The medical certificate is the most sensitive administrative document in the registration file for the Diagonale des Fous. Its validity, content, and the timing of its submission alone determine whether a runner will be able to start in October 2026. With the recent addition of a mandatory health questionnaire and the tightening of cardiological recommendations, the medical requirements for this 34th edition are no longer just a simple doctor’s stamp.
Medical certificate and health questionnaire: two distinct documents to provide
The most common confusion among registrants concerns the number of medical documents to submit. Contrary to what many registration pages suggest, the Grand Raid of La Réunion now operates on a mixed model: medical certificate plus health questionnaire. Each document has its own deadline and submission procedure.
The medical certificate must be uploaded first. For the 2025 edition, the deadline was set for August 31. The health questionnaire, on the other hand, had to be completed and submitted online before September 15 at 12 PM, La Réunion time. Without these two validated documents, no registration can be finalized, regardless of the lottery results.
This system is inspired by the French federal regulations, but general information about the Diagonale 2026 often continues to refer to a single certificate. It is essential to monitor the official Grand Raid calendar to avoid missing either of the two deadlines, as the second one (the questionnaire) sometimes falls just a few weeks before the race.
| Document | Content | Submission | Consequence if absent |
|---|---|---|---|
| Medical certificate | Statement “fit for competitive running” | Online, before the deadline (end of August for the 2025 edition) | Registration not validated |
| Health questionnaire | Self-assessment of medical history and risk factors | Online, after the certificate, before the second deadline (mid-September for 2025) | Registration not validated |
Anticipating the medical certificate required for the Diagonale des Fous 2026 as soon as the lottery confirmation is received avoids last-minute rushes to the doctor, especially for runners residing outside La Réunion.
Cardiological assessment before an ultra-trail: recommendation or real obligation
The Grand Raid regulations mention a certificate attesting to the fitness for competitive running. No line formally requires a stress electrocardiogram or a cardiac ultrasound. In practice, the situation is more nuanced.
Several health-oriented sources for athletes and long-distance trail running indicate that organizers now recommend a complete cardiological assessment for runners with risk factors or exceeding a certain age. This recommendation aims to prevent cardiac accidents during efforts lasting several hours, in extreme climatic conditions (heat, humidity, altitude).
However, a general practitioner can legally sign the certificate without prescribing additional tests. The difference between the letter of the regulations and medical reality creates a gray area that each runner must navigate with their practitioner.
- Rest ECG: a basic examination often performed in the office, which detects rhythm abnormalities at rest but not under stress
- Stress ECG (treadmill or bike test): recommended for runners over 40 or with a family history of cardiovascular issues
- Cardiac ultrasound: sometimes suggested as a complement to assess the structure of the heart muscle, especially for regular ultra-endurance practitioners
A certificate signed after a thorough assessment does not guarantee the absence of risk, but it provides a base of data that can be useful in case of problems on the course. The medical staff at the Grand Raid’s aid stations can consult the health questionnaire, which reinforces the importance of declaring any examinations conducted.
Sports prerequisites and medical certificate: the link that no one details
Registration for the Diagonale des Fous 2026 requires two completed races of at least 85 points each in the qualification scale. This threshold filters candidates based on their physical ability to complete an ultra of 180 km and 10,200 m of positive elevation gain.
This sports filter has an indirect effect on the medical aspect. Some doctors, aware of the race’s requirements, rely on the patient’s history of qualifying races to assess their condition. A runner with two recent results in long trails provides a reassuring signal regarding their tolerance for prolonged effort.
Conversely, a candidate whose qualifying races are over a year old, or who has suffered an injury in the meantime, may be directed towards additional examinations before the certificate is issued. The doctor has no regulatory obligation to consult the patient’s race history, but the trend of correlating sports data with medical data is growing in the ultra-trail community.
Typical timeline for a runner drawn in the March 2026 lottery
The lottery for the Diagonale des Fous 2026 takes place on March 18. Between this date and the scheduled start on October 15, the runner has about seven months to complete their medical file. Planning the medical appointment as early as April allows sufficient time to conduct a cardiological assessment if the doctor deems it necessary, and then submit the certificate and questionnaire on time.
Waiting until August exposes one to two risks: the saturation of slots with sports cardiologists (waiting times of several weeks in some regions) and the impossibility of undergoing another examination if the first reveals an anomaly that needs further investigation.
Validity of the medical certificate for the Diagonale des Fous: duration and mandatory mention
The certificate must include the statement “fit for competitive running”. A generic statement like “fit for sports practice” is not sufficient and will be rejected during the administrative check.
The validity period follows French sports regulations, but the Grand Raid organization can set its own calendar constraints. The certificate must cover the date of the race, meaning that a document issued more than a year before the event risks being rejected. A certificate dated March or April 2026 remains acceptable for a race in October.
Submission is done exclusively online, via the “Registrations” section of the official Grand Raid website. No postal submissions are accepted. The digital format (scan or readable photo) must clearly show the date, the fitness statement, the stamp, and the doctor’s signature. A blurry or cropped document will lead to rejection and require restarting the procedure.