Effects of Zembrin® (Sceletium tortuosum) Supplementation on Mood, Soreness, and Performance Following Unaccustomed Resistance Exercise: A Pilot Study

Abstract

The purpose of this study was to investigate acute Zembrin® (Sceletium tortuosum) supplementation on muscle soreness, markers of muscle damage, mood, and exercise performance following unaccustomed resistance exercise. Untrained females (n = 16) were divided into two groups with a different three-day treatment regimen: (1) placebo (PL) and (2) Zembrin® (ZEM). During the initial visit, baseline perceived soreness, range of motion (ROM), mood state (profile of mood states (POMS) questionnaire), and plasma lactate dehydrogenase concentrations (LDH) were measured followed by the performance of an eccentric bicep curl protocol with their non-dominant arm. The total repetitions and rate of perceived exertion (RPE) were recorded throughout the exercise. The participants then supplemented with the corresponding treatment immediately following, the subsequent day, and 30 min prior to completing a 48 h follow-up visit. For the 48 h visit, all procedures were repeated and comparisons were drawn for perceived soreness, ROM, LDH, mood scores, total repetitions, and RPE. The findings indicate that short-term ZEM supplementation resulted in lower perceived soreness (p = 0.020) and a greater preservation of ROM (p = 0.028) at 48 h versus the PL group. Mood worsened from the baseline to 48 h regardless of the treatment (p = 0.043) but the decrements were exacerbated in the PL group compared with the ZEM group (p < 0.001). LDH levels (p = 0.019) and RPE (p = 0.008) were higher and total repetitions were lower (p < 0.001) at 48 h irrespective of the treatment. Although short-term dietary enrichment with ZEM did not alter the exercise performance or biomarkers of muscle damage, the current results suggest ZEM supplementation may be effective in reducing the markers of soreness and preserve mood following unaccustomed eccentric exercise.