I use this technique everywhere. Light touch when applied over the origin of weakness or pain can improve muscle output. This also indicates where treatment should be applied for a more effective and faster result.
Study: A spatiotemporal signature of cortical pain relief by tactile stimulation: An MEG study.
"The present study clearly demonstrated pain relief by tactile input at the spinal and cortical level, showing the spatiotemporal signature of tactile-induced analgesia. Pain–tactile interaction at the cortical level was investigated using carefully timed sensory modality-specific stimuli, in combination with cortical source-based neuromagnetic analysis. We were able to clearly distinguish source location from pain and tactile inputs associated with natural-touch like sensation. Our study clearly demonstrates that the spatial feature of cortical modulation by nociceptive input was different compared with spinal modulation."