Support
Questions, bug reports and data requests: open a support ticket (a free GitHub account is needed to post; anyone can read). Typical response time is within two business days. Please include your iPhone model, iOS version and the PeakFuel version shown at the bottom of the You tab.
Getting the app
PeakFuel is an iPhone app for iOS 17 and later: PeakFuel: Athlete Nutrition on the App Store. The download is free; PeakFuel Pro starts with a 7-day free trial.
Subscriptions and purchases
How do I cancel or change my plan?
Open Settings › Apple Account › Subscriptions on your iPhone, or go to apps.apple.com/account/subscriptions. Cancelling at least 24 hours before the trial or period ends means no further charge. Pro stays active until the end of the paid period.
I paid but the app still shows the paywall.
Make sure the iPhone is signed in to the same Apple Account that made the purchase, then tap Restore purchases on the paywall or under You › PeakFuel Pro. Purchases follow your Apple Account, so a new phone signed in to the same account unlocks automatically.
Can I get a refund?
Refunds are handled by Apple. Request one at reportaproblem.apple.com.
Do you offer family sharing?
Not at the moment. Each Apple Account needs its own subscription.
Wearables and training data
My Whoop, Garmin or Apple Watch workouts are not showing up.
PeakFuel reads workouts from Apple Health. First check that your wearable's app is writing workouts to Health (Health app › Profile › Apps › your wearable › Workouts on). Then in PeakFuel go to You › Wearables & apps and make sure Apple Health is connected with background sync on. Opening PeakFuel pulls in anything new; the in-app guide walks through each brand.
Zwift, TrainerRoad or a power meter.
Send those rides to Apple Health (Zwift Companion, TrainerRoad and Wahoo all can), or connect Intervals.icu with your API key. When the same ride arrives from a wrist device and a power source, PeakFuel keeps the power-based energy.
Strava.
Strava sign-in appears under You › Wearables & apps when it is available in your build. Strava's API terms limit how many athletes an app may connect; if the button is missing, use Apple Health or Intervals.icu, which carry the same rides.
A session got cancelled or rained out.
Cancel it on the Train tab. Today's targets and the meal plan update immediately, and anything you already logged stays attached to the nearest meal.
Targets and plans
Why did today's target change?
Targets follow the day's training load, your weight trend, HRV readiness and the days around a competition. Tap the i on the Today screen to see every component and the evidence behind it.
The numbers look higher than my watch.
Wrist devices often underestimate rest-day expenditure and hard sessions. PeakFuel starts from published models and refits your personal baseline from your own intake and weight logs after a few weeks. Log honestly and it converges on you.
Can I use my own foods and meals?
Yes. Add foods by search or barcode, build meals, save any meal as a routine that fills the plan automatically, or choose foods and let PeakFuel size the portions to the meal's targets.
Where the numbers come from
Every target and recommendation is built from peer-reviewed sports-nutrition research and consensus statements. The full, linked reference list is on the Sources page and inside the app under You › Science & sources; each recommendation screen links to its sources.
Your data
Export, back up or delete.
You › Your data lets you export a complete JSON backup, restore it on another device, export research CSVs, or erase everything. Deleting the app deletes its data. There are no accounts and no servers, so there is nothing else to delete on our side. Read the privacy policy.
Apple Health permissions.
Change them any time in the Health app › Profile › Apps › PeakFuel. Health data is used only on your device to compute targets and is never sent anywhere.