Regular physical activity (PA) is an important concept to measure in health education research. The health education researcher might need to measure physical activity because it is the primary measure of interest, or PA might be a confounding measure that needs to be controlled for in statistical analysis. The purpose of this commentary is to describe the methods and approaches for measuring physical activity that are most appropriate to health education evaluation and research. The researcher can select from objective approaches (e.g., direct observation, accelerometers) that are more precise in measuring physical activity or subjective approaches (e.g., logs, interviews, surveys) that are more practical in terms of administration but are inherently more imprecise due to sources of recall error related to self-report.