Exercise is Medicine Part 3

Prescribing exercise

Although there are powerful arguments that exercise is medicine, prescribing exercise is very different to prescribing drugs. Drug prescription means:

1. The “patient” has a medical problem which should benefit from medication – or is at risk of such a problem. Guidelines exist to help the prescriber make such decisions.
With exercise there are numerous medical problems which can be prevented and/or treated by exercise. Indeed there are few who do not benefit.

2. A dose can be prescribed which is appropriate for the condition being treated.
With exercise, this cannot be as exact as drug prescription has to be. The Department of Health produces guidelines for exercise prescription – 150 minutes per week of moderate to vigorous exercise with muscle strengthening exercises on two days per week. Unlike drugs, any dose of exercise is beneficial. Underdosing and overdosing do not carry either the loss of effect or a serious risk of side effects.

3. The instructions for taking medication are straightforward and rarely take time to explain.
This is not so with exercise – an effective exercise prescription requires time-consuming discussion of the type of exercise and where to get it, and also the frequency, intensity and duration. Just recommendation increase in physical activity is very unlikely to have much effect.
An exercise prescription should include the following specific recommendations:
Type of exercise or activity (eg, walking, swimming, cycling)
Specific workloads (eg, watts, walking speed)
Duration and frequency of the activity or exercise session
Intensity guidelines – Target heart rate (THR) range and estimated rate of perceived exertion (RPE)
Precautions regarding certain orthopedic (or other) concerns or related comments

4. The effect of the drug can be measured – either in numerical form like weight or blood pressure or from the patient’s symptoms like pain relief or lifting of depression.
If exercise is prescribed for high blood pressure or for depression the outcome can be measured. But one of the most desirably effects of exercise is disease prevention – only measurable from the outcomes for large groups. The ideal measure would be the change in level of physical fitness after a period of exercise. This is not easy and can be expensive.

5. Although compliance can be a problem it can safely be assumed that the “patient” is likely to take the medication.
This is not true of exercise – indeed it is more accurate to assume that this particular medicine is not being taken – and if it is, the “patient’s” word about the degree of compliance is not reliable. Research has found that a doctor’s recommendation to take more exercise has little effect on the patient’s physical activity.