Lectures constitute a basic component of physiology instruction in scientific and healthcare curricula. Technological progress has allowed a switch from face to face to video lectures, yet there is no evidence of video efficacy in physiology. Because videos increase the cognitive load during a learning task, identifying tools that decrease students' cognitive load during video lectures is critical. Segmenting videos with pauses and inducing joint attention with eye movement modeling examples (EMME) could reduce the cognitive load and improve second-year medical students' learning in physiology video lectures. Second-year medical students were randomized into four groups [EMME þ pauses (EMME þ P), EMME without pause`s (EMME-NoP), pauses only (NoEMME þ P), and no EMME and no pause (NoEMME-NoP)], took pretest quizzes, watched a renal physiology video lecture, and answered a cognitive load questionnaire and posttest quizzes on the Moodle learning management system. Student prior knowledge was assessed by a pretest, and learning gains were assessed by the difference between posttest and pretest scores. One hundred ninety-five students completed the experiment. Pauses improved learning gains (P < 0.01) but not EMME (P = 0.11). Student prior knowledge has several interactions with other variables: low-prior knowledge students obtained better learning gains (P < 0.001) and high-prior knowledge students had lower learning gains with EMME (P < 0.05). Our study shows the potential role of tools designed to reduce students' cognitive load during a renal physiology video lecture and the critical need for empirical validation of pedagogical solutions that are adapted to the specificities of physiology lectures.