There's up to 10% more muscle activity in the decline version versus the flat version. More muscle activity means more muscle fiber recruitment. That means more fibers are stimulated to grow. This might be in part because the triceps are stretched more. The muscle being stretched the most is often the muscle recruited the most.
The decline version is also more effective at isolating the triceps because the shoulders are taken out if the equation – they tend to compensate in flat variations. And the decline position places the triceps under tension for a greater range of motion and more optimal loading.
related posts
Rolling the bar, keeping the chin up, and other tips towards getting a mighty big pull.
If you don't compete in powerlifting, do you still need to deload? Yes, if you train hard. Here's why and what to do.
It seems like you've been adding weight to the stack each time you do triceps pushdowns. The veins in your neck stick out like a garden hose as you power through the sticking point, and the cable starts cutting into your neck, just like your idol, Tom Platz. You stop, however, before it cuts through and leaves a bloody mess on the floor.
High Stimulation Training Methods for Enhanced Growth