The ornamental design for a wearable muscular strengthaid apparatus, as shown and described.
1. Wearable muscular strength aid apparatus
1.1 : Perspective
1.2 : Front
1.3 : Back
1.4 : Left
1.5 : Right
1.6 : Top
1.7 : Bottom
The broken lines depict portions of the wearable muscular strength aid apparatus that form no part of the claimed design; the fine lines on the drawings indicate the flat surface or curved surface; reproduction 1.1 is a front perspective view of the wearable muscular strength aid apparatus; reproduction 1.2 is a front view thereof; reproduction 1.3 is a back view thereof; reproduction 1.4 is a left view thereof; reproduction 1.5 is a right view thereof; reproduction 1.6 is a top view thereof; and reproduction 1.7 is a bottom view thereof; this is a design for a wearable muscular strength aid apparatus made of textile, synthetic resign and metal; the claimed design supports the hip and spine.