Effects of Acute Mistletoe (Viscum album L.) Ingestion on Aerobic Exercise Performance

Mistletoe (Viscum album L.; VA) has been traditionally used in folk medicine to combat fatigue and stress. Evidence has shown that chronic consumption of VA results in an enhancement of oxidative metabolism and exercise performance. However, no studies have investigated how acute VA consumption influences performance. The purpose of this brief report was to investigate the effects of acute VA ingestion on rowing exercise performance. Physically active females were recruited for this study. In a crossover, counterbalanced design, participants completed two trials each with a different treatment: (1) VA (2000 mg) and (2) placebo (PL; gluten-free cornstarch; 2000 mg). A total of 30 minutes prior to exercise, participants consumed their treatment. The participants were familiarized with the rowing ergometer and warmed up for 5 min at 50% of age-predicted heart rate max. Immediately following the warm-up, the participants completed a 2000 m rowing time trial. Blood lactate (La) was obtained with a lactate meter via finger prick before and after exercise. Power output, trial time, heart rate, rating of perceived exertion (RPE), and La were analyzed. The findings revealed no significant differences for the relative power output (p = 0.936), trial time (p = 0.842) or heart rate (p = 0.762). Rating of perceived exertion was lower with VA ingestion (p = 0.027). La was significantly higher post-exercise regardless of treatment (p < 0.001). However, post-exercise La was lower with VA ingestion (p = 0.032). Findings do not support VA as an ergogenic aid but suggest ingestion may alter metabolism resulting in less La formation and subjective fatigue.