The dictionary definition is “a unit of power equal to the work done at the rate of one joule per second,” and it also applies to the fitness world.
In relation to a treadmill, it is the power you push out when applying energy to overcome a resistance like matching speeds of the belt under your feet.
I’ll try not to get too sciency on you, but here are the basics of what watts and your run on the treadmill tell you about your workout.\
One Type of Power to Measure Progress
Everything we do is measured, including how much power we exert during a workout session. That power is calculated by many formulas. One of them is Power = Work/Time. Another way includes using watts to determine how many calories you burn.
Energy burned (calories) = AV Power (watts) X Duration X 3.6, with the average fit person producing approximately 3 watts per kg. For us in the US, 100 lbs = 45.4 kilograms.
Watts measures the amount of energy you put into the workout, not what you get out of it. You would measure results by calories burned, distance run, or time in a workout session.
The force you put into your movements is how many watts you create. This can be done by using the formula P=W/T. Once you establish your watt base, you can use the treadmill to push your power to the max. So, the harder you push against the belt, the more power you produce.
Other measures of progress include testing your VO2 max while running, METs, RHR, and calories burned vs. consumed.
VO2 Max Vs. Watts
Determining your VO2 max tells you how much volume (V) your lungs can obtain during rapid breathing sessions and how much oxygen (O2) you expel to keep yourself moving. This measures your progress in terms of how much energy you can push out or use.
Determining your watt output is measuring how much power you put into your workout to be able to breathe and create more and more energy.
METs Vs. Watts
Measuring with the MET formula means you are trying to determine the expenditure of energy your body is using during that particular activity, whereas watts measure the power you have to push to create energy to keep moving.
METs, or the metabolic equivalent of a task, are also used in relation to how many calories you burn by expending that certain amount of energy.
Where you can calculate METS when sitting here reading this article, you can’t calculate watts used as there isn’t any force being used to produce energy.
Who Benefits the Most from Measuring Watts in a Workout?
Everyone who works out wants to see results and be able to measure those results to show progress. If we don’t see improvement, we get discouraged and quit trying to make changes to the health and wellness of our lives.
Watts is a measurement typically used by serious athletes training for an event like a cross-country run, a triathlon, or maybe a long-distance rowing competition. These athletes need to know precisely how much force or power is required to gain the upper hand in a competition.
The average fitness-loving workout freak (flying my freak flag proudly) is more apt to measure progress with calories burned or how tough the workout is (VO2 max).
How do We Generate Watts During a Workout?
Well, that depends on a few factors. We know the average person with a fitness lifestyle can generate about 3 watts per kg. We also know that resistance creates the need for more power.
So, someone with more body fat will create more wattage power than someone with more muscle than fat. Let’s consider the following scenario.
I weigh 145 lbs or 66 kg, and I’m an average fitness female- That means I am already generating 198 watts constantly.
If you weigh 190 lbs or 86 kg and are an average fitness person, you are generating 258 watts.
Now put us both on a treadmill going the same speed with the same incline, and who puts out the most power? Well, you are heavier, so you need to create more energy to move your body, whereas I am lighter, so not as much force is needed to propel me on the belt.
Notice how it didn’t even come up with who will get there faster? When measuring a watt outage on a treadmill, it’s a matter of power generation. I will most likely win if we are racing to a predetermined distance because I have less weight to move, but you will generate more power, thus winning in a wattage war.
Using Watts as a Training Metric
Treadmills are typically used for cardio and building endurance, so most people track VO2, heart rate, and energy being used during a workout. Some trainers will apply the watt usage parameters to help their clients see a different side of progression. Power and being able to exert more and more is a big mental challenge as well as a physical one.
Calculating your watts on the treadmill session gives you a whole new perspective on what your body can create.
If you have one, you and your trainer can use the calculations above to determine the power you put out, or watts, and keep track of your numbers as a metric to mark ongoing progress.
By measuring the watts as a metric, you can look back and know where you need to increase your power to progress your fitness levels.
Many trainers will compare generating watts on a treadmill to lifting heavier weights in the strength training section of the gym.
To wrap up what watts mean on a treadmill, it is the power your body needs to produce in order to overcome gravity and inertia to propel yourself forward and complete your workout.
The harder you work, the more power (watts) you produce, and the more power you produce, the more you can improve your fitness progression.