Powermeters for professional-level power tracking. Cadence and heart rate measurement have been options on bike computers for quite some time and are helpful for targeted training. The exact wattage measurement at the cranks though has been something for the experts until relatively recently. Pedals and cranks with integrated wattmeters from brands such as Sram, Rotor, Garmin, Polar and Look are now much more accessible for the rest of us. They allow a precise and objective load control in training and competition, most work with the ANT+ radio standard, send the live performance data to your wireless computer and of course allow a detailed analysis of your training data on the computer.