Manual assessment of muscular function, in particular a method known as applied kinesiology (AK), is a clinical measure of neurologic function. A review of the literature reveals methodological problems with previous studies of AK as a form of neurologic assessment. Research designs that do not reflect clinical practice and principles of AK are common in the literature. Additional study is warranted to explore the potential of AK manual muscle testing as a diagnostic tool. We outline principles of AK and recommend that future research reflect more accurately the clinical practice of functional neurologic assessment and applied kinesiology.