Do you know how your medications work? Athletes and beta blockers

This article is motivated by some incidental conversations I've had with fellow athletes in recent times regarding dissatisfaction with their own medication regimes. The use of beta-blockers, in particular, for managing hypertension (high blood pressure) or arrhythmia (irregular heart beat) in athletes has cropped up a few times. 

Here, I give an overview of beta blockers and set out some of the salient issues for athletes who are on beta-blockers. If this topic bears some relevance to you, then I hope this information will inspire healthy and constructive dialogue with your treating doctors.

Please remember, the information on this site isn't intended as a substitute for professional medical advice.  Please consult your doctor for specific help with your own health.

Athletes' frustrations with beta blockers

Athletes' personal experiences with beta blocker medications, across a range of sports, can be found in various forums across the internet. Some of these accounts by athletes may resonate with you:

Posted by insanedad, June 27, 2005, at Slowtwitch Triathlon Forum: "This may sound strange but in my races I did last year, I would always feel like my heart just couldn't keep up with my body [ ...] It was as if my heart hit a wall and would not allow me to go any faster."

Posted by Phil K, August 23, 2013, at Runner's World Forum: "The past six weeks I have had a series of very difficult training runs [...] I started to have wild thoughts like 'age was setting in', and that 'my time for crisp competitive running was over'. The sluggish workouts, the physical unresponsiveness, started to affect me psychologically ... "

Posted by slowmo, May, 2012, at Marathon Swimmers Forum: "You will have this feeling as though your arms and legs are really heavy [...] The drug acts like a throttle."

Posted by Schwingding, June 27, 2005, at Slowtwitch Triathlon Forum: "I was like a limp noodle out there on the bike. I could go long distances at an easy pace just fine, but I just could not work at all at higher effort levels. It was like someone had put a rev limiter on me."

Posted by Theo, April 2013, at Marathon Swimmers Forum: "I still experience the heavy arms and inability to swim the sets I want if I take the medicine prior to the workout." 

What are beta blockers?

Beta blockers are drugs that regulate your heartbeat. They block the action of the hormone in your body called adrenaline (also known as ephinephrine). They do this by preventing the normal binding of adrenaline to so-called beta receptors on nerves in your arteries and heart muscle. Beta receptors control heart rate and the strength of its contractions, and influence blood pressure.

Taking beta blockers will cause your arteries to become wider (arterial dilation) and decrease your heart rate and strength of its contractions these effects will lower your blood pressure. Put simply, your heart's demand for oxygen and blood are reduced as your heart does not have to work as hard to pump blood throughout your body.

Some examples of beta blockers

There are a variety of beta blockers being prescribed today in clinical practice. They usually end in 'olol' or 'alol' on your medication lists, although there are a number of different brand names. Some examples are:

•     generic name            e.g., brand name
•     metoprolol                 e.g., Lopressor, Toprol, Betaloc
•     labetalol                     e.g., Normodyne, Trandate
•     carvedilol                   e.g., Coreg
•     propranolol                e.g., Inderal, Bedranol

Brands of beta blockers

Brands of beta blockers may have different availability and approval classifications in different countries, which can make looking them up on the internet quite challenging. I am aware that most of you accessing this page reside in Australia. If you wish to take a closer look at the different beta blockers, I recommend you access this resource "All about heart medicines" at Heart Research Australia, which is specific to medications available in Australia. Refer to the section on beta blockers. Of course, you should always consult with your doctor about your medication queries relating to your own heart health.

Selecting the right beta blocker

The choice of beta blocker depends on the medical condition being treated because beta blockers, although similar, differ in their action. For example, research cites  different actions, including duration of effect (3 hours to 22 hours), the types of beta receptors they block (1-selective or 1/2-nonselective), etc. Your doctor will take into account your medical condition and lifestyle factors when selecting a beta blocker most suitable for you.

What medical conditions are managed with beta blockers?

High blood pressure is the most common cardiovascular problem discovered in athletes, according to Dr Larry Cresswell at Athlete's Heart Blog. Beta blockers are used to treat various conditions, including high blood pressure.

Here is a list of conditions typically treated with beta blockers. Source: The Mayo Clinic

•     High blood pressure
•     Irregular heart rhythm (arrhythmia)
•     Heart failure
•     Chest pain (angina)
•     Heart attacks
•     Glaucoma
•     Migraines
•     Generalised anxiety disorder
•     Hyperthyroidism
•     Certain types of tremors

Side effects of beta blockers

Side effects will sometimes occur in the first few weeks while adjusting to a new medication, then subside as your body adjusts to the medication regime. It is always important to communicate how you are feeling with your doctor. The following is not a full list of possible side effects but mentions the main ones that may occur. Source: The Mayo Clinic
Common side effects

•     Fatigue
•     Cold extremeties
•     Headache
•     Upset stomach
•     Constipation
•     Diaorrhea
•     Dizziness

Less common side effects

•     Shortness of breath
•     Trouble sleeping
•     Loss of sex drive
•     Depression

Beta blockers can be a poor choice for a competitive endurance athlete

The calming effect of beta blockers makes them attractive for some athletes whose performance depends on balance (e.g., gymnastics) or a steady hand (e.g., archery, shooting). This use of beta blockers by athletes contravenes the World Anti-Doping Agency (WADA) guidelines on the use of medications or substances for athletes during competition.

For endurance athletes, beta blockers will affect your workouts in several ways and can trigger a range of undesirable symptoms.

Reduced exercise performance

Beta blockers will reduce your exercise performance by decreasing either maximal heart rate or the strength of your heart contraction, or both. Your cardiac output (the volume of blood pumped by your heart per minute, mL blood/min) and VO2 max (the volume of oxygen you can consume while exercising at your maximum capacity, measured in millilitres per kilogram of body weight per minute, ml/kg/min) are compromised. This will create that sensation of sluggish workouts and physical unresponsiveness.

Increased perception of exertion

Beta blockers can give you an increased perception of exertion because they slow your heart rate and prevent an increase that typically occurs with exercise. You may struggle to work out at previous heart rate levels before taking beta blockers and may never reach your previous target heart rate.

Postural hypotension

Beta blockers might make you feel lightheaded, dizzy or faint when standing up too quickly. You may have trouble climbing stairs or bending over.

Impaired temperature regulation

Beta blockers slow the heartbeat and so limit the body's ability to circulate blood fast enough for heat exchange at the skin's surface. Beta blockers can therefore impair your temperature regulation during prolonged exercise, predisposing you to dehydration and hyperthermia. This is something for athletes to consider when training or racing in hot weather.

Ways to minimize the effects of beta blockers on your athletic activities

Sometimes, athletes will have to weigh up the pros and cons of beta blocker therapy and many will end up making the decision to take a beta blocker. Despite the disadvantages to sport performance, the overall improvement in quality of life and/or reduction in the risk of having an adverse event can make taking a beta blocker the best line of heart health management. It's all about taking into account the data relating to your own circumstances and making a personal risk assessment that enables you and your doctor to decide on the most appropriate therapeutic course of action for you.

If you are taking a beta blocker and remain keen to participate in sport activities, here are some tips that might help you on your sport health journey.

Focus on 'participation' not 'racing'

The shift in mental attitude from 'competitive athlete' to 'sport participant' can be on of the most significant changes an athlete must make when diagnosed with a cardiac condition and/or facing life long medication therapy. This transition may not be easy for some athletes and will be a gradual process to work through, as described by an athlete called Sue  at Pacemaker Club.

Posted by Sue, 29/08/2013, at Pacemaker Club: " ... it's caused me to face a changed self-image as a runner. I'm not the runner I was, and I don't think I ever will be. I don't get faster or stronger anymore. I do think it's the ICD and not the beta blocker, although I could be wrong. I'm gradually changing my expectations for myself, and telling myself that I'm damn lucky that I'm even alive, never mind able to run. But it's a difficult transition; so much of my self-pride has always been wrapped up in being a runner for so many years."

Another athlete, Tracey E, accepts the shortcomings of beta blockers, flipping what might be perceived as a negative outcome ("I may be the slowest and the last") into a positive accomplishment ("I do finish and I figure that puts me ahead of the most of the population").

Posted by Tracey E, 29/08/2013, at Pacemaker Club: "I do Crossfit. I can definitely tell a difference and I do feel the bb holds me back, but I don't let it stop me. I remind myself that without it I can't work out at all so suck it up buttercup :) I may be the slowest and the last done many days, but I *do* finish and I figure that puts me ahead of most of the population." 

Reset your heart rate monitor settings

If you are wanting to use a heart rate monitor to guide your workouts, you can consult a doctor to calculate a readjusted target heart rate for you to work to. This usually requires a baseline exercise stress test to measure how hard your heart pumps while taking beta blockers.

Alternatively, you can use a Rate of Perceived Exertion (RPE) scale, which uses your judgement of how hard you are exercising (based on effort, breathlessness and fatigue). With an RPE scale, you can learn to regulate your effort to gain maximum benefit from your workout.

One rule of thumb: If you can't talk while exercising, you are probably overdoing it .

Rate of Perceived Exertion (RPE) Scale:

Change your warm up strategy

A longer and more gradual warm up and cool down are advised for athletes on beta blockers, to minimize medication side effects.

Schedule your medicine intake around your workout

Please be careful: you should discuss your medication scheduling with your doctor before making any changes.

The testimonials of many athletes suggest you might try taking your beta blockers either well ahead of or immediately after your training sessions, so that you have the least amount of the medication in your system when you are exercising.

Posted by slowmo, May 2012, at Marathon Swimmers Forum: "Yes, I was getting ready for the sears stair climb ended up on a beta blocker and went from running 2,000 to 3,000 steps down to 700 during my workouts. The drug acts like a throttle so what I learned was to take my meds after my workouts, this way I hit the 23hr mark of it being in my system which let me workout at higher rate if that makes sense."

Posted by Chris OD, September 2012, at Marathon Swimmers Forum: "Take the medicine after the workouts so the exercise performance is least affected. If one takes a beta blocker before an exercise session (especially a short-acting beta blocker), one will feel like one's heart is pumping so hard it wants to beat right out of one's chest. The pulse will be slower than normal, and will not rise accordingly to allow for the body's need for the heart to provide more oxygen to the muscles [...] Personally, if I were taking a beta blocker, I would take a long-acting, once daily dosage form, after my workout each daily: atenolol."

Posted by Snail, 10/07/13, at Runners World Forum: "I have subjectively noticed a difference between when I take and don't take the beta blocker the AM before a tempo run. So I have adjusted the way I take it. I used to take it first thing upon awakening, but will now wait until after my run, depending on what time of day that is, so my run will be at the tail end of the therapeutic effect when it won't have as much of an effect on my heart rate. I also may skip it the day before a race, though I would obviously not advise this for anyone else without speaking to their doctors."

Warning: Do NOT suddenly stop taking a beta blocker!

You should not abruptly stop taking a beta blocker because this may actually trigger chest pain, irregular heart rhythms or a heart attack. Consult your doctor if your beta blocker is not working for you or causing you unpleasant side effects. Weaning off beta blockers must be done under careful supervision.

What about having a conversation with your doctor?

What I find surprising is the number of endurance athletes who take exactly what their doctors tell them to take and don't ask any questions about their medications. And, the same athletes won't necessarily connect symptoms they might experience with medication side effects. If they do draw a connection, then they may err towards medication non-compliance; in other words, they may avoid taking their medication altogether or only sporadically.

So what about having a conversation with your doctor? Well, many athletes express dissatisfaction with doctors who appear clueless about the significance of accommodating a sport lifestyle into their patient's personal health management plan.

I would encourage you to be completely open with your doctor or cardiologist on the level of exercise that you do. Your idea of 'moderate' might be a cardiologist's idea of 'strenuous'. It is important that you explain clearly to your doctor your lifestyle expectations. Talk about other drug options (e.g., ACE inhibitors, calcium channel blockers, etc.). Seek a referral to a sport physician if you feel your own doctor is not accommodating your needs. A second opinion can be reassuring.

World Anti-Doping Agency (WADA) listing

Beta blockers are included in the World Anti-Doping Agency (WADA) listing of medications or other substances banned for use by athletes during competition, in specific sports and under certain conditions. You and your treating doctor need to be aware of WADA restrictions if you choose to use medications on the prohibited list. Refer to the 2016 Prohibited List, available for download from the WADA website.
A useful fact sheet

The Atrial Fibrillation Association (AFA) Australia has produced a very useful information sheet on beta blockers which you can access at their website, here.

Author: Kara Gilbert @ KMG Communications

The post Do you know how your medications work? Athletes and beta blockers appeared first at Heart Health for Athletes.