Hey Minions... what's the difference between Virtual Watts and the measurements from a power meter?
Virtual Watts is an estimated measure of effort you're putting through the pedals/bike/trainer and is a factor of your wheel speed and the power curve of your chosen trainer.
The watts (w) measured by various power meters measure the actual force applied through strategically placed and finely calibrated sensors (known as strain gauges). This force, combined with your cadence, allows for a calculation of power, measured in watts.
The biggest thing to think about when considering the advantages of a power meter vs. Virtual Watts is the cost. Power meters are pricey!
The major advantage of having a power meter installed on your bike is that you can measure your power output while training indoors and while riding and racing outdoors. Virtual Watts are married to your turbo trainer and it can't leave the pain cave. Look at Virtual Watts like a gateway drug (the good kind of drug that transforms your health!). If you get hooked to training with power you might then consider investing in a power meter. If you ride purely for the pleasure of being social and having the sun on your face then investing in a power meter may not be for you. In any case, the upfront cost of training with Virtual Watts is comparatively low and will help you decide!