have no staying power

to lack endurance; not to be able to last. Sally can swim fast for a short distance, but she has no staying power. That horse can start fairly fast, but it has no staying power.

Common Names:

Name	Pronounced	Usage
Uzma	-	Arabic
Lilac	LIE-lək	English (Rare)
Jeong-Suk	jung-sook	Korean
Gethin	-	Welsh
Priska	-	German, Biblical Greek
Isaurus	-	Late Roman