diff --git a/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PhysicsConstraint.java b/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PhysicsConstraint.java
index 322e42a60..310bede29 100644
--- a/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PhysicsConstraint.java
+++ b/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/PhysicsConstraint.java
@@ -197,7 +197,7 @@ public class PhysicsConstraint extends Constraint<PhysicsConstraint, PhysicsCons
 							m = t * p.massInverse;
 							e = p.strength;
 						}
-						float ax = p.wind * skeleton.windX - p.gravity * skeleton.gravityX;
+						float ax = p.wind * skeleton.windX + p.gravity * skeleton.gravityX;
 						float ay = p.wind * skeleton.windY + p.gravity * skeleton.gravityY;
 						float rs = rotateOffset, ss = scaleOffset, h = l / f;
 						while (true) {