Fiber Type-Specific Responses to Perceptions of Delayed Onset Muscle Soreness with Astaxanthin Supplementation

Abstract

1182 PURPOSE: To determine the effects of astaxanthin anti-oxidant supplementation as a counter-measure for delayed onset muscular soreness (DOMS) in currently trained individuals, nine weight trained males (X ± SE: age = 25.1 ± 1.6 yrs., hgt = 1.79 ± 0.02 m, wgt = 86.8 ± 4.4 kg) participated in this study. METHODS: All subjects provided muscle biopsy samples from the vastus lateralis m. prior to inducing DOMS in the knee extensor mm. (10 sets × 7–10 reps, 85% eccentric 1 RM). The subjects ingested either 8 g.d-1 of astaxanthin (Suppl; n = 4) or a placebo (Con; n = 5) for a 3 week loading phase prior to the DOMS-inducing protocol, and during a 12 d recovery phase. Perceptions of DOMS at 48 hrs post-eccentric exercise were quantified by muscle soreness ratings (0–7 Likert scale). Muscle fiber characteristics were determined via mATPase histochemistry and digital imaging to determine % cross-sectional areas of the major fiber types (I, IIA, IIAB/B). Due to small numbers of IIB fibers in some subjects, IIAB hybrid fibers were included in this fiber type population. Simple regression was used to determine relationships between fiber characteristics and perceptions of soreness. RESULTS: No differences in perceptions of soreness between the Suppl or Con groups were observed (p>0.05), with all subjects exhibiting a mean score of >5. Percent fiber type areas were similar (p>0.05) for both groups (type I, Suppl = 47.6 ± 8.9%, Con = 41.3 ± 2.7%; type IIA, Suppl = 44.3 ± 5.6%, Con = 53.0 ± 2.8%; type IIAB/B, Suppl = 8.2 ± 3.6%, Con = 5.7 ± 1.6%). However, 48 hrs after the DOMSinducing session, perceptions of soreness for the Suppl group were positively related to % area type I (r = 0.90), and negatively related to % area types IIA (r = −0.80) and IIAB/B (r = −0.99). A distinctly different correlational pattern was observed for the Con group (% type I area, r = −0.40; % type IIA area, r = 0.03; % type IIAB/B area, r = 0.62). CONCLUSIONS: Collectively, these preliminary data suggest that astaxanthin supplementation may preferentially attenuate perceptions of DOMS in weight trained men with a high % area for fiber types IIA & AB/B. Supported by a Grant from Cyanotech Corp.