A syntactic metal foam composite that is substantially fully dense except for syntactic porosity is formed from a mixture of ceramic microballoons and matrix forming metal. The ceramic microballoons have a uniaxial crush strength and a much higher omniaxial crush strength. The mixture is continuously constrained while it is consolidated. The constraining force is less than the omniaxial crush strength. The substantially fully dense syntactic metal foam composite is then constrained and deformation worked at a substantially constant volume. This deformation causes at least work hardening and grain refinement in the matrix metal. The resulting deformed syntactic metal foam composite has an energy absorption capacity that is at least 1.5 to 2 or 3 times or more the energy absorption capacity of the precursor substantially fully dense syntactic metal foam composite.