diff --git a/src/app/api/cron/garmin-sync/route.test.ts b/src/app/api/cron/garmin-sync/route.test.ts
index d92e636..a978f91 100644
--- a/src/app/api/cron/garmin-sync/route.test.ts
+++ b/src/app/api/cron/garmin-sync/route.test.ts
@@ -23,6 +23,7 @@ vi.mock("@/lib/pocketbase", () => ({
       }),
       create: mockPbCreate,
       update: mockPbUpdate,
+      authWithPassword: vi.fn().mockResolvedValue({ token: "admin-token" }),
     })),
   })),
 }));
@@ -133,6 +134,8 @@ describe("POST /api/cron/garmin-sync", () => {
     mockDaysUntilExpiry.mockReturnValue(30); // Default to 30 days remaining
     mockSendTokenExpirationWarning.mockResolvedValue(undefined); // Reset mock implementation
     process.env.CRON_SECRET = validSecret;
+    process.env.POCKETBASE_ADMIN_EMAIL = "admin@test.com";
+    process.env.POCKETBASE_ADMIN_PASSWORD = "test-password";
   });
 
   describe("Authentication", () => {
@@ -159,6 +162,26 @@ describe("POST /api/cron/garmin-sync", () => {
 
       expect(response.status).toBe(401);
     });
+
+    it("returns 500 when POCKETBASE_ADMIN_EMAIL is not set", async () => {
+      process.env.POCKETBASE_ADMIN_EMAIL = "";
+
+      const response = await POST(createMockRequest(`Bearer ${validSecret}`));
+
+      expect(response.status).toBe(500);
+      const body = await response.json();
+      expect(body.error).toBe("Server misconfiguration");
+    });
+
+    it("returns 500 when POCKETBASE_ADMIN_PASSWORD is not set", async () => {
+      process.env.POCKETBASE_ADMIN_PASSWORD = "";
+
+      const response = await POST(createMockRequest(`Bearer ${validSecret}`));
+
+      expect(response.status).toBe(500);
+      const body = await response.json();
+      expect(body.error).toBe("Server misconfiguration");
+    });
   });
 
   describe("User fetching", () => {
diff --git a/src/app/api/cron/garmin-sync/route.ts b/src/app/api/cron/garmin-sync/route.ts
index 930c52d..3410da1 100644
--- a/src/app/api/cron/garmin-sync/route.ts
+++ b/src/app/api/cron/garmin-sync/route.ts
@@ -58,6 +58,32 @@ export async function POST(request: Request) {
 
   const pb = createPocketBaseClient();
 
+  // Authenticate as admin to bypass API rules and list all users
+  const adminEmail = process.env.POCKETBASE_ADMIN_EMAIL;
+  const adminPassword = process.env.POCKETBASE_ADMIN_PASSWORD;
+  if (!adminEmail || !adminPassword) {
+    logger.error("Missing POCKETBASE_ADMIN_EMAIL or POCKETBASE_ADMIN_PASSWORD");
+    return NextResponse.json(
+      { error: "Server misconfiguration" },
+      { status: 500 },
+    );
+  }
+
+  try {
+    await pb
+      .collection("_superusers")
+      .authWithPassword(adminEmail, adminPassword);
+  } catch (authError) {
+    logger.error(
+      { err: authError },
+      "Failed to authenticate as PocketBase admin",
+    );
+    return NextResponse.json(
+      { error: "Database authentication failed" },
+      { status: 500 },
+    );
+  }
+
   // Fetch all users (we'll filter garminConnected in code to avoid PocketBase query syntax issues)
   // Also filter out users without required date fields (garminTokenExpiresAt, lastPeriodDate)
   const allUsers = await pb.collection("users").getFullList<User>();