No Power, No Problem

If you don’t have a power meter, you can compare your heart rate and speed in riding situations with fairly regular conditions. For example, monitoring your speed on a trainer that is set up properly will work. If you can hit higher speeds, those are good indicators of an improvement in your fitness. If you have a long, steady climb, your speed on that stretch of road can also show you if you are getting fitter, especially when checked against your heart rate.