Acute effect of Snus on physical performance and perceived cognitive load on amateur footballers

Smokeless tobacco (Snus) is a substance that contains nicotine, which has been placed on World Anti-Doping Agency’s 2014 Monitoring Program. A proliferation of nicotine use in sport has been observed in recent years, but little is known regarding its effects, especially on foot- ball players’ performance. Therefore, the aim of this study was to assess the effect of Snus on physical perfor- mance, heart rate variability, subjective activation, mental fatigue, and perceived readiness before a physical test in non-smoker, non-Snus user, amateur football players. Participants were administered either Snus or placebo 40 min prior to a fitness test battery (handgrip test, countermovement jump, agility test, and Yo-Yo intermittent recovery test). Results showed that Snus intake (compared with placebo) increased perceived mental fatigue level and mental load, and reduced per- ceived readiness level and heart rate variability. No significant differences between the two experimental con- ditions were found in either performance in the physical tests or perceived physical fatigue levels. In light of these results, Snus could not be considered an ergogenic sub- stance. On the contrary, based on the extant evidence linking mental load and fatigue with physical perfor- mance, we argue that the observed negative effects on mental fatigue, perceived readiness, and heart rate vari- ability should be considered.