“Help! One of my Indoor Cycling students told me that he is taking meds for his blood pressure, and he”™s asking questions about what this means for his training. I have no idea! What should I know about this?”
- K.P., Phoenix, AZ
Melissa Marotta writes:
Since ICI launched its medical research column, we have received dozens of questions from instructors all struggling with the same issue: “How do blood pressure-lowering (“antihypertensive”) medications affect the “bread and butter” of what we do?” Yours is an extremely common predicament, and we congratulate you for empowering yourself to seek out the information you need to best serve your clients.
While many group exercise instructors and personal trainers are certified through programs designed to prepare them to train folks without major medical problems (with perhaps cursory mention of some common medication names on a single page in a manual), it doesn”™t take long before they get thrown a curveball. And while we may be very responsible in a) providing information limited to the scope of our expertise and b) securing that a client has received physician approval before engaging in exercise, this doesn”™t do much to alleviate the anxiety we feel in that moment where we haven”™t a clue how to even begin to answer the question at hand.
This article is not meant to take the place of advanced certification in working with special populations; however, I hope it will be a helpful reference to acquaint you with how to approach a rider who asks you how to make sense of how antihypertensive medications may impact training.
What is Hypertension?
Hypertension, or high blood pressure, affects approximately 58 to 65 million people in the United States. One study estimated that it is the most common reason that non-pregnant U.S. adults to visit doctors”™ offices and use prescription drugs. No wonder we see people struggling with this so frequently in our classes!
Normal blood pressure is defined by a systolic blood pressure (when the heart is contracting) of < 120 mm Hg, and a diastolic blood pressure (when the heart is relaxing/filling with blood to later pump) < 80 mmg Hg. We call it “pre-hypertension” for pressures ranging from 120-139 systolic/80-89 diastolic. Hypertension, then, is when blood pressure is â‰¥140/â‰¥90 mmHg, and can be further stratified by severity.
Hypertension can either be due to an underlying cause (“secondary hypertension”), or is otherwise qualified as “essential” or “primary” hypertension. Risk factors for primary hypertension include excessive salt (sodium) intake (if additional factors are present), family history, high cholesterol, obesity, excess alcohol intake, and others. Potential causes for secondary hypertension include kidney disease, chronic NSAID use , adrenal or endocrine disorders, and untreated sleep apnea.
Why does it matter that blood pressure is elevated? In my training as a future physician, this is something about which I see so many doctors do a sub-ideal job in educating their patients. “We have to lower your blood pressure!” Why? We care because consequences of long-standing hypertension are awful. First off, it is the #1 risk factor for stroke. Other potential consequences are premature cardiovascular disease (a worse risk factor than smoking, high cholesterol, or diabetes, at that!), heart failure, arrhythmias, sudden cardiac death, death after heart attack, intracerebral bleeds, and dialysis-requiring renal disease.
Treatment of Hypertension
When a patient has elevated blood pressure during a doctor”™s office visit, the first thing we ask them to do is to collect their own blood pressure measurements at home. Some people”™s pressures increase just by being at the doctor”™s office — “White Coat Hypertension,” we call it. But assuming that the elevated pressures are consistent, we begin by encouraging non-medication lifestyle interventions: decreased dietary salt intake (< 100 meq/day), increase aerobic exercise, weight loss, moderate alcohol intake (1-2 drinks can be helpful; > 2 drinks is associated with increased hypertension). We also encourage people to quit smoking — not because it lowers blood pressure but because the combined effects on cardiovascular health are extremely risky. We also evaluate for secondary causes and monitor for evidence of organ damage (eyes, heart, kidneys, etc.)
If blood pressures do not normalize to a target of < 140/90, however, we begin to consider recommending medications to minimize the complications I described above.
What gets confusing is that there are a wide number of different classes of medications that are used to reduce blood pressure, and a number of different drugs (which each may have 3-4 different brand names per each generic equivalent) within each class. Treatment usually begins with one drug; if that one drug fails, combinations of drugs (or even combination-drugs!) may be used. Not surprisingly, patients (let alone their indoor cycling instructors) may have a very difficult time keeping it all straight.
In general, the most common classes of medications used in the treatment of hypertension include:
* Loop diuretics
* Thiazide diuretics
* Potassium-sparing diuretics
2) Vasodilators (dilate vessels)
* ACE inhibitors
* Angiotensin receptor blockers (ARBs)
* Calcium channel blockers
* Alpha-adrenergic antagonists
* Direct arterial dilators
* Renin inhibitors
3) Cardioinhibitory drugs
* Beta blockers (link to https://www.indoorcycleinstructor.com/indoor-cycling-20/melissa-marotta/beta-blockers-qa/)
* Calcium channel blockers
4) Alpha-adrenergic drugs
* Alpha-1 blockers
* Alpha-2 agonists
Typically, treatment will begin with one of either a thiazide diuretic (unless in the presence of renal disease), a long-acting calcium channel blocker, an ACE inhibitor, or an angiotensin receptor blocker. If treatment with a single drug does not sufficiently control blood pressure, these drugs are often used in combination.
Each class of medications is different, and some have unique effects on issues we very much care about during exercise (i.e., beta blockers affect heart rate; ACE inhibitors do not). So it is important to understand the class to which your client”™s medication belongs.
From there, I will describe what to expect from the most common classes of medications that you are likely to come across. Hopefully, this will be a good, digestible starting point.
Approaching Your Client Who Takes Antihypertensive Medications
As a stickler for “structure,” I will attempt to provide a methodical approach describe how instructors can approach their riders who take antihypertensive medications methodically.
Step 1: “Have you spoken with your doctor about exercise? Does he or she have any specific recommendations for what is safe and unsafe for you?”
If the client has not had this conversation, encourage them to do so- specifically, are there heart rates they should not exceed? Many physicians have no idea what indoor cycling classes are like, and no idea how elevated one”™s heart rate is likely to become without specific training and encouragement to pace one”™s self.
Step 2: “What kind of blood pressure-lowering drug are you taking?”
In many cases, your rider will not know their drug”™s class. He or she is most likely to know the name of the specific drug; in many cases, only the brand name (which may be more difficult for you to identify the class by the mechanism I will teach you). You can Google the brand name to find the generic name, or even to directly find out the drug”™s class.
Here are a couple of short-cuts for figuring out the drug class by using a drug”™s generic name:
* ends in “pril” = ACE inhibitor
* ends in “lol” = beta blocker
* ends in “tan” = ARB (bonus: ARB”™s brand names often end in “zaar”)
Step 3: “I encourage you to speak with your doctor about what you might commonly expect to happen during exercise while you are taking this medication. But in general, here”™s what I do know…”
Please click here for a printable PDF reference of many common antihypertensive drugs that your riders may be taking. Bring this with you to class for easy reference. The chart includes select classes of drugs, examples of generic names of drugs that fall within each class, information about their mechanisms of action, effects on heart rate, common side effects, and whether RPE vs. standard HR training is likely to be better option.
Step 4: What does this mean for heart-rate training?
Ah, the $25,000,000 question. I will attempt to simplify this in a way that will hopefully empower instructors to think critically and independently through this problem.
As Jennifer Sage described artfully in “Keep It Real” and as I alluded to inmy piece on the medical consequences of over-training , there are a number of factors that render heart rate monitor readings unreliable. Under conditions of illness, sleep deprivation, altitude, heat, humidity, stress, dehydration, hyperhydration, overtraining, and certain drugs (including caffeine), rate of perceived exertion is a more reliable indicator on which to base intensity monitoring.
What are these “certain medications?” Anything that does not allow normal exercise physiology to progress:
* anything that prevents an increase in heart rate
* anything that prevents an increase in sympathetic nervous system activity
* anything that prevents blood vessels to dilate and increase delivery of oxygen to working muscles
You”™ll note that I haven”™t described any examples of the last one. I”™ve only included it so that you can think about it. But as for the first two, I bet you can figure it out for yourself.
Which antihypertensive medications are likely to affect heart rate?
*STOP* Try going back to my chart in Step 3. Think about it for a few minutes, then continue reading.
Please see my article on beta blockers for a description of how a client may report feeling when they attempt to push themselves “hard” or “very hard” during exercise.
Research shows that when athletes are taking medications that suppress heart rate and contractility, training should be based on perceived exertion rather than heart rate.
Step 5: If your client complains of discomfort during exercise, encourage them to see their physician.
I usually explain to people that sometimes if a certain blood pressure-lowering medication is having an effect during exercise that makes a person uncomfortable, a different type of medication might not have the same effect.
“I encourage you to speak with your doctor about why he or she recommended this specific medication for your specific needs, and to collaborate on a way to balance your very important concerns.”
Given the sheer volume of different choices of antihypertensive medications, physicians consider a wide number of factors before recommending treatment options — including history of treatment and response to treatment (both the person themselves and their family), additional medical conditions, drug-drug interactions, and side effect profile. For example, ACE inhibitors have been shown to slow the progression of chronic kidney disease (particularly in patients with diabetes mellitus-type II); for those patients, ACE inhibitors are generally recommended to treat their hypertension. Diuretics are the best option when someone is also suffering from congestive heart failure and/or have fluid accumulating in their legs or elsewhere. Beta blockers have been shown to protect the heart after myocardial infarction (commonly referred to as a heart attack), and have been shown to be beneficial for unrelated conditions from which your client may also be suffering (i.e., preventing recurrent migraine, treating conditions such as essential tremor, panic, and vasospasm). Any of these factors (and others) are likely to have entered the equation when your client”™s physician recommended the specific antihypertensive medication as the best choice; however, if a particular side effect is intolerable, this warrants a new conversation. For example, serious athletes commonly feel too uncomfortable during exercise while taking beta blockers, and work with their doctors to transition to an alternative (see: my previous article here
At the end of the day, medical treatment should always be a collaborative process between people and their health care providers to navigate the challenges of the world in such a way to address their shared goals and priorities. If a particular medication becomes inconsistent with said goals and priorities (i.e., not feeling lousy during exercise), it is then up to this partnership to work together for a new solution.
The writer is a third-year medical student at the University of Vermont College of Medicine in Burlington, Vermont. She is also a certified personal trainer (American College of Exercise) and STAR 3 Spinning instructor, as well as author of the popular blog Spintastic (http://spintastic.blogspot.com), themed on motivational coaching strategies.
Have a medical research-related question or suggestion for an upcoming column at Indoor Cycle Instructor? Email Melissa at email@example.com.
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Kaplan NM, Rose BD. Choice of therapy in essential hypertension: recommendations. © 2010 UpToDate, Inc.
Kaplan NM, Rose BD. What is the goal of blood pressure in treatment of hypertension? © 2010 UpToDate, Inc.
Micromedex® Healthcare Series: DRUGDEX® Drug Point. Thomson Reuters. 2010. www.thomsonhc.com/
|Indoor Cycle Instructor Reference Guide to Common Antihypertensive MedicationsMelissa MarottaMS-III, University of Vermont College of Medicine
Medical Research Correspondent, ICI/PRO
Certified Personal Trainer, American Council on Exercise
STAR 3 Spinning Instructor