A Hitchhiker’s Guide to Physical and Cognitive Effort

Effort is integral to the regulation of behavior. It can be central for achieving goals in a range of activities, including sports, exercise, learning, and work. For centuries, researchers have tried to understand what effort is and how it shapes human behavior. Yet, despite its importance, there is no overarching consensus on what effort represents and how it should be measured. Attesting to this, academic disciplines conceptualize and measure effort in strikingly different ways. While this highlights the multitude of factors relevant to understanding effort, it has also led to siloed approaches, making interdisciplinary integration challenging. To facilitate interdisciplinary exchange, this guide aims to provide a descriptive and impartial overview of frequently used effort conceptualization and proxies. We first review three prominent conceptualizations of effort: force-based, resource-based, and mediation-based accounts. Second, we present a broad overview of commonly used effort proxies, reflecting changes in one system: neurophysiological, metabolic, psychological, and behavioral output. For each, we provide a brief review of properties, applications, and limitations relevant to effort-related research. With this approach, our aim is not to resolve disciplinary differences by pitting the utility of different conceptualizations and proxies against each other. Rather, we aim to provide a shared conceptual framework on which more integrative theorizing and cumulative progress in effort research can be achieved across disciplines.