Embodiments of the present disclosure describe a method of monitoring a patient comprising generating an accelerometer signal of a patient via a patient medical device and capturing and sampling the accelerometer signal at a sampling rate that utilizes non-regular timing intervals. Embodiments further describe a patient medical device comprising sensors for monitoring an accelerometer signal of a patient and circuitry for sampling the accelerometer signal at a sampling rate that utilizes non-regular timing intervals. Embodiments also describe a method of processing physiological signals comprising monitoring ECG signals and accelerometer signals of a patient via a patient medical device and capturing an ECG segment and sampling the accelerometer signal at a sampling rate that utilizes non-regular timing intervals.