Thomas' confession after he put his hand in Jesus' side after the resurrection indicates it was bodily.
This body also was able to pass through walls, as in the upper room. Thus, only appearing to believers, and avoiding the Roman soldiers would not have been hard to do.
The effects of sin that Adam brought in did not just affect the spirit of but also the body. Thus the reason why we all die. Our spirits are dead to the things of God and our bodies are dead to immortality. The resurrection body of Christ not only proved that the consequences of sin on the spirit have been redeemed but also that the consequences of sin on the body has been redeemed.
If the body does not overcome death, then sin still has the power over it. On the contrary, Paul writes that Christ has conquered sin. "Oh death, where is thy victory? Where is thy sting? Read 1 Corinthians 15.
Or that what Thomas experienced was identically the same as if it had been.