“…Specifically applied to emotional states (i.e., embodied emotion), manipulating the bodily expression of an emotion (e.g., facial expression) can influence how emotional information is processed and may be accompanied by self-reports of the corresponding emotion (e.g., Niedenthal, 2007;Niedenthal, Mermillod, Maringer, & Hess, 2010). Thus, simulated frowning may prime unpleasant feelings (e.g., Larsen, Kasimatis, & Frey, 1992) and, in contrast to relaxation, increase activation and muscle tension which may, in turn, reduce RE (e.g., Martin, Craib, & Mitchell, 1995). Furthermore, frowning muscle activity, termed the 'face of effort', has shown a moderate-to-strong positive relationship with effort perception during physical tasks (de Morree & Marcora, 2010).…”