The newest power meter on the market is the Ergomo, also made in Germany. The Ergomo measures power differently from the units reviewed above in that it measures the torsion, or twisting, of the bottom bracket spindle. Every time you pedal, there is a small amount of twisting that occurs on the spindle, similar to the twisting that might occur with a wet towel if you twisted it into a whip. The Ergomo contains an optical sensor that allows it to measure the distance the axle twists, and from this distance it calculates the torque and the corresponding watts that are being applied in order to make that caliber of a twist. A complete Ergomo consists of the Ergomo bottom bracket and crankset.

The downside of an Ergomo is the sensor measures power at the bottom bracket spindle, resulting in a measurement of the side that twists—the left side. The right side of the spindle is attached to the crankset so there is no real twist on the right side. The Ergomo can only measure the rider’s left leg power accurately. Ergomo takes the power output from that left leg and doubles it in order to get your wattage. This may seem to be a problem, but in reality it has not proven to be one for a majority of the users. Only cyclists with a big discrepancy in the strength of their legs would have inaccurate reading. Every rider has a small discrepancy in leg strength, but this discrepancy is usually less than 5 percent.