We investigate the influence of two attitude estimation methods for human posture detection. In the context of ADL (i.e. Activities of Daily Living) we analyze inertial sensors to reveal uncomfortable situations. Quantifying postures such as standing up, walking, lying down or sitting may feature people autonomy and well being. We report comparisons between two main attitude estimation strategies. Our experimental protocol uses a precise ground truth obtained from two annotators. The dataset involves 9 participants and provides 50 various data sequences. We discuss the obtained promising results, analyze advantages and limits when using attitude estimation in this context.