It is called the Paschal Fast.
According to the United States bishops, "If possible, the fast on Good Friday is continued until the Easter Vigil (on Holy Saturday night) as the "Paschal Fast" to honor the suffering and death of the Lord Jesus, and to prepare ourselves to share more fully and to celebrate more readily his resurrection."
One thinks of great painters or composers who are so caught up in a particular work they think of nothing else, not even food. Traditionally, the Paschal Fast was a radical fast. The only food and drink was the Eucharistic bread and wine.
- Little Black Book, Diocese of Saginaw