1 The placebo and nocebo effects on peak minute power during incremental arm

34 This investigation aimed to explore the effects of inert sugar free drinks described as 35 either ‘performance enhancing’ (placebo) or ‘fatigue inducing’ (nocebo) on peak 36 minute power (PMP;W) during incremental arm crank ergometry (ACE). Twelve 37 healthy, non specifically trained individuals volunteered to take part. A single blind 38 randomized controlled trial with repeated measures was used to assess for differences 39 in PMP;W and oxygen uptake, heart rate, minute ventilation, respiratory exchange 40 ratio, and subjective reports of local (LRPE) and central (CRPE) ratings of perceived 41 exertion, between three separate, but identical ACE tests. Participants were required 42 to drink either 500ml of a ‘sports performance’ drink (placebo), a ‘fatigue inducing’ 43 drink (nocebo), or water prior to exercise. The placebo caused a significant increase in 44 PMP;W, and a significant decrease in LRPE compared to the nocebo (p=0.01; 45 p=0.001) and water trials (p=0.01). No significant differences in PMP;W between the 46 nocebo and water were found. However, the nocebo drink did cause a significant 47 increase in LRPE (p=0.01). These results suggest that the time has come to broaden 48 our understanding of the placebo and nocebo effect and their potential to impact 49 sports performance. 50 51