BANISTER

Banister impulse-response model for monitoring training load, fitness, and fatigue over time.

Protocol for Using Banister's TRIMP in Physical Preparation

1. Objective

• Measure the internal load (physiological response) to training.
• Precisely quantify the effect of stress on the athlete.
• Manage training progression and avoid overtraining.

2. Required Equipment

Heart rate strap or reliable watch to measure heart rate.

Knowledge of:

• Resting heart rate (HRrest).
• Maximal heart rate (HRmax).

3. Banister's TRIMP Formula

TRIMP = Duration (in minutes) × ΔHR × Intensity factor

With:

ΔHR = (HRavg - HRrest) / (HRmax - HRrest)

• HRavg = Average heart rate during the session.
• Intensity factor = Weighting for the effect of intensity:
  • Men: factor ≈ 0.64 × e^(1.92 × ΔHR)
  • Women: factor ≈ 0.86 × e^(1.67 × ΔHR)

(e is the exponential constant ≈ 2.71828)

✅ The exponential factor means that the higher the intensity, the faster the TRIMP load increases.

4. Calculation steps

1. Measure HRrest and HRmax for each athlete.
2. During each session:
   • Record HRavg.
   • Note the total duration in minutes.
3. Calculate ΔHR.
4. Apply the formula to obtain the TRIMP.

5. Daily and weekly tracking

• After each session: Calculate the TRIMP.
• At the end of the week: Sum all daily TRIMPs ➔ Weekly TRIMP.
• Compare week by week to evaluate:
  • Training load.
  • Fatigue level.
  • Need for adaptation (increase or decrease intensity/volume).

6. Practical use of Banister's TRIMP

• Development phase (preparation) ➔ High TRIMP, progressive loads.
• Stabilization phase ➔ Moderate and controlled TRIMP.
• Recovery phase ➔ Low TRIMP, favor recovery.

Warning: TRIMP scores that are too high for too long ➔ fatigue accumulation ➔ injuries or stagnation.

7. Examples

Example of a session:

• HRrest: 60 bpm
• HRmax: 190 bpm
• HRavg for the session: 150 bpm
• Session duration: 60 minutes

➔ Calculation of ΔHR:

ΔHR = (150 - 60) / (190 - 60) = 90 / 130 ≈ 0.69

➔ Calculation of the factor for a man:

Factor = 0.64 × e^(1.92 × 0.69) = 0.64 × e^(1.3248) ≈ 0.64 × 3.76 ≈ 2.4

➔ TRIMP:

TRIMP = 60 × 0.69 × 2.4 ≈ 99.4

So TRIMP ≈ 99 points for this session!

✅ Quick Summary

Step	Action
1	Measure HRrest and HRmax.
2	Record average HR and session duration.
3	Calculate ΔHR.
4	Calculate the intensity factor.
5	Calculate total TRIMP.
6	Track daily and adjust loads.