If you’re on a journey to improve your health and fitness level, you’re probably preoccupied with taking the necessary steps toward this goal. This is a good thing. But how do you know what’s happening in the background or whether or not your body is responding to your health-promoting interventions?
Understanding normal vital signs is a good place to start. Vital signs can help you assess wellbeing, detect underlying problems, and motivate lifestyle changes. It’s easier to make progress if you have health indicators you can measure and keep track of. This blog post will dissect the intricacies of normal vital signs, why they matter, and how you can keep track of them. Read on to learn everything you need to know.
What Are Normal Vital Signs?
Normal vital signs are a set of metrics that provide information about how well your body is functioning. Having this information allows you to track your health, see the trends, and proactively identify possible problems. You can also use this information to optimize your athletic performance.
The four classic vital signs are heart rate, respiratory rate, blood pressure, and body temperature. Pulse oximetry is now regarded as the fifth vital sign.
Although everyone has different vital sign measurements, most people fall into the predetermined normal ranges. These are the ranges that are considered healthy for most individuals. If your vital signs constantly fall outside of these ranges, you may be experiencing suboptimal health. If they fluctuate from your baseline, you may have an illness or medical condition.
To properly read vital signs, it’s important to understand what they mean. Here are the five vital signs you need to know about.
1. Heart Rate
Simply put, your heart rate refers to the number of times your heart beats every minute. Each time your heart contracts to pump blood, this is considered a heartbeat. A lower heart rate means your heart pumps more blood with each contraction and easily keeps a regular beat. On the flip side, a high resting heart rate may mean your heart works extra hard to pump blood.
The normal heart rate ranges between 60 and 100 beats per minute. Even within the normal range, it’s important to note that everyone has their limit of what is considered “normal.” Thus, it’s always best to discuss any changes with your healthcare provider if you are concerned about your heart rate.
Factors that affect your heart rate include:
- Body size
- Activity level
- Medical conditions
- Emotional status
You can track your heart rate using wearables, such as wrist/arm devices or chest straps. These devices use optical sensors to detect blood flowing through your veins. The accuracy of optical-based wearable devices is still subject to debate. One study showed variable accuracy of different optical-based heart rate monitors during aerobic exercise.
Chest straps are considered more accurate because they are more responsive to the tiny variations in your heart rate. They use electrocardiogram (ECG) sensors. An ECG is a device that measures the electrical activity of the heart. Chest straps are also more stable, and this reduces signal interference, thus improving their accuracy.
Apart from knowing your heart rate, it’s also important to keep track of your heart rate variability. Heart rate variability refers to the variation in time between successive heartbeats. This metric is measured by many wearables today and can help you optimize your fitness routine.
2. Respiratory Rate
The respiratory rate refers to the number of breaths you take per minute. For adults, the normal respiratory rate ranges between 12 and 20 breaths per minute. A rate that’s lower than the range means your breathing is slower than normal. A rate that’s higher than the range means your breathing is faster than normal, and you may experience shortness of breath.
Abnormalities in respiratory rate indicate changes in body physiology or underlying health problems.
Factors that affect your respiratory rate are:
- Emotional status
- Medical conditions, such as asthma and pneumonia
Measuring your respiratory rate is as simple as counting the number of times your chest rises every minute. But this can be inaccurate especially when you get anxious during the process.
3. Blood Pressure
Blood pressure measures how hard your blood is pressing against the walls of your arteries. Low blood pressure means that your heart is not contracting strongly enough or your plasma volume has reduced. A high blood pressure implies increased contractility, narrowed blood vessels, or fluid overload.
Blood pressure readings include two measurements: systolic pressure and diastolic pressure. The systolic blood pressure is taken when the heart contracts, while the diastolic blood pressure is taken in between beats. Blood pressure is measured in millimeters of mercury (mmHg) and is expressed as two numbers with a slash between them (e.g., 115/75 mmHg). You will sometimes hear healthcare professionals read a blood pressure as the top number "over" the bottom (such as “115 over 75”). The top number is your systolic pressure, and the bottom number is your diastolic pressure.
The normal blood pressure for a healthy person is defined as a systolic pressure lower than 120mmHg and a diastolic pressure lower than 80mmHg. High blood pressure is called hypertension, while low blood pressure is called hypotension. Very high or very low blood pressure may be the sign of a medical emergency. When blood pressure is too high, the arteries have a difficult time resisting blood flow, which makes the heart work extra hard.
Blood pressure is affected by:
- The time of day
- Stress and anxiety
- Alcohol and tobacco use
- Medical conditions, such as heart disease
Your blood pressure is one of the most important metrics you should monitor. High blood pressure typically shows no symptoms until it’s elevated to dangerous levels. Low blood pressure is characterized by dizziness, blurred vision, fatigue, and fainting.
There are a ton of at-home blood pressure monitors on the market today. To ensure you’re getting the right device, look for one that is clinically validated and FDA-approved.
Blood pressure monitors can either be attached to the upper arm or the wrist. To measure blood pressure, they contain an inflatable cuff that exerts enough pressure to prevent blood flow in the underlying artery. A pressure sensor detects systolic pressure at this point. The cuff is gradually deflated and the diastolic pressure is taken when blood flow is no longer restricted.
Remember, it’s important to learn how to correctly measure your blood pressure so that you get accurate readings.
Body temperature is a vital sign that we’re almost always aware of. Your body temperature can provide a clue to infection, medical conditions, or inflammation. Body temperature is controlled by the part of the brain called the hypothalamus. The hypothalamus regulates temperature by responding to the body’s signals. For example, when you’re infected with a virus, your immune system sends signals to the hypothalamus to increase body temperature and weaken the infection.
Your body temperature varies throughout the day. It’s lowest in the morning and highest in the afternoon. For this reason, it’s better to check it at the same time every day.
According to most sources, the normal body temperature of a healthy person is, on average, 98.6 degrees Fahrenheit (37 degrees Celsius). However, temperatures in the range of 97.8 and 99.1 degrees Fahrenheit (36.5-37.3 degrees Celsius) are acceptable.
When your body temperature is high, you have a fever. When it is low, it’s referred to as hypothermia.
The factors that affect body temperature include:
- Your environment
- Physical activity
- Hot or cold food and beverages
- Medical conditions, such as thyroid disorders
- Infections, such as the flu
Body temperature can be measured using a digital thermometer. It can be measured in the mouth, armpit, and rectum. In general, oral and rectal temperature measurements are more accurate than axillary temperature.
Far from digital thermometers, temperature-sensing wearable devices can help you keep track of your temperature. Their biggest disadvantage is that they measure skin temperature rather than core temperature, which may vary slightly.
5. Pulse Oximetry
Pulse oximetry has been referred to as the fifth vital sign. Healthcare providers all around the world now take pulse-ox measurements as part of regular patient examination.
Pulse oximetry measures the oxygen levels in your blood, also called oxygen saturation. Oxygen saturation reflects how well your red blood cells are carrying oxygen. It can be affected by several medical conditions, such as respiratory and heart disease.
The normal oxygen saturation limits range between 95% and 100%. A reading less than 95% is abnormal, while less than 92% is linked to poor outcomes and requires medical intervention.
Pulse oximeters are attached to the finger. They use optical sensors to detect the oxygen levels in the blood. A couple of fitness wearables, like the Apple Watch Series 6 and Fitbit Versa 2, now offer oxygen saturation measurements, but their accuracy is still subject to debate.
Normal Vital Signs: The Key to Health Optimization
Normal vital signs provide important data that can help you optimize your health. There are the four main vital signs you need to know: heart rate, respiratory rate, blood pressure, and body temperature. Pulse oximetry is considered the fifth vital sign. Tracking your vital signs has never been easier with digital monitors and wearables.
In general, normal vital signs are affected by your age, sex, body weight, fitness level, medical conditions, and medications. It’s important to keep track of your vital signs over time, establish your baselines, and take action.
For example, with COVID, many people who tracked these vital signs could see significant changes in their metrics before the onset of symptoms. This can be applied across many potential illnesses or diseases. Seeing these metrics helps surface potential issues ahead of time.
The normal vital signs for healthy adults fall within the following ranges:
- Blood pressure: Less than 120/80mmHg
- Respiratory rate: 12-18 breaths per minute.
- Heart rate: 60-100 beats per minute.
- Temperature: 97.8°F to 99.1°F (36.5°C to 37.3°C)
- Pulse oximetry: 95-100%
If you’re looking to optimize your health by monitoring your normal vital signs, sign up with Vital today. Integrating all that data can be difficult. Vital makes it easy for you to connect all your data from wearables to fitness trackers to continuous glucose monitors in one place.