Effect of White Willow Bark on Delayed Onset Muscle Soreness Following Resistance Training: A Pilot Study

[OBJECTIVES] Delayed onset muscle soreness (DOMS) is discomfort that occurs within 8-24hrs following an unaccustomed bout of physical activity that peaks within 24-27hrs and slowly resolves on its own. White willow bark (WWB) is a nutritional supplement that is believed to have anti-inflammatory and analgesic properties like aspirin but without the risk of GI adverse effects. The purpose of this investigation is to determine the effectiveness of WWB on alleviating the symptoms of DOMS following exercise. [METHODS] Twenty-five individuals volunteered to participate and were randomly assigned to take WWB (798mg salicin) or placebo for 5 days following a lower body resistance training session which consisted of 5X10 lunges at 40% body weight (BW) and 3X fatigue leg press at 75%BW. Test procedures included visual analog scale (VAS), mid-thigh circumference and pressure pain threshold. VAS was measured pre, all five days of the supplementation period and day 6 (post-supplementation). All other variables were measured at pre, immediate, day 3(72hrs), and day 6 (post-supplementation). [RESULTS] No condition X time interaction was observed (p > 0.05) for any variable. However, VAS scores were lower in the WWB compared to the placebo for all time frames. There was a significant main effect of time for VAS scores indicating muscle soreness for hamstrings (p < 0.001), gluteal (p < 0.001), gastrocnemius (p < 0.001) and quadriceps (p < 0.001). In addition, there was a significant main effect of time for right midthigh pressure pain threshold (p = 0.02), mid-right (p < 0.001) and mid-left (p < 0.001) thigh circumference. [CONCLUSIONS] WWB may reduce subjective feelings of muscle soreness and appears to have analgesic properties.