GlycoGuard: the second wind, on your wrist
To our knowledge, the first watch app designed for McArdle disease: a second wind timer (6-10 min), a target heart-rate zone and a pre-exercise carb reminder — synced in real time with your MyFit.care journal.
Second wind timer
A dedicated timer for the 6-10 minute adaptation window described in the literature: start gently and watch your progress without pulling out your phone.
Target heart-rate zone
Continuous display of your heart rate against your personal target zone (configurable in MyFit.care), with a discreet signal when you drift above it.
Pre-exercise reminder
A reminder of the published pre-exercise carbohydrate guidance (Vissing & Haller protocol, NEJM 2003), synced with your MyFit.care plan.
How to install it
- Create a free account at app.myfit.care (or try the demo).
- In Settings → GlycoGuard, download the watch app (Connect IQ file).
- Install it on your Connect IQ-compatible Garmin watch (Forerunner, Venu, Fenix, Vivoactive…).
- Pair the watch with the displayed code: each device gets its own key (HMAC-SHA256-signed messages, encrypted in transit, revocable at any time).
Why a watch app for McArdle?
In McArdle disease (glycogen storage disease type V), the first minutes of exercise are the hardest: muscle glycogen cannot be mobilised and energy has to come from elsewhere. After 6 to 10 minutes of gentle activity, most people describe a second wind: exercise suddenly feels much easier. Starting too hard, too fast, is the classic trap — and it is exactly what an at-a-glance wrist display helps avoid.
GlycoGuard keeps the three key published cues visible during exercise: time elapsed in the adaptation window, heart rate against your target zone, and pre-exercise carb intake. The data then lands in your MyFit.care journal, ready to discuss with your care team.
Educational information based on published sources (McArdle review, 2020, Vissing & Haller NEJM 2003, IamGSD) — GlycoGuard is not a substitute for a diagnosis or medical advice. If you experience unusual pain, contractures or dark urine, stop exercising and seek medical care.
Frequently asked questions
Which watches does it run on?
Recent Connect IQ-compatible Garmin watches (Forerunner, Venu, Fenix, Vivoactive…). The file is provided from your MyFit.care account.
Is it free?
Yes, GlycoGuard is included with a MyFit.care account (a Free plan is available).
Is my data protected?
A dedicated device key per watch, HMAC-SHA256-signed messages, TLS encryption in transit, and revocation at any time from your settings.
What if I don't have a Garmin watch?
The MyFit.care web app offers the same second wind timer and the pre-exercise carb calculator, usable from your phone.