Purpose – The purpose of this paper is to explore in what way gradually increasing teachers’ theory-based instruction affects the students’ learning outcomes, illustrated by the example of learning how to regulate body tension in the upper secondary school.

Design/methodology/approach – In total, 72 students from four classes participated in the study. The way the students were offered to understand “regulation of tension” was designed by variation theory, and the method used was learning study, an iterative process whereby the results from the first lesson are the basis for the design of the next implementation in a new group of students.

Findings – There is a significant increased learning outcome in all four lessons, but in Lesson D, where the highest increase (129 percent) was found, all students improved their results. The use of the theoretical framework had effect on the teachers to vary only the most important aspects in the instruction in the last cycle, where the features chiselled out during the study (e.g. heart rate, respiration, muscle tension) were contrasted more clearly, which had an impact on the students’ learning. Based on the theoretical framework, the teachers got more skilled at experiencing what should vary and what should be kept invariant in order to facilitate the students’ learning. In the last intervention, the teachers found one pattern of variation which was more powerful than the previous. In this one, the physical activities were kept invariant, but different responses of the sympathetic nervous system were contrasted, one at a time, to establish knowledge of different bodily responses to tension.

Originality/value – Learning study has mainly been used in subjects such as Mathematics or other theoretical issues but this paper describes in what way learning study can be used in PE. So second, the result of this study contributes to knowledge about how students’ learning outcome in PEH can increase by directing focus on an object of learning rather than actual learning activity. The object of learning in this study is to learn to regulate tenseness and the learning outcomes have been analyzed in the perspective of variation theory.