( ( ( Creates stimulus ) ( for ( muscle building ) ) ) . )
(ROOT (NP (NP (JJ Creates) (NN stimulus)) (PP (IN for) (NP (NN muscle) (NN building))) (. .)))
Creates stimulus for muscle building.
(ROOT (S (NP (NNS Muscles)) (VP (VBP need) (NP (NN stimulus)) (PP (TO to) (NP (NN contract)))) (. .)))