diff --git a/App.tsx b/App.tsx
index aed79ae..b022053 100644
--- a/App.tsx
+++ b/App.tsx
@@ -73,12 +73,13 @@ function App() {
     setCurrentUser(updatedUser);
   };
 
-  const handleStartSession = (plan?: WorkoutPlan) => {
+  const handleStartSession = (plan?: WorkoutPlan, startWeight?: number) => {
     if (!currentUser) return;
 
     // Get latest weight from profile or default
     const profile = getCurrentUserProfile(currentUser.id);
-    const currentWeight = profile?.weight || 70;
+    // Use provided startWeight, or profile weight, or default 70
+    const currentWeight = startWeight || profile?.weight || 70;
 
     const newSession: WorkoutSession = {
       id: crypto.randomUUID(),
@@ -155,6 +156,7 @@ function App() {
           {currentTab === 'TRACK' && (
             <Tracker
               userId={currentUser.id}
+              userWeight={currentUser.profile?.weight}
               activeSession={activeSession}
               activePlan={activePlan}
               onSessionStart={handleStartSession}
diff --git a/components/Tracker.tsx b/components/Tracker.tsx
index 9066b5d..37b6194 100644
--- a/components/Tracker.tsx
+++ b/components/Tracker.tsx
@@ -8,16 +8,17 @@ import { t } from '../services/i18n';
 
 interface TrackerProps {
     userId: string;
+    userWeight?: number;
     activeSession: WorkoutSession | null;
     activePlan: WorkoutPlan | null;
-    onSessionStart: (plan?: WorkoutPlan) => void;
+    onSessionStart: (plan?: WorkoutPlan, startWeight?: number) => void;
     onSessionEnd: () => void;
     onSetAdded: (set: WorkoutSet) => void;
     onRemoveSet: (setId: string) => void;
     lang: Language;
 }
 
-const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, onSessionStart, onSessionEnd, onSetAdded, onRemoveSet, lang }) => {
+const Tracker: React.FC<TrackerProps> = ({ userId, userWeight, activeSession, activePlan, onSessionStart, onSessionEnd, onSetAdded, onRemoveSet, lang }) => {
     const [exercises, setExercises] = useState<ExerciseDef[]>([]);
     const [plans, setPlans] = useState<WorkoutPlan[]>([]);
     const [selectedExercise, setSelectedExercise] = useState<ExerciseDef | null>(null);
@@ -35,7 +36,7 @@ const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, on
     const [bwPercentage, setBwPercentage] = useState<string>('100');
 
     // User Weight State
-    const [userBodyWeight, setUserBodyWeight] = useState<string>('70');
+    const [userBodyWeight, setUserBodyWeight] = useState<string>(userWeight ? userWeight.toString() : '70');
 
     // Create Exercise State
     const [isCreating, setIsCreating] = useState(false);
@@ -57,17 +58,12 @@ const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, on
 
             if (activeSession?.userBodyWeight) {
                 setUserBodyWeight(activeSession.userBodyWeight.toString());
-            } else {
-                // Profile fetch needs to be async too if we updated it, 
-                // but for now let's assume we can get it or it's passed.
-                // Actually getCurrentUserProfile returns undefined now.
-                // We should probably fetch it properly.
-                // For now, default to 70.
-                setUserBodyWeight('70');
+            } else if (userWeight) {
+                setUserBodyWeight(userWeight.toString());
             }
         };
         loadData();
-    }, [activeSession, userId]);
+    }, [activeSession, userId, userWeight]);
 
     // Timer Logic
     useEffect(() => {
@@ -128,7 +124,7 @@ const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, on
         if (plan && plan.description) {
             setShowPlanPrep(plan);
         } else {
-            onSessionStart(plan);
+            onSessionStart(plan, parseFloat(userBodyWeight));
         }
     };
 
@@ -358,10 +354,10 @@ const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, on
                                     key={step.id}
                                     onClick={() => jumpToStep(idx)}
                                     className={`w-full text-left px-4 py-3 rounded-full text-sm flex items-center justify-between transition-colors ${idx === currentStepIndex
-                                            ? 'bg-primary-container text-on-primary-container font-medium'
-                                            : idx < currentStepIndex
-                                                ? 'text-on-surface-variant opacity-50'
-                                                : 'text-on-surface hover:bg-white/5'
+                                        ? 'bg-primary-container text-on-primary-container font-medium'
+                                        : idx < currentStepIndex
+                                            ? 'text-on-surface-variant opacity-50'
+                                            : 'text-on-surface hover:bg-white/5'
                                         }`}
                                 >
                                     <span>{idx + 1}. {step.exerciseName}</span>
@@ -556,8 +552,8 @@ const Tracker: React.FC<TrackerProps> = ({ userId, activeSession, activePlan, on
                                             key={type.id}
                                             onClick={() => setNewType(type.id)}
                                             className={`px-4 py-2 rounded-lg flex items-center gap-2 text-xs font-medium border transition-all ${newType === type.id
-                                                    ? 'bg-secondary-container text-on-secondary-container border-transparent'
-                                                    : 'bg-transparent text-on-surface-variant border-outline hover:border-on-surface-variant'
+                                                ? 'bg-secondary-container text-on-secondary-container border-transparent'
+                                                : 'bg-transparent text-on-surface-variant border-outline hover:border-on-surface-variant'
                                                 }`}
                                         >
                                             <type.icon size={14} /> {type.label}
diff --git a/server/prisma/dev.db b/server/prisma/dev.db
index bfbc96e..7037aa4 100644
Binary files a/server/prisma/dev.db and b/server/prisma/dev.db differ
diff --git a/server/src/routes/sessions.ts b/server/src/routes/sessions.ts
index 9e8f94f..8e7e023 100644
--- a/server/src/routes/sessions.ts
+++ b/server/src/routes/sessions.ts
@@ -42,6 +42,11 @@ router.post('/', async (req: any, res) => {
         const userId = req.user.userId;
         const { id, startTime, endTime, userBodyWeight, note, sets } = req.body;
 
+        // Convert timestamps to Date objects if they are numbers
+        const start = new Date(startTime);
+        const end = endTime ? new Date(endTime) : null;
+        const weight = userBodyWeight ? parseFloat(userBodyWeight) : null;
+
         // Check if session exists
         const existing = await prisma.workoutSession.findUnique({ where: { id } });
 
@@ -53,9 +58,9 @@ router.post('/', async (req: any, res) => {
             const updated = await prisma.workoutSession.update({
                 where: { id },
                 data: {
-                    startTime,
-                    endTime,
-                    userBodyWeight,
+                    startTime: start,
+                    endTime: end,
+                    userBodyWeight: weight,
                     note,
                     sets: {
                         create: sets.map((s: any, idx: number) => ({
@@ -65,7 +70,7 @@ router.post('/', async (req: any, res) => {
                             reps: s.reps,
                             distanceMeters: s.distanceMeters,
                             durationSeconds: s.durationSeconds,
-                            completed: s.completed
+                            completed: s.completed !== undefined ? s.completed : true
                         }))
                     }
                 },
@@ -78,9 +83,9 @@ router.post('/', async (req: any, res) => {
                 data: {
                     id, // Use provided ID or let DB gen? Frontend usually generates UUIDs.
                     userId,
-                    startTime,
-                    endTime,
-                    userBodyWeight,
+                    startTime: start,
+                    endTime: end,
+                    userBodyWeight: weight,
                     note,
                     sets: {
                         create: sets.map((s: any, idx: number) => ({
@@ -90,7 +95,7 @@ router.post('/', async (req: any, res) => {
                             reps: s.reps,
                             distanceMeters: s.distanceMeters,
                             durationSeconds: s.durationSeconds,
-                            completed: s.completed
+                            completed: s.completed !== undefined ? s.completed : true
                         }))
                     }
                 },