When it comes to training effectively and efficiently, it’s hard to deny the advantages a power meter gives you. They allow you to accurately and precisely measure you fitness, no matter what conditions you’re cycling in.
What is power?
Simply stated Power is the amount of force (or work) produced over a certain duration of time. A power meter, such as the PowerTap Hub, takes the torque produced by your pedalling and multiplies it by your speed. Power = Torque x Cadence
Related: Buyers guide to power meters
What are the advantages of training with a power meter?
Most training systems only allow you to measure your body’s response to the work it’s doing. The actual amount of work you perform can vary depending on the conditions your are riding in – temperature, weather and road surface all play a part. This means determining the actual amount of work you perform remains a mystery – or at best an estimate.
Why is this a problem? Doing too much work can lead to overtraining and a risk of injury. Too little, and you’re not maximising the benefits of your output. Using a power meter means you can get an accurate representation of your power output, and use this to ensure you training effectively.
Power meters give you a constant measure of power, and can help you:
- Establish your baseline fitness
- Accurately measure fitness gains, large and small
- Quantify intensity, duration and frequency, rather than estimating
- Prevent overtraining
- Accurately measure energy use for nutritional planning
- Pace properly for time trials or set yourself up for a successful run
Related: Picking the best power meter
How accurate are PowerTap power meters?
The PowerTap is one of only two power meter companies that have had their products researched and third-party validated by Allen Lim and researchers at the University of Boulder, Colorado. They’ve tested the reliability of the hub and found it to be +/- 1.5% accurate. The corresponding PowerTap pedal and chaining power meters were also tested and compared using a PowerTab hub, and have shown the same degree of accuracy.
ANT+ and Bluetooth SMART Technology
PowerTap Power Meters employ both ANT+ and Bluetooth SMART (AKA Bluetooth Low Energy, Bluetooth 4.0 or simply BLE).
ANT+ is a 2.4 GHz wireless network that's used to send information wirelessly from one device to another. It enables two different wireless devices to understand one another, even if the devices are from two different manufacturers. With power meters, this communication can be between the meter itself, speed and cadence sensors, and heart rate monitors.
Bluetooth SMART is a low energy wireless technology. It allows devises with this function to connect wirelessly with applications via your smart phone or tablet devices.
How to calibrate PowerTap Power Meters
Every PowerTap power meter is built and calibrated at the company headquarters in Madison, Wisconsin. However you can also calibrate your power meter from home using a Joule GPS cycling computer. PowerTap has provided a video to guide you though the process.
What is PowerTap?
Based in the United States, PowerTap is one of the best established power meters companies out there with, 16 years of experience in product research and development. The firm has a wide selection of power meter products, from wheel hubs to chain rings, and options to suit many budgets including new soon-to-be-released items designed to help you train effectively with power.
Firstly, the new PowerCal Heart Rate Strap. PowerTap said: “The new PowerCal Heart Rate Strap can get you training with power for as little as £90. It pairs up with your favourite ANT+ bike computer that can read power signals, such as the PowerTap Joule GPS, Garmin 500 and up, Bryton Rider 60, and so on. The PowerCal will show you data based on the stress on your body, looking at minute changes in heart rate responses, not just the peaks as measured in your normal heart rate monitor. The PowerCal also makes a great bridge product for regular power meter users.”
PowerTap also produces the G3 Hub system, which its claims is the simplest power meter on the market. The company said: “Simply add a cassette and your favourite tyres and tube combo and you’re set. It’s also easy to move between bikes, and pairs with your favourite ANT+ device.” Prices start at £699 for a complete wheel, and £599 for hub only.
Brand new this summer are the P1 double-sided power meter system (£999) and C1 chain ring system (£579).
“The P1 system features accurate simplicity at the heart of the operation. The single piece design eliminates ‘plug-in’ accessories. There are no external pods, no installation angle or calibration necessary – you install it, mount the pedals, clip in and go.” This system is powered by easy-to-find AAA batteries.
The new C1 system is designed to adapt to your existing crankset, giving “dual sided power meter accuracy for single sided price”.