Rowing Power Calculator Formula
Understand the math behind the rowing power calculator. Each variable explained with a worked example.
Formulas Used
Power Output
watts = round(2.8 / pow(pace_per_m, 3))Watts per kg
watts_per_kg = round(2.8 / pow(pace_per_m, 3) / body_weight_kg * 100) / 100Calories per Hour (est)
cal_per_hour = round((2.8 / pow(pace_per_m, 3) + 300) * 0.86 * 4)Variables
| Variable | Description | Default |
|---|---|---|
split_min | Split per 500m (min)(min) | 1 |
split_sec | Split per 500m (sec)(sec) | 55 |
body_weight_lbs | Body Weight(lbs) | 180 |
total_split_sec | Derived value= split_min * 60 + split_sec | calculated |
pace_per_m | Derived value= total_split_sec / 500 | calculated |
body_weight_kg | Derived value= body_weight_lbs * 0.4536 | calculated |
How It Works
How Rowing Power Is Calculated
The Concept2 Formula
Watts = 2.80 / pace^3
Where pace = split time in seconds / 500 (seconds per meter).
Power-to-Weight
Watts per kilogram (W/kg) is a useful metric for comparing rowers of different sizes. Lightweight rowers may produce fewer absolute watts but can be very competitive on a W/kg basis.
Benchmarks
Worked Example
Calculate watts for a 1:55 per 500m split at 180 lbs body weight.
- 01Split in seconds = 1 x 60 + 55 = 115 seconds per 500m.
- 02Pace per meter = 115 / 500 = 0.23 sec/m.
- 03Watts = 2.80 / (0.23)^3 = 2.80 / 0.01217 = 230 W.
- 04Body weight = 180 x 0.4536 = 81.6 kg.
- 05Watts/kg = 230 / 81.6 = 2.82 W/kg.
Frequently Asked Questions
Why is the relationship between split and watts cubic?
Drag force in rowing increases with the cube of velocity. To go 10% faster, you need about 33% more power. This is why shaving seconds off a fast split is exponentially harder than improving a slow split.
What is a good watts per kg for rowing?
Recreational: 1.5-2.5 W/kg. Club competitive: 2.5-3.5 W/kg. Collegiate: 3.5-4.5 W/kg. Elite: 4.5+ W/kg. Lightweight rowers at 2.8+ W/kg are quite competitive.
Does the Concept2 monitor show actual watts?
Yes, the PM5 monitor displays watts in real time. It calculates watts from the flywheel deceleration between strokes. The formula is the same one used in this calculator.
Ready to run the numbers?
Open Rowing Power Calculator