diff --git a/src/shared/hooks/useTimer.ts b/src/shared/hooks/useTimer.ts
index 4273a6c..c77ae76 100644
--- a/src/shared/hooks/useTimer.ts
+++ b/src/shared/hooks/useTimer.ts
@@ -5,6 +5,7 @@
 
 import { useRef, useEffect, useCallback } from 'react'
 import { usePlayerStore } from '../stores'
+import i18n from '@/src/shared/i18n'
 import type { Workout } from '../types'
 
 export type TimerPhase = 'PREP' | 'WORK' | 'REST' | 'COMPLETE'
@@ -47,7 +48,7 @@ export function useTimer(workout: Workout | null): UseTimerReturn {
     workTime: 20,
     restTime: 10,
     rounds: 8,
-    exercises: [{ name: 'Ready', duration: 20 }],
+    exercises: [{ name: i18n.t('screens:player.phases.prep'), duration: 20 }],
   }
 
   // Calculate phase duration
@@ -75,7 +76,7 @@ export function useTimer(workout: Workout | null): UseTimerReturn {
 
     intervalRef.current = setInterval(() => {
       const s = usePlayerStore.getState()
-      if (s.timeRemaining <= 1) {
+      if (s.timeRemaining <= 0) {
         // Phase transition
         if (s.phase === 'PREP') {
           store.setPhase('WORK')
diff --git a/src/shared/stores/activityStore.ts b/src/shared/stores/activityStore.ts
index 7cf156e..414ba99 100644
--- a/src/shared/stores/activityStore.ts
+++ b/src/shared/stores/activityStore.ts
@@ -87,7 +87,6 @@ export const useActivityStore = create<ActivityState>()(
 // Standalone helper functions (use outside selectors)
 export function getWeeklyActivity(history: WorkoutResult[]): DayActivity[] {
   const days: DayActivity[] = []
-  const dayNames = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat']
   const today = new Date()
   const startOfWeek = new Date(today)
   startOfWeek.setDate(today.getDate() - today.getDay())
@@ -100,7 +99,7 @@ export function getWeeklyActivity(history: WorkoutResult[]): DayActivity[] {
       r => getDateString(r.completedAt) === dateStr
     )
     days.push({
-      date: dayNames[i],
+      date: String(i),
       completed: workoutsOnDay.length > 0,
       workoutCount: workoutsOnDay.length,
     })
diff --git a/src/shared/stores/userStore.ts b/src/shared/stores/userStore.ts
index 090d5c0..6cd1883 100644
--- a/src/shared/stores/userStore.ts
+++ b/src/shared/stores/userStore.ts
@@ -6,7 +6,16 @@
 import { create } from 'zustand'
 import { persist, createJSONStorage } from 'zustand/middleware'
 import AsyncStorage from '@react-native-async-storage/async-storage'
-import type { UserProfile, UserSettings, SubscriptionPlan } from '../types'
+import { getLocales } from 'expo-localization'
+import type { UserProfile, UserSettings, SubscriptionPlan, FitnessLevel, FitnessGoal, WeeklyFrequency } from '../types'
+
+interface OnboardingData {
+  name: string
+  fitnessLevel: FitnessLevel
+  goal: FitnessGoal
+  weeklyFrequency: WeeklyFrequency
+  barriers: string[]
+}
 
 interface UserState {
   profile: UserProfile
@@ -15,16 +24,22 @@ interface UserState {
   updateProfile: (updates: Partial<UserProfile>) => void
   updateSettings: (updates: Partial<UserSettings>) => void
   setSubscription: (plan: SubscriptionPlan) => void
+  completeOnboarding: (data: OnboardingData) => void
 }
 
 export const useUserStore = create<UserState>()(
   persist(
     (set) => ({
       profile: {
-        name: 'Alex',
-        email: 'alex@example.com',
-        joinDate: 'January 2026',
-        subscription: 'premium-monthly',
+        name: '',
+        email: '',
+        joinDate: new Date().toLocaleDateString(getLocales()[0]?.languageTag ?? 'en-US', { month: 'long', year: 'numeric' }),
+        subscription: 'free',
+        onboardingCompleted: false,
+        fitnessLevel: 'beginner',
+        goal: 'cardio',
+        weeklyFrequency: 3,
+        barriers: [],
       },
       settings: {
         haptics: true,
@@ -48,6 +63,19 @@ export const useUserStore = create<UserState>()(
         set((state) => ({
           profile: { ...state.profile, subscription: plan },
         })),
+
+      completeOnboarding: (data) =>
+        set((state) => ({
+          profile: {
+            ...state.profile,
+            name: data.name,
+            fitnessLevel: data.fitnessLevel,
+            goal: data.goal,
+            weeklyFrequency: data.weeklyFrequency,
+            barriers: data.barriers,
+            onboardingCompleted: true,
+          },
+        })),
     }),
     {
       name: 'tabatafit-user',
diff --git a/src/shared/types/user.ts b/src/shared/types/user.ts
index 1ae8f48..90a6a77 100644
--- a/src/shared/types/user.ts
+++ b/src/shared/types/user.ts
@@ -12,11 +12,20 @@ export interface UserSettings {
   reminderTime: string
 }
 
+export type FitnessLevel = 'beginner' | 'intermediate' | 'advanced'
+export type FitnessGoal = 'weight-loss' | 'cardio' | 'strength' | 'wellness'
+export type WeeklyFrequency = 2 | 3 | 5
+
 export interface UserProfile {
   name: string
   email: string
   joinDate: string
   subscription: SubscriptionPlan
+  onboardingCompleted: boolean
+  fitnessLevel: FitnessLevel
+  goal: FitnessGoal
+  weeklyFrequency: WeeklyFrequency
+  barriers: string[]
 }
 
 export interface Achievement {