The calves and Achilles tendon are tissues that function more like rubber bands. They work by holding tension and reacting to whatever force that is put on them. This means the kind of load they take is almost exclusively eccentric.
Primary power comes from the glutes/hips. The musculature in the hips are far far more efficient at producing concentric force. Your heel cords should thus be able to absorb force as your foot strikes the ground, come to a stop, and rebound autonomously like pulling a rubber band and letting it go.
When I was a rookie athlete, i was a “calf runner”. I thought the deliberate push using the calves produced power. That got me into a lot of foot problems and shin splints and lousy performance. Making my hips do the real work and letting my heels cords rebound was a far more efficient pattern and use of biomechanics.
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