What is a power meter and does your bike need it?
If it’s time to take your fitness to the next level, a power meter could be on your radar. By measuring a rider’s power in watts, a power meter can provide instant and valuable training data.
Here’s a look at the basics of the power meter, a look at the most popular models available, and a look at which riders would benefit the most from this cool gear.
What is a wattmeter?
Available to cyclists for over 30 years, a power meter measures a cyclist’s power in watts. This is convenient because it provides precise and real-time data on your journey. Other common measurements, such as speed or heart rate, are not as stable. Weather, hilly roads, and even your daily caffeine intake affect these metrics.
Power, however, provides instant and objective data. This makes it easier to track your progress as a rider over time.
So what do these numbers mean? This equation determines the power:
Instantaneous power = force × angular velocity
In terms of cycling, To obligate is also known as couple, or how hard you press the pedals. Angular velocity, known as cadence, measure how fast you turn these pedals; these are also the bike’s revolutions per minute, or RPMs. Power meters multiply your torque by cadence to determine your power output. Essentially, hit harder and spin faster to increase your wattage.
Modern power meters tend to be small, almost weightless devices that attach to the pedals or crank of a bicycle. Most current models connect wirelessly via Bluetooth 4.0 / Smart or ANT +.
For basic meters, prices range from a few hundred to a few thousand dollars. Cheaper models are on the horizon. But for most riders, a power meter is still a serious investment in buying bikes.
The different types of wattmeter
Some of the more popular types of speedometers attach to the pedals, cranks, or bottom bracket of your bike. The best power meter for you will depend on your driving habits, your budget, and your desire for data accuracy.
Pedal-based power sensors work by measuring the force the rider creates through the pedals. Single-pedal power meters first calculate the power generated by a leg. Then they double this measurement to get the total power of the rider. In addition, unilateral power meters such as the Garmin 3S are easy to install because you simply turn off the pedals.
This makes it easier to use the computer on multiple bikes. Plus, they tend to be priced lower than many other types of meters.
For riders who value greater accuracy in their data, dual-pedal power meters calculate the output of each leg independently. This gives you the data you need to calculate pedaling efficiency and find the differences between the legs in terms of power output. In addition, equipment such as EXAKT double power meter can help measure the overall effectiveness of your relationship.
In general, these advanced devices are more expensive than their single-pedal counterparts.
Then the bottom bracket is another location on the bike for the meters. Some are located in the crank arm, or the part that connects to the pedals. For example, the Step power meter Attaches to your existing crank, making it one of the most affordable power meter options available.
Like single-sided pedal meters, single-crank power meters tend to measure the output of one leg, unless you include an additional sensor.
Meanwhile, devices such as the SRAM AXS Power Meter Spider are built into the crank spider or part of the crank that attaches to the chain. Most spiders have between 3 and 5 arms. Spider meters can usually calculate the power output of the left and right legs by measuring the force applied on a strain gauge.
On a bicycle, the bottom bracket refers to the spindle and the bearings that are between the cranks. It fixes the crankset to the frame of the bicycle. This crucial part of the bike can also house a power meter.
In addition, the power sensors of the bottom bracket such as the PM812 can measure the variations in power of both legs. It also puts the power meter in a rather sheltered spot on the bike, which is ideal for cyclocross or mountain bikers who tackle difficult terrain.
Several other types of power meters are available, including models that connect to your handlebars or hub, but these tend to be less common.
Do you need a power meter for indoor cycling?
If indoor driving is more your speed, note that some devices such as the Kickr smart trainer and StagesBike SB20 smart bike already provide power data for workouts. In these cases, the purchase of a separate power meter is not necessary.
For this type of workout, using an interactive cycling app like Zwift or TrainerRoad can gamify the entire workout experience, encouraging you to crank up the watts like never before.
Who needs a power meter?
For casual riders, power meters are probably not at the top of your bike gear wish list. A bike computer that measures speed, distance, and GPS position may be more useful. In fact, there are plenty of cycling apps available that provide all the data you need, and it’s easy to use your phone as a cycling computer. It is not necessary to buy a new device.
But if you’re looking to keep up with your local cycling club’s group rides, race, or beat the competition in your virtual cycling app, the power meter data can be invaluable. Cyclists interested in road bikes, mountain bikes, cyclocross, triathlon and many other two-wheeled sports can also benefit from the data offered by a power meter.
Finally, people who enjoy calculating numbers for the benefit of their fitness will appreciate the wealth of data these devices offer.
Boost your bike
Once a technology only for the pros, power meters are now more available and affordable to the average rider. With instant and accurate power measurements, these devices turn your bike into a data machine.
For the most part, any rider looking to seriously improve their fitness on the bike will benefit from these devices – the health metrics provided by a power meter are unmatched.
Don’t neglect your bike when it comes to fitness technology and safety. Here are some essential gadgets for cyclists and cyclists.
About the Author