Background: Patients with chronic obstructive pulmonary disease (COPD) might suffer from severe dyspnea, which importantly impacts on the performance of activities of daily living (ADL). Patient training of energy conservation techniques (ECTs) might be useful to improve the tolerance and execution of these ADL, but objective studies evaluating the effect of teaching ECTs on the metabolic equivalent of task (MET) in patients with COPD are sparse. Objectives: The aim of this study was to test the hypothesis that practicing ECTs after a 2-week ECT teaching period would reduce the energy expenditure (MET) in performing an activity in patients with severe COPD. Methods: Energy expenditure was assessed with a gas exchange system (OxyconTM Mobile) during one out of five standardized ADL before and after a 2-week intervention period in which ECTs were taught. These ECTs comprised a good breathing technique, an ergonomic way of performing the activity, and the use of assistive devices. Results: Thirty-two patients with COPD (mean FEV1: 39 ± 14%; female: n = 18; age: 68 ± 7 years) were included. A significantly lower MET (2.3 ± 0.6 to 2.1 ± 0.5; p < 0.05) and less desaturation (89.7 ± 5.2 vs. 91.1 ± 5.5% HbO2; p < 0.05) were seen while performing the same activity after the intervention. However, there was no significant difference in the time spent on the task performed (6.0 ± 3.9 vs. 6.7 ± 4.0 min; p > 0.05). Conclusions: A 2-week educative program on ECTs successfully reduces the energy spent for performing ADL relevant to the patient without any significant increase in the time spent on the activity.