The power metre: a relatively new tool that only made its way into professional cycling a few years ago. Some swear by it, some only use it during training, and other professional teams adjust their whole tactics to suit each rider’s power data. Although not vital to the average touring cyclist, there are more and more fanatical amateurs and semi-pros who have also taken an interest in them. The metres have been a long time in development, so what do they actually do? and what will the future product be capable of? Let’s dive into the (r)evolution of the power metre.

1986: the beginning

You may be surprised to learn that the first prototype of the power metre dates back to 1986. The German medical engineer Ulrich Schoberer spent years thinking about the needs of the cycling peloton. At the time, a rider’s power output could only be measured in intermittent lab tests; Schoberer, however, thought that power data would be more valuable if collected under real conditions: i.e. from the bike pedals, on the road, during a race. He founded SRM (Schoberer Rad Messtechnik) in 1986, and filed the first patent application for power metre attached to the spider (the spider is the multi-armed piece of a bicycle’s chainset that connects the crank to the chainring(s)).

1988: “training with power”

Although the first step towards measuring power output was created in ’86, it still wasn’t possible to record data. It took another two years before the first SRM Training System became a reality. Thanks to an accompanying computer it became possible to get record data whilst cycling about how much power a riders legs were producing, in watts. This new method of training was dubbed “training with power”.

In 1991, the German national team was the first to use the SRM system during its training camp.

1991: Greg LeMond

Legend Greg LeMond was one of the first top riders to start training with a power metre. The American, and three-time winner of the Tour de France, was quickly convinced by the gadget’s usefulness. In fact, he stated he would have won even more races if he could have obtained the SRM system for training sooner than he did.

2004: Live data on TV

SRM made significant steps with its product development between 1991 and 2004. For example, the compatibility with various groupsets has been expanded (a groupset refers to the organised collection of mechanical bike parts produced by a particular manufacturer). This made it easier for the multiple teams of the professional peloton to integrate power meters into their training and competitions.

Although gradually more professionals have begun to use power metres, this had little negative impact on fans of the Tour. In 2004, during the Tour de France, power metres was used for the first time to see the competitors heartbeat, cadence and power output, while they were riding, live on television.

2008: ANT +

The last big innovation for both professionals and amateurs was the release of wireless power metres. In 2006, SRM worked closely with Dynastream (the inventor of the ANT connection) to streamline the Power Protocol used for the ANT+ wireless code, which eventually allowed SRM to cut the cords on its power metres. (ANT+, just like Bluetooth Low Energy, requires little power to operate, and is perfect for the kinds of sensors on wireless accessories that we install on our bicycles.)

After a two-year partnership between SRM and Dynastream, SRM launched the fully-wireless power meter 2008.

Present and the future

Since 2008 a lot has happened in the world of ​​power metres. Accuracy has increased, and battery life has been extended. Also, several (new) companies have launched themselves into the power-metre market. The resulting product competition has caused prices to drop, meanwhile new innovations keep on coming—nowadays, even Kickstarter campaigns are used to market new models.

Although a power metre is still something of a gimmick for the amateur cyclist, the end of 2018 will see production of the first bikes pre-fitted with a power metre. Soon, we will all be using this tool to learn more about our casual riding and training data, and even competition performance, if we so desire. We here at The Prologue have an inkling that in a few years every new bike will come equipped with a power metre as standard—the Giant Defy Pro 0 seems to confirm our assumptions about this emerging trend.