The Race Trainer digital heart rate monitor includes a linked interval timer with training zones that acts like a personal coach. This 10-workout memory HRM can be upgraded to work with a Timex on-line training log powered by TrainingPeaks . Wear your heart rate monitor to . . . Track your activity level…Maintain a healthy lifestyle…Intensify your workouts. The lightweight Digital Heart Rate Sensor features an adjustable elastic strap and a replaceable battery.