Rowing uses your legs, back and arms together. Watts measure the power you put into the flywheel, so they reflect your real effort better than stroke rate or time. On a Concept2 rower, you can switch the monitor display to watts.
Technique affects your watts
About 60% of each stroke's power should come from your legs. Beginners often pull mostly with their arms, which tires them out at low watts. Learning to drive with the legs raises your watts at the same effort and gets more work done in the same time.
Total vs net calories
Your body burns calories all day just to keep running, roughly 1 MET. The total figure includes those calories. The net figure subtracts them, leaving only the extra energy the activity cost. Net is the more honest number if you are thinking about how much a workout adds to a calorie deficit.
Don't count the same calories twice
If you set a calorie target with our TDEE calculator and chose an activity level that includes your usual workouts, those workouts are already in your target. Adding exercise calories on top would count them twice. Use these numbers for workouts beyond your normal routine, or to compare activities.
How accurate is this?
MET values are averages measured in groups of adults aged 19 to 59. Your real burn can differ by 10 to 20% or more because of fitness, technique, body composition and how hard you actually worked. Adults over 60 often burn somewhat less than these estimates; a separate Compendium for older adults exists for that reason. Treat the result as a solid estimate rather than an exact count. Fitness trackers are no more precise; see how accurate fitness trackers are for calories.
Questions people ask
How many calories does 20 minutes of rowing burn?
For a 155 lb person at 100 to 149 watts, about 185 calories in total. At 150 to 199 watts it is closer to 270.
Is the rowing machine good for weight loss?
It works most of your major muscles with low impact, so you can train hard without pounding your joints. It supports weight loss the way other cardio does, by adding to a calorie deficit.
What are good rowing watts for a beginner?
Many beginners average somewhere around 70 to 120 watts for a steady session. The number rises quickly as technique improves.
Sources
- Herrmann SD, Willis EA, Ainsworth BE, et al. 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science. 2024;13(1):6–12. pacompendium.com