What good does a blood pressure reading do if you are sitting down with a perfect 120/80 but once you start doing activity’s it rises 10-20 values. Considering that we are active most of the day would the higher values be bad for our body?
In: 5
I’m sure there are other reasons, but it is difficult to get a reading with a lot of movement.
It’s a lot harder to read blood pressure during activity, since the cuff needs to remain in long enough to read both systolic and diastolic pressure. Plus, the normal value is calculated on the assumption that the person is at rest. If it was normally read during exercise, the expected values would be based on that instead.
Readings while active depend substantially on *how* active you are. You get much better consistency by measuring with minimal activity because that’s easy to quantify.
As others have mentioned, the answer has to do with the difficulty in accurately measuring. But difficulty alone is not the full answer, as it also had to do with something called baseline values. In order to even establish what a normal blood pressure is, we have to test a LOT of people (like tens of thousands). Now, to get a value for the healthy range we’d have to make sure everyone is exerting themselves equally as hard, say 70% of max performance. How do you ensure that everyone is at exactly 70%? It’s far, far, FAR, easier to simply tell everyone to stay at rest and measure this value to establish the baseline value. A number on its own with no context is meaningless, and you get the most context with a resting BP.
Bonus: 120/80 is actually the MAX BP that is considered healthy, not a target value. Ideally you’d be a bit under this, maybe 110/70.
Think of it like a car, if your car is parked while on and the RPMs are high that’s not good, but when you’re driving they’re expected to be higher than not moving.
Same thing with people, if you are currently active and your blood pressure is towards the height of the upper ranges, let’s say 180/110 , that’s not out of the ordinary. If you are still and inactive and have that same reading, you have high blood pressure and may have a risk of a problem or could be diagnosed with a condition.
What you need is a baseline level, your blood pressure can change dramatically with activity which reflects more on the activity than what your true blood pressure is. So you could potentially always get a high reading if you did a specific activity, which would tell you more about the activity than your blood pressure. https://youtu.be/aO5M_em6_F4
Thanks for explaining! I’ll just stick to resting, I’ve got enough trouble hitting 70% max performance. 😅👍
“Harder to read blood pressure during activity” is only part of it. If I put specialized equipment in your radial or brachial artery, I can measure your blood pressure quite accurately with each heartbeat even while you’re exercising. In fact, medical researchers have done that. Turns out, during a heavy maximum effort lift, blood pressure can go up to 300mmHg. That’s normal. Your blood pressure is supposed to go up when you exercise. The mechanics of why it does so are beyond an ELI5 level, but rest assured that blood pressure is supposed to go up when you exercise.
The reason that BP is measured in clinical settings at rest is because that is the method used in all the clinical trials testing blood pressure medication. The whole point of measuring blood pressure is to see if you need medical treatment. To decide if you need medical treatment, I need to know if your blood pressure is abnormal. To know if it’s abnormal, I need to have a working definition of normal. That definition has to come from a consistent, reproducible measuring technique that I can do the same way over and over again for all my patients; that way I’m comparing apples to apples. So when we test blood pressure medicine in clinical trials, we measure blood pressure at rest in the trial participants because it is most consistently reproducible. If I want to decide whether you need a blood pressure medicine, I have to measure your blood pressure the same way it would have been measured in the clinical trials, so that I know I can use a reliable basis of comparison.
“Convenience” is part of the equation; standardization is the other part.
All the comments so far are useful (all aspects of raised blood pressure are relevant to our understanding) but one has been missed. Humans are at rest a lot more than we think. And research has suggested that the BP being raised most of the time consistently, could be at least as damaging to the blood vessels as the spikes associated with activity. Both are important
Because you’re resting BP is your baseline. You have to know the baseline in order to gauge function. It also is going to have the least amount of factors influencing it. blood pressure SHOULD rise and fall depending on how active you are. Lower when you’re sleeping, higher when you’re exercising. but if you don’t know your starting point, how could yo possibly tell how MUCH it changes in other situations if you ever needed to?
Latest Answers