The aims of this study were to identify specific physical education in content and language integrated learning (PE-in-CLIL) teaching strategies that improve oral communication and to check that meaningful improvements occur in both oral comprehension and oral interaction. Action research (AR) was chosen because teaching practice can be improved during such research. Elliot's practice model was used as the basis for the study. The participants were 26 primary education pupils aged 10-11. Data were gathered from teacher diaries and video recordings, and analysed at three levels. Complementation and triangulation techniques were used to integrate evidence and thus to answer AR questions. There were significant improvements in oracy using the PE-in-CLIL approach. In addition, specific teaching strategies that improve oral communication were identified. This study therefore demonstrates how a PE-in-CLIL programme can be used not only to enhance oracy, but also to improve teaching.