Novel Form of Curcumin Attenuates Performance Decrements Following Muscle Damaging Exercise

Abstract

It is known that unaccustomed exercise especially that with an eccentric component causes muscle damage and subsequent performance decrements. Attenuating muscle damage may improve performance and allow for greater performance adaptations. Curcumin, a highly pleiotropic molecule, interacts with multiple inflammatory pathways, primarily by inhibiting the IκB Kinase (IKK) signaling complex thereby preventing the activation of nuclear factor‐kappa B (NF‐κB). Curcumin has been reported to blunt the inflammatory response and attenuate performance decrements typically observed following exercise induced muscle damage in mice. However, the efficacy in humans is unknown. Further, poor solubility and rapid metabolism of standardized curcumin may limit potential benefits. CurcuWIN®, a novel curcumin formulation containing 20% curcuminoids (CUR), demonstrates a 45.9 fold greater absorption over standard curcumin. Therefore, the current study sought to examine the effect of differing doses of a novel form of curcumin on performance decrements following downhill running, a known exercise type to result in muscle damage. Sixty‐two moderately trained men and women (21±2 y; 70.0±13.7 kg; 169.3±15.2 cm; 25.6±14.3 BMI) were randomly assigned to ingest 50 mg CUR (in the form of 250 mg CurcuWIN®), 200 mg CUR (in the form of 1,000 mg CurcuWIN®), or placebo (PLA; corn starch) for eight weeks in a double‐blind, randomized, placebo controlled parallel design. At the end of the eight week supplementation period subjects completed a muscle damaging exercise protocol, downhill running. Muscle function, isokinetic peak flexion and extension, was assessed prior to and 1 h, 24 h, 48 h, and 72 h post downhill run. Standardized magnitude based inference was used to define outcomes. As evidence of the exercise bout inducing performance decrements, clear negative contrasts on performance were observed in both the PLA and low dose CUR at 1 h (mean pre post difference range; ±SD range) (extension, −13 to −18; ±5.9 to 7.9 ft‐lbs; flexion, −5 to −6; ±2.2 to 2.6 ft lbs) and 24 h (extension, −10 to −11; ±6 ft‐lbs; flexion, −4 to −6; 3 ft‐lbs) post‐downhill run. High dose CUR attenuated performance decrements, as evidenced by a lack of clear contrasts at 1 h (extension, −8; ±4 ft lbs; flexion −4; ±2 ft‐lbs) and 24 h (extension, −6; ±6 ft‐lbs; flexion, −3; ±3 ft‐lbs). Given the lack of clear contrasts, these data suggest that high dose bioavailable curcumin (200 mg CUR) attenuates performance decrements following downhill running, eccentric loading, which may improve subsequent adaptations to chronic training. Further study is warranted in other exercise types (i.e. resistance training) and chronically.Support or Funding InformationThis study was supported by OmniActive Health Technologies Ltd., Mumbai, India