diff --git a/include/config/config_movement.h b/include/config/config_movement.h
index ae4e36cfb..882ae3b97 100644
--- a/include/config/config_movement.h
+++ b/include/config/config_movement.h
@@ -73,11 +73,6 @@
  */
 // #define PREVENT_CAP_LOSS
 
-/**
- * Enables Platform Displacement 2, also known as momentum patch. Makes Mario keep the momemtum from moving platforms.
- */
-#define PLATFORM_DISPLACEMENT_2
-
 /**
  * Uses Shindou's pole behavior.
  */
@@ -136,3 +131,14 @@
  */
 // #define BUGFIX_DIALOG_TIME_STOP
 
+/**
+ * Enables Platform Displacement 2, an upgrade to the physics involving moving platforms and how Mario interacts with them.
+ */
+#define PLATFORM_DISPLACEMENT_2
+
+/**
+ * Inertia defines; allow Mario to preserve his momemtum when leaving moving platforms.
+ * These require Platform Displacement 2 to be enabled.
+ */
+#define MARIO_INERTIA_UPWARD
+// #define MARIO_INERTIA_LATERAL
diff --git a/src/game/platform_displacement.c b/src/game/platform_displacement.c
index 4b43f7290..ae5053431 100644
--- a/src/game/platform_displacement.c
+++ b/src/game/platform_displacement.c
@@ -179,11 +179,16 @@ static u8 sInertiaFirstFrame = FALSE;
  * Apply inertia based on Mario's last platform.
  */
 static void apply_mario_inertia(void) {
+#ifdef MARIO_INERTIA_UPWARD
     // On the first frame of leaving the ground, boost Mario's y velocity
     if (sInertiaFirstFrame) {
-        gMarioState->vel[1] += sMarioAmountDisplaced[1];
+        if (sMarioAmountDisplaced[1] > 0.0f) {
+            gMarioState->vel[1] += sMarioAmountDisplaced[1];
+        }
     }
+#endif
 
+#ifdef MARIO_INERTIA_LATERAL
     // Apply sideways inertia
     gMarioState->pos[0] += sMarioAmountDisplaced[0];
     gMarioState->pos[2] += sMarioAmountDisplaced[2];
@@ -191,6 +196,7 @@ static void apply_mario_inertia(void) {
     // Drag
     sMarioAmountDisplaced[0] *= 0.97f;
     sMarioAmountDisplaced[2] *= 0.97f;
+#endif
 
     // Stop applying inertia once Mario has landed, or when ground pounding
     if (!(gMarioState->action & ACT_FLAG_AIR) || (gMarioState->action == ACT_GROUND_POUND)) {