<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Much of the empirical research on the effectiveness of different instructional designs has focused on declarative tasks, where a learner acquires knowledge about a certain topic. It is unclear to what extent findings for learning declarative tasks (which are not consistent on all aspects) carry over to learning procedural tasks, where a learner acquires a certain skill. In this paper, we describe an experiment studying a specific kind of procedural instructions, namely exercises for the prevention of repetitive strain injury (RSI), taking information modality (text versus picture versus film clip) and difficulty degree of the exercises (easy versus difficult) into account. In the experiment, participants had to learn RSI exercises and were asked to execute them. The results showed that an instruction in a picture lead to the shortest learning times followed by an instruction in a film clip. An instruction in text led to the longest learning times. For the amount of practicing the exercises during the learning phase, it was found that the participants in the film clip condition hardly engaged in practicing the exercises during the learning phase. The participants in the picture condition engaged in a moderate amount of practicing of the exercises during the learning phase. The participants in the text condition engaged in the most practicing during the learning phase. The results concerning the execution times showed that an instruction in a picture led to the lowest execution times followed by an instruction in a film clip. The instruction in text led to longest execution times. Finally, for the amount of correctly executed exercises, it was found that learning from a film clip led to the highest learning performance, both for easy and for difficult exercises. Learning from an instruction in text led to a fairly good learning performance, both for easy and difficult exercises. Learning from a picture led to a good learning performance for the easy exercises, but the performance dropped for the difficult exercises. </para>