TRaining IMPulse (TRIMP) is a metric that quantifies the training load of a particular session, taking into account the duration and intensity of the workout. Unlike Training Stress Score (TSS), which can use various intensity metrics such as power or pace, the traditional TRIMP calculation is primarily based on heart rate data. Still, the concept can be adapted to consider other intensity measures.
To better understand how TRIMP works, let’s look at the key factors involved in the calculation:
- Duration: This is the length of your training session, usually measured in minutes.
- Intensity: This is typically a percentage of your maximum capacity (like your maximum heart rate, threshold pace, or threshold power) during the workout.
- Weighting factor: This accounts for the nonlinear relationship between exercise intensity and physiological stress. The higher the intensity, the greater the physiological stress.
The basic formula for TRIMP is as follows:
TRIMP = Duration * Intensity * Weighting Factor
Let’s say you run for 60 minutes at an intensity that is 85% of your maximum capacity, whether that be heart rate, pace, or power. Assuming a weighting factor of 1.5 for illustration purposes (the actual factor varies depending on the method used to calculate TRIMP and personal parameters), the TRIMP for this workout would be:
TRIMP = 60 (Duration) * 0.85 (Intensity) * 1.5 (Weighting Factor) = 76.5
This score quantifies the physiological stress of the workout. By tracking TRIMP across sessions over time, you can monitor the accumulated training load. This helps guide adjustments to your training plan to optimize performance and recovery, and reduce the risk of overtraining.
TRIMP is a relative measure and will be individual to each athlete based on their fitness level and individual physiological parameters. Therefore, it’s crucial to adjust these calculations according to personal data and responses to training.