Using Cardio Exercise for Cardiac Problems

This is a case where a cardio exercise program was prescribed for a specific cardiac problem. The cardiac problem in this instance is Atrial Fibrillation (AF).

Atrial fibrillation happens when the nerve action potentials in the heart fire very rapidly or in a chaotic manner.  When it beats fast, the heart doesn't pump blood very well. Vital organs like the heart muscle itself and brain may not get enough blood.

If you have atrial fibrillation you may be offered a treatment choice between a) medications such as beta blockers to slow the heart rate; b) radio-frequency ablation to destroy heart tissue that may be giving incorrect electrical signals that cause the abnormal heart rhythm; or c) cardio exercise.

If you have AF, which of these would you choose?

Let’s go with cardio exercise. But what exactly kind of cardio exercise are you going to do?

There is a careful balance of the right kind of exercise helping AF and the potential adverse effects from excessive exercise. There is scant information in the literature about what kind of cardio exercise let alone what kind of protocols to administer for AF although cardio exercise in general has been an agreed upon course of care.  

So we find out on my exercise machine with a willing subject, what kinds of variables to manipulate to A) improve symptoms and physiology and B) not allow the patient to become worse.

A 20 year old female who had a history of AF, was diagnosed by her medical doctor, and who was evaluated by a cardiologist. During a report it was suggested to the patient that she either: a) take medications, b) have an ablation, or c) undergo a course of exercise. She chose exercise and to participate in a 3-week trial of directed high intensity interval training on the Myoride Exercise Machine.

We begin a 3-week course of High Intensity Interval Training which was recommended to extend to a 6-week program by her cardiologist who evaluated her inside of three weeks.

The premise we held was that specific protocols could be determined that would exert maximal high intensity exercise bursts so as to allow for the “re-normalization” of heart rate for the patient, whether that be cardio electric or metabolic or a combination of these or other factors.

We attempted several high intensity intervals such as 3, 30-second burst sessions; 4, 20-second burst sessions, and then came upon one that we feel has made a greater difference in increasing the patient’s heart rate to the maximum in the minimal time, fulfilling the premise of getting to high enough intensity bursts but not causing over-exercising of the cardiac muscle.

Keep in mind that the Myoride Exercise Machine allows for full body, complete ROM, non-weight bearing, non-impact cardio exercise and that we can adjust any exercise variable involved:  
- resistance
- velocity
- duration

As well, to determine pre and post-exercise status, we measured forehead temperature (pre) and Rate of Perceived Exertion RPE (post). The forehead temperature was measured using an infrared thermometer. The heart rate was measured with a Scosche heart rate monitor and data was plotted using the HeartZones App.

We found that the most influential protocol, only based on my experience and the patient’s response was:

1. first interval 40 seconds, enough time to get HR up to an average of 150 bpm;  
2. next 10 intervals at 10 seconds;

Whereas the 10x10 intervals were inside the 40 second burst. In other words, we did not allow the heart rate to fully recover before we began another exercise burst. As we came upon this particular HIIT protocol, my objective was to keep the HR up and not allow it to return to resting before another work interval began.

The two following heart rate graphs were two sessions; the first on May 1, the second on May 6.

Notice on the first graph that the heart rate was not allowed to drop into a resting HR (although it did  in several cases). After the first HR spike, the following HR spikes followed roughly 20-30 seconds of rest interval -- the heart rate was not allowed to recover.

At no time during this kind of HIIT session did the patient feel poorly, nor did symptoms appear.

Notice the HR data on May 6. Here we see the heart rate continue climbing during each work interval. Interestingly, on May 6, her forehead temperature pre-workout was the highest it had been measured before any session – she wasn’t feeling well and was unwell the following day. Her beginning HR, which was lower than normal, showed signs of inefficiency but continued climbing throughout the session. This is certainly not typical heart rate of a HIIT session. In the future, any abnormal pre-exercise markers, like the high temperature in her case, should stop any exercise.

Once again, biometrics are used to determine the status and progress of the cardio workout and the physiology of the exerciser. Future testing with an electrocardiogram or other measures will help determine the outcomes of this and any other kind of protocols.

In the meantime, we continue testing specific protocols and advancing cardio exercise and HIIT in particular. We continue working on HIIT protocols to elicit specific outcomes. Because of the advantage of the manipulating exercise variables such as velocity, duration, and intensity on the Myoride Exercise Machine, we will soon be able to dial into the protocols that are most advantageous to the outcomes we are expecting.

This comes by way of hypothesis and proving or disproving the hypothesis when it comes to gain the most through exercise.