Core material

The core is the foam block that fills the racket head behind the face, and it is the spring in the system. When the ball hits, the core compresses and gives the energy back. How much it compresses, and at what impact speed, is the difference between a racket that helps a slow swing and one that rewards a fast one.

EVA and FOAM

EVA (ethylene-vinyl acetate) is the standard: a rubber foam that brands mix at different densities, from soft through medium to the hard compounds sold under names like Black EVA or EVA Pro. It holds its shape well and keeps its response consistent over the racket's life. FOAM (a softer polyethylene foam) sits below soft EVA on the density scale: more compression, more rebound at low impact speed, a plusher feel, and a shorter life, since a very soft core packs down faster with heavy use.

Soft versus hard is really slow versus fast

The useful way to read core density is by swing speed. A soft core compresses under a gentle impact, so a defensive lob or a tired third-set block still comes back deep: the racket contributes energy the swing did not. A hard core barely moves at that speed and the ball drops short. Reverse the situation and the ranking flips. Swing hard into a soft core and it bottoms out, mushy and vague; swing hard into hard EVA and it returns the energy with interest, plus the exact, connected feedback that makes fast net exchanges readable. Comfort follows the same line. Soft cores absorb impact shock, hard cores pass it to the elbow.

Choosing a density

• Soft EVA or FOAM: beginners, defensive players, anyone managing arm pain. Free depth and a muted impact.
• Medium EVA: the club-player default. Response across the whole speed range without a harsh word for the arm.
• Hard EVA: fast swings and attacking games. Maximum return on the smash, nothing given away for free.

The core never acts alone. The face sheet in front of it flexes first, and the pairing decides the racket's character: fiberglass over soft foam is the comfort end of the spectrum, carbon over hard EVA the performance end. Judge the sandwich, never one layer.