These healing reactions are good detox. When you use your hands to Paida yourself and/or others, your hands are being slapped as well. It is a real win-win exercise. Sha, cracks, blood or watery blisters on the palms are healing reactions, indicating blockages in the Heart and Pericardium Meridians, and problems with the heart. It also shows that the self-healing mechanism is working to remove the blockages. Continue to slap, the blisters will break, blood and fluid will seep out, and the wound and heart disease will heal naturally.