Hearth Rate:

A general guideline for categorizing heart rate based on severity using beats per minute (BPM):

1. Resting heart rate: Normal range is between 60 and 100 BPM. A resting heart rate below 60 BPM is considered bradycardia, while a resting heart rate above 100 BPM is considered tachycardia.

2. Exercise heart rate: During exercise, a target heart rate may be recommended based on age and fitness level. A target heart rate between 50% and 70% of maximum heart rate is typically recommended for moderate-intensity exercise, while a target heart rate between 70% and 85% of maximum heart rate is recommended for vigorous-intensity exercise.

3. Maximum heart rate: Maximum heart rate is calculated as 220 minus the person's age in years. This is the maximum number of times a person's heart should beat per minute during exercise.

It's important to note that heart rate may vary depending on the individual's age, fitness level, and other factors. Additionally, some medications and medical conditions may affect heart rate. If you are concerned about your heart rate or if you experience symptoms such as chest pain, shortness of breath, or dizziness, it's important to seek medical attention.

References:

1. American Heart Association. (2018). All About Heart Rate (Pulse). Retrieved from https://www.heart.org/en/health-topics/high-blood-pressure/the-facts-about-high-blood-pressure/all-about-heart-rate-pulse

2. Mayo Clinic. (2021). Tachycardia. Retrieved from https://www.mayoclinic.org/diseases-conditions/tachycardia/symptoms-causes/syc-20355127

3. Mayo Clinic. (2021). Bradycardia. Retrieved from https://www.mayoclinic.org/diseases-conditions/bradycardia/symptoms-causes/syc-20355474

4. American Heart Association. (2020). Target Heart Rates Chart. Retrieved from https://www.heart.org/en/healthy-living/fitness/fitness-basics/target-heart-rates