Better and Gaining strength

Better adjective - (comparative of `good') superior to another (of the same class or set or kind) in excellence or quality or desirability or suitability; more highly skilled than another.

Gaining strength and better are semantically related. In some cases you can use "Gaining strength" instead an adjective "Better".

Better and gaining strength are semantically related. Sometimes you can use "Better" instead an adjective phrase "Gaining strength".