The goal of this research is to show how swim coaches adapt themselves to an activity-stop condition (Covid-19 lockdown). This is a work psychology intervention based on a French-specific clinical approach to activity (Clot, 1999, 2008), with major references to Lev Vygotsky’s historical-cultural theory. Eight swim coaches were monitored during the Covid-19 2021 lockdown in France. One of them found an original solution to keep in touch with his swimmers and “practice” through videoconferences: dry land training, swimming-related theoretical courses and swim champions video analysis. The development of this activity had been documented for two months, with observations, video recording and interviews, all in teleconference. It resulted in a visual elaboration of a three-poles activity model, in order to show how changing an instrument (from pool to videoconference software) can lead up to a new activity. In a regular swim coach activity, the three-poles model is Subject (S)-Swim coach, Object (Ob)–Swim practice and Others (O)-Swimmers. These three poles are linked to each other through direct and instrument-mediated relations. Pool is the instrument (I). As pool became unavailable, a new instrument is discovered: (I’)-videoconference software. So, the three poles shift to new places and became: (S’)-Teacher, (Ob’)-Staying in touch with swimming, (O’)-Pupils. Some back-and-forth tensions exist between the former and the present activity, partly in an active form (“Going towards new activity”) and partly in a passive form (“Going back to former activity”). The French clinical approach to activity identifies these tensions with Spinoza’s affectus. In the end passive form wins, as swimming practice become available again and because this is the more stabilized and grounded of the two activities. A psychological intervention without direct interaction is problematic for some aspects as body language detection. Nevertheless, this form of intervention was completely coherent with context, because psychologist and subjects were in similar work conditions and this allowed a grounded analysis. This research showed how a new activity could rise from a hampered one. This process is formalized through the French clinical approach three-poles model. Pursuing this kind of research could help understand how professionals, in contexts such the Covid-19 pandemic, find out unexpected ways to pursue their work.