When you’re fifteen years old, your target heart rate range is between 140 and 170 beats per minute. This number will gradually increase with age until it reaches the adult level of 60 to 100 BPM in your twenties. If you want to know what your target heart rate should be right now, take a deep breath! We’ll calculate it for you. To start off our calculations, we need to determine how fast one’s heartbeat should beat at rest – that means not exercising or exerting any physical effort whatsoever. A person who has just woken up from sleep typically has a resting heartrate around 72 bpm (beats/minute). People who are overweight may have this figure higher than someone who exercises regularly because they might have more weight for their heart to pump around. The person’s target heart rate range is between 140 and 170 beats per minute, so the equation will be: 72 – (170-140) = 104 bpm. As you can see, your resting heartrate has a lot of bearing on how fast it should beat during other activities like exercise or physical exertion! This number will gradually increase with age until it reaches the adult level of 60 to 100 BPM in your twenties. If you want to know what your target heart rate should be right now, take a deep breath! We’ll calculate it for you. To start off our calculations, we need to determine how fast one’s heartbeat should beat at rest – that means