat the same process with the other drug. Pain intensity, calf circumference, and pain threshold will be measured as outcome measures. Blood tests and blood pressure will be measured as safety assessments. In addition, blood tests for muscle damage and inflammation markers, such as creatine kinase, interleukin-6, and Creactive protein, will be analyzed.Discussion: This will be the first trial to assess the effect of JGT on exercise-induced muscle soreness. Our findings will provide valuable data to determine the clinical effects of JGT on DOMS.