Exercise Intensity Calculator Formula
Understand the math behind the exercise intensity calculator. Each variable explained with a worked example.
Formulas Used
Percentage of Max HR
pct_max_hr = exercise_hr / max_hr * 100Percentage of HR Reserve
pct_hrr = (exercise_hr - resting_hr) / hrr * 100Max HR Value
intensity_label = max_hrVariables
| Variable | Description | Default |
|---|---|---|
age | Age(years) | 30 |
resting_hr | Resting Heart Rate(bpm) | 60 |
exercise_hr | Exercise Heart Rate(bpm) | 150 |
max_hr | Derived value= 220 - age | calculated |
hrr | Derived value= max_hr - resting_hr | calculated |
How It Works
Exercise Intensity Metrics
Percentage of Max HR
%MaxHR = Exercise HR / (220 - Age) x 100
Percentage of HR Reserve (Karvonen)
%HRR = (Exercise HR - Resting HR) / (Max HR - Resting HR) x 100
Intensity Levels
| %MaxHR | %HRR | Level | |---|---|---| | <57% | <30% | Very light | | 57-63% | 30-39% | Light | | 64-76% | 40-59% | Moderate | | 77-95% | 60-89% | Vigorous | | >95% | >89% | Near maximal |
Worked Example
A 30-year-old with resting HR 60, exercising at 150 bpm.
age = 30resting_hr = 60exercise_hr = 150
- 01Max HR = 220 - 30 = 190
- 02%MaxHR = 150 / 190 x 100 = 78.9% (Vigorous)
- 03%HRR = (150 - 60) / (190 - 60) x 100 = 69.2% (Vigorous)
Ready to run the numbers?
Open Exercise Intensity Calculator