Simon Lebriac is a French physical trainer whose name has been circulating for several months in the connected sports ecosystem. His approach relies on the exploitation of biometric data collected by wearable sensors to adjust training in almost real-time. The concept is not new, but the method he proposes raises a specific technical question: are the algorithms used to interpret this data reliable in real-world conditions?
Scientific validation of sports wearables: what recent publications say
Connected sports rely on sensors capable of measuring heart rate, heart rate variability, sleep quality, and even continuous blood glucose levels. This data feeds into artificial intelligence models intended to predict fatigue, adjust training loads, and, in some cases, anticipate injuries.
The promise of injury prediction remains scientifically fragile. A meta-analysis commented on by MondoSanità in September 2026 has downplayed the actual ability of connected watches and bracelets to predict muscle or joint injuries. The models show correlations, but their predictive value in real training situations remains limited.
Moreover, a review published by Sportlinea in August 2026 (From Monitoring to Prevention: Wearable Technology for Injury Prevention in Sport) highlighted that AI models are not all sufficiently validated in real conditions. Variability between individuals, measurement biases related to sensor positioning, and differences in protocols from one sport to another make generalizations risky.
It is in this context that Simon Lebriac’s approach makes sense: rather than promising a miracle tool, he emphasizes the intersection of connected data and the human expertise of the coach. As detailed in articles from the Bonjour Sportif website, his method combines algorithmic analysis with traditional individualized monitoring.
Sports health data and European legal framework
One often overlooked aspect in discussions about connected sports concerns the ownership and portability of data. Each training session generates a volume of biometric data that flows between the sensor, a mobile application, and the manufacturer’s servers. The question of who controls this information has become a major regulatory issue.
Since September 12, 2025, the European Data Act (regulation 2023/2854) grants users the right to access data generated by their connected devices and to request its transfer to a company of their choice. For new products launched after September 12, 2026, direct access to data must be provided from the design stage of the device.
This development changes the game for athletes and physical trainers. Specifically, an athlete using a GPS watch from a given brand will be able to demand the transfer of their training history to another platform. This portability strengthens the position of independent coaches like Simon Lebriac, who no longer depend on a closed ecosystem to exploit their athletes’ data.
The GDPR already regulated the collection of health data, but the Data Act adds a specific layer for connected devices. Professional clubs equipped with wearables will need to adapt their internal processes to ensure this transparency.
Connected sports and training: concrete devices used on the field
To understand what Simon Lebriac offers, it is necessary to identify the types of sensors on which his protocol relies. The market for sports wearables has significantly diversified.
- Sports GPS watches (Garmin, Coros, Huawei Watch GT7 Pro) measure optical heart rate, estimated VO2 max, training load, and running metrics such as cadence or vertical oscillation.
- Smart textiles integrate sensors directly into clothing, eliminating the need for a wristband or chest strap, and capture muscular or postural data.
Lebriac’s contribution does not lie in the manufacturing of these tools, but in the protocol for cross-interpreting the data. His method consists of aggregating data streams from multiple sensors to produce a unique dashboard, which is then interpreted by the physical trainer.
Limits of the model: between overinterpretation of data and technological dependence
The main criticism directed at connected sports, and by extension at Lebriac’s method, concerns the risk of overinterpreting incomplete data. An optical heart rate sensor on the wrist does not have the precision of a medical electrocardiogram. Basing training decisions on approximate measurements can lead to inappropriate adjustments.
Another pitfall lies in the psychological dependence on technological feedback. Athletes who no longer train without consulting their watch gradually lose the ability to listen to their own bodily sensations. The subjective feeling of fatigue, refined by years of practice, remains an indicator that algorithms struggle to replace.
- The accuracy of sensors varies depending on the type of sport, wrist morphology, and weather conditions.
- The proprietary algorithms of watch manufacturers are not always documented, making scientific auditing difficult.
- The shift from individual use to a decision-making infrastructure for clubs raises questions of liability in the event of algorithmic interpretation errors.
Simon Lebriac acknowledges these limitations in his public interventions. His response is to position technology as a tool for assistance, not as a substitute for the coach’s judgment. The distinction is subtle, but it sets his approach apart from purely marketing rhetoric about wearables.
Connected sports are neither a completed revolution nor a mere trend. The European regulatory framework is gradually structuring access to data, scientific research tempers commercial promises, and practitioners like Lebriac are trying to build a reasoned use of these technologies. The robustness of this approach will be measured on the ground, season after season, through the concrete results of the athletes who adopt it.
