Your diaphragm is the engine of your voice, but it's involuntary. You can't flex it like a bicep. This makes "support" feel abstract and confusing.
The panting dog exercise bypasses that confusion by tapping into a primal reflex. Just like a dog pants to cool down, you can use rapid, shallow breaths to wake up your diaphragm and surrounding muscles. That bouncing sensation is the physical foundation of a supported voice.
The Sound
Breathy "Huh" sounds. Short, light, and airy, like a panting dog but with a specific pitch. Think "Huh-Huh-Huh-Huh."
The Feel
Stick your tongue slightly out (relaxed, not tense) to keep your airway open. Focus entirely on your upper belly (epigastrium). Feel it bouncing in and out rapidly.
The Drill
This moves fast. Keep the "Huh" sounds short and disconnected. If you get dizzy, stop immediately and take a slow breath.
Why This Works
When you pant, your body forces the diaphragm to contract and relax rapidly. This gives you immediate feedback on where your diaphragm is and what it feels like when it's moving. It also increases blood flow to your support muscles, waking them up before you sing sustained phrases.