What is myTrainingForecast?
myTrainingForecast is a science-based training companion that helps runners prevent overuse injuries. Connect your Strava account, and the app analyzes your training patterns to estimate your injury risk and alert you before you push into dangerous territory.
The app was born from personal experience. After a knee injury in May 2017, creator Cyril discovered that many running injuries could be predicted and prevented by tracking the ratio between recent training load and long-term fitness. This insight, backed by sports science research, became the foundation for myTrainingForecast.
The Problem It Solves
Running injuries are extremely common. Research shows that approximately 50% of runners experience an injury each year that prevents them from running, and about 70-80% of running disorders are due to overuse. The primary cause? Running too much, too soon.
Common overuse injuries include runner's knee, shin splints, stress fractures, plantar fasciitis, IT band syndrome, and Achilles tendonitis. Most of these are preventable with proper training load management.
How It Works: The ACR Method
myTrainingForecast uses the Acute:Chronic Workload Ratio (ACR), a method developed by sports scientists Blanch and Gabbett and used by professional coaches in football, rugby, and cycling.
The formula is simple: divide your 1-week training load (acute) by your 4-week average load (chronic).
The ACR helps identify when you're ramping up training faster than your body can adapt. While your cardiovascular system adapts in days, your connective tissues (tendons, ligaments, bones) need weeks or months. This mismatch is why runners often feel great right before getting injured.
The Four ACR Zones
Green Zone (80-130%): The "sweet spot" where injury risk is lowest. This is where you want to stay for sustainable training.
Orange Zone (130-150%): Caution zone. Injury risk begins increasing noticeably. Consider adding recovery.
Red Zone (150%+): Danger zone. Significantly elevated injury risk. Your training has "spiked" and extra recovery time is needed.
Blue Zone (below 80%): Undertraining zone. Fitness deteriorates here, which can paradoxically increase future injury risk when you resume normal training.
Key Features
Injury Risk Forecasting
After each activity syncs from Strava, myTrainingForecast calculates your current ACR and estimates your overuse injury risk for the next 7 days. You receive email alerts when your risk level changes.
Training Planner
Plan your upcoming runs and see how they'll affect your injury risk before you do them. The planner helps you build mileage progressively while staying in the green zone.
Historical Analysis
Review your training history to understand patterns. If you've been injured before, you can often identify the training spike that preceded it.
Multi-Sport Support (Premium)
Premium users can track runs, rides, and swims together, getting a complete picture of total training stress across all activities.
Air Quality Monitoring (Premium)
Check air quality conditions for your training location, helping you decide when outdoor exercise is advisable.
Who It's For
myTrainingForecast is ideal for:
- Injury-prone runners who want to break the cycle of training, injury, recovery, repeat
- Runners building mileage who need guidance on how fast to increase weekly volume
- Marathon and ultramarathon trainers managing high training loads over extended periods
- Comeback runners returning from injury or time off who need to rebuild safely
- Data-driven athletes who want science-backed insights rather than guesswork
The Science Behind It
The ACR methodology is backed by peer-reviewed research. Studies across multiple sports have found a "U-shaped" relationship between ACR and injury risk, with ratios between 0.80 and 1.30 associated with the lowest injury rates.
Key research includes work by Hulin, Gabbett, Blanch and others showing that training load spikes are strongly associated with increased injury risk, and that athletes with higher chronic workloads are more resistant to injury when ACR stays moderate.
The app uses the methodology from Blanch & Gabbett (2015) to estimate overuse injury likelihood, providing a practical application of professional sports science for recreational runners.
Free vs Premium
The free tier provides the core ACR model with a 1-week planner and 1-month of history. Premium adds personalized injury prediction that factors in pace, elevation, age, and injury history, plus a 12-week planner, 2-year history, and multi-sport tracking. Premium includes a 7-day free trial.
The app is independently developed with no ads, no data selling, and no outside investors.
