||We demonstrate that simple, unobtrusive sensors attached to the lower arm can be used to capture muscle contractions during specific hand and arm activities such as grasping. Specifically, we investigate the use of force sensitive resitors and fabric stretch sensors, which can both be easily integrated into clothing. We use the above sensors to detect the contractions of arm muscles. We present and compare the signals that both sensors produce for a set of typical hand actions. We finally argue that they can provide important information for activity recognition.