Purpose: To estimate the energy expenditure (EE) of Vinyasa Flow and validate the Actigraph (AG) and GENEActiv (GA) for measuring EE in Vinyasa Flow. Methods: Participants (N = 22) were fitted to a mask attached to the Oxycon. An AG was placed on the left hip and a GA was placed on the non-dominant wrist. Participants were randomized to an initial resting activity before completing a 30-minute Vinyasa Flow video. AG data was scored using the Freedson VM3 (2011) and the Freedson Adult (1998) algorithms in the Actilife software platform. EE from GA were derived using cut points from a previous study. Date and time filters were added corresponding to the time stamps recorded by the tablet video files of each yoga session. Kcals and METs expended by participants were calculated using bodyweight measured during their visit. Data was analyzed using SPSS. A dependent samples t-test, an intraclass correlation coefficient (ICC), and mean absolute difference were used to determine agreement between variables. Results: According to the Oxycon, participation in Vinyasa Flow required an average EE of 3.2 ± 0.4 METs. The absolute agreement between the Oxycon, AG, or GA was poor (ICC < .20). The mean difference in METs for the AG was −2.1 ± 0.6 and GA was −1.4 ± 0.6 (all p < .01). Conclusion: According to the Oxycon, participation in Vinyasa Flow met the criteria for moderate-intensity physical activity. The AG and GA consistently underestimated EE. More research is needed to determine an accurate measurement for EE during yoga using a wearable device appropriate for free-living environments.