Exercise Prescription

A 40 yr old patient came in complaining that he was admitted in a secondary hospital because of a chief complaint of loss of consciousness after a strenuous exercise and was discharged as a case of urinary tract infection. He was upset at the way he was managed and that nobody explained his case to him and his family. He did not even know who and what doctor admitted him.

First, I had to address the issue of miscommunication. Many times, because of too many patients, some doctors would tend to treat the laboratory findings rather than the patient. If that was the case, I told him that he should be thankful it was UTI and not any cardiac pathology and that maybe, the doctor was just too busy to explain details of his case to him. Personally, I believe that when a patient enters my clinic, it’s not because he’s concerned with his disease but more on the anxiety surrounding the possibility of a disease.

Next, I asked if he has symptoms referable to a cardiac disease because apparently he was worried that he has a heart problem and this will disable him from doing his routine treadmill exercise and weights every morning. After careful examination, I told him his heart is pumping well. His blood chemistry was also normal and that there really is nothing to worry. Then I proceeded to explain what happened to him after his exercise.

He has a low sugar level to begin with. His FBS was 86, very normal yet for someone with this level, waking up after an 8-hour sleep with no food and immediately jumping into the treadmill is really risky. During a strenuous exercise, our bodies use a lot of glucose and oxygen to supply the muscle proper energy for it to contract and move. During sleep we also use up some glucose and oxygen especially during our REM cycles. If this patient has 86 as baseline sugar, used it up during his sleep, then probably he had a very low sugar when he started his exercise. So much so that an hour and a half of treadmill exercise with weights was enough to push his sugar down to very low levels. When his sugar was low, it was the time he felt weak and started to have cold sweats then thereafter, he lost his consciousness. A case we call hypoglycaemia.

He beamed with a smile when he heard this and said that nobody explained these things to him. He said if there was one thing he learned that day, it is that he should not go into strenuous exercise without proper advice from a doctor.

I ended with giving him an exercise prescription. To compute for the heart rate appropriate for him during exercise, I took the target heart rate first which is 220 – age. The result is multiplied with his percent activity. Percentage is based on his daily activity status. For patients with sedentary lifestyle, THR is multiplied by 60-70%, moderate physical activity is 80-90% while athletes can be computed up to 100%. With him I started with a 70-80% physical activity with the intention of increasing it every month. I told him that he should exercise at this heart rate: 126-144 beats per minute. Less than that his exercise is useless, more than that he’s going to tire himself and risk having hypoglycaemic attacks. I also strongly recommend that he exercise for 20-30 minutes per day, starting with a 5-minute work-up, a 15-20 minutes intensive exercise and a 5-minute cool down.

He left my clinic with this question: “ Can you take care of my health from now on Dra?”. I smiled and said “Yes, of course.”