Why is muscular endurance important for table tennis players

For a table tennis player, endurance is the quality that allows him to sustain a high speed over the couple of top spin strokes with high rotation of the ball. This quality is muscle endurance, the ability of the shoulder muscle group to sustain high-intensity, repetitive movement.

Explanation:

you may having too much sleep.. a good night sleep consists of about 7 hours. more than that could be the reason you're still tired throughout the day.