Terms of Use

1. What Derny is

Derny is a training tool for cyclists. It reads data you choose to connect (such as Apple Health, Strava, Garmin, Polar, rides you record in the app and information you enter) and produces suggestions: readiness estimates, training plans, workout targets, ride cues, statistics and equipment reminders.

These suggestions are generated automatically by mathematical rules, general training models and statistics, and in some cases by text summaries written by artificial intelligence running on your device. No physical education professional, coach or doctor reviews them, and they are not personalised to your medical history.

2. Not professional or medical advice

Derny does not replace a physical education professional (in Brazil, one registered with the CREF/CONFEF system under Law 9,696/1998), a qualified coach, a physician or any other health professional. Nothing in Derny is a diagnosis, a prescription or medical advice.

Before starting a training programme, increasing your training or returning after illness, injury or pregnancy, get a medical evaluation, including a cardiological check where appropriate. This is especially important if you have, or suspect, any heart, respiratory, metabolic or musculoskeletal condition, or take medication that affects heart rate.

Stop exercising immediately and seek medical help if you feel chest pain, shortness of breath beyond the expected, dizziness, fainting, palpitations or any unusual symptom. Never ignore your body or professional advice because of a number, score or plan shown by Derny.

3. Your responsibility and the risks of cycling

Cycling and physical training carry inherent risks, including falls, collisions, injury, overtraining and, in rare cases, serious health events or death. You decide whether, how and when to train, and you take part voluntarily and at your own risk.

You are responsible for your safety: following traffic laws, wearing a helmet and appropriate equipment, keeping your bicycle in safe condition, choosing safe routes and conditions, and not looking at or handling your phone or watch in ways that distract you while riding.

Maintenance reminders are estimates based on distance and time. They do not replace inspection by a qualified mechanic, and a component may fail before or after the suggested interval.

4. Accuracy of data and estimates

Values such as heart-rate zones, FTP, training load, readiness, sleep, distance and calories are estimates. They depend on data from sensors and third-party services that may be incomplete, delayed or wrong, and on models that do not fit every person. Derny does not guarantee that any value, plan or result is accurate, complete or suitable for you.

5. Limitation of liability

To the maximum extent permitted by applicable law, Derny and its developer are not liable for injuries, health problems, accidents, damage to equipment or property, or any direct or indirect loss arising from the use of, or reliance on, the app, its suggestions or this website.

Nothing in these terms excludes rights that cannot be waived under the law that applies to you, including the Brazilian Consumer Defence Code (Law 8,078/1990).

6. Beta

Derny is in beta, distributed free of charge through Apple TestFlight. It is provided as is and may contain errors, change, lose features or stop at any time. Keep your own copies of important data; your source services (Apple Health, Strava, Garmin, Polar) keep theirs.

7. Third-party services

Connections to Apple Health, Strava, Garmin, Polar, Zwift, MyWhoosh and others are made only when you authorise them, and those services are governed by their own terms and privacy policies. Derny is not affiliated with, endorsed by or sponsored by any of them. All trademarks belong to their owners.

8. Acceptable use

Do not use Derny for unlawful purposes, try to access other people's data, interfere with the service, or reverse engineer it except where the law allows. Derny is intended for people aged 18 or over; minors may only use it with the consent and supervision of a parent or guardian.

9. Intellectual property

The app, its name, brand, design and content belong to their developer. Your training data remains yours.

10. Changes

These terms may be updated. Significant changes will be shown in the app, and continuing to use Derny after that means you accept the new version.

11. Law and jurisdiction

These terms are governed by the laws of the Federative Republic of Brazil. Disputes will be settled in the courts of the consumer's domicile, as provided by the Consumer Defence Code.

12. Contact

Questions about these terms: through the form on this site.