Why your medication may be affecting your workout

 

EXERCISE has become an integral part of daily life for many Malaysians. Whether it is brisk walking, cycling, gym workouts, hiking or pickleball, more people are embracing physical activity as part of a healthier lifestyle.

At the same time, many Malaysians are living with chronic conditions such as hypertension, diabetes, asthma and high cholesterol. For them, daily medication is just as routine as lacing up a pair of running shoes or tracking steps on a fitness watch.

Both exercise and medication play important roles in maintaining health. What is less commonly discussed, however, is how the two can sometimes interact in ways that affect performance, safety and recovery.

As a pharmacology educator at Pusat Kanser Tun Abdullah Ahmad Badawi, Universiti Sains Malaysia, I often ask students a simple question: Is exercise always beneficial for everyone in every situation?

The answer is more complex than a simple yes or no.

Exercise places stress on the body, but it is usually a beneficial form of stress. Heart rate increases, breathing becomes faster, blood vessels expand and muscles require more energy. Over time, the body adapts and becomes stronger and more efficient.

Medication, however, can influence many of these same physiological processes.

For example, individuals taking beta-blockers for hypertension may notice that their heart rate does not rise as easily during exercise.

Even when exerting significant effort, they may struggle to reach the same training intensity they experienced before starting treatment. In many cases, this reflects the intended effect of the medication rather than a decline in fitness.

People with asthma may experience temporary side effects such as shakiness or palpitations after using certain inhalers, particularly during physical activity.

Meanwhile, individuals with diabetes who combine glucose-lowering medication with intense exercise may be at risk of hypoglycaemia, especially if meals, hydration or medication timing are not properly managed.

Symptoms such as dizziness, trembling, confusion or sudden fatigue during exercise should never be ignored. Sometimes the issue is not poor fitness or lack of effort, but the interaction between medication and physical exertion.

This is particularly relevant for patients undergoing rehabilitation programmes, including cancer survivors rebuilding strength after treatment. Exercise remains an important component of recovery, but it must be tailored to each individual’s medical condition, physical limitations and ongoing treatment.

The relationship between exercise and medication is not one-sided. Physical activity can also influence how medications behave within the body.

Changes in blood circulation, metabolism, hydration and body temperature during exercise may affect how certain medications are absorbed, distributed and processed.

Someone taking diuretics, commonly known as water pills, may already be losing significant amounts of fluid through urination.

Combined with prolonged outdoor exercise in Malaysia’s hot and humid climate, this can increase the risk of dehydration, dizziness and fainting.

Similarly, cholesterol-lowering medications such as statins are generally safe and highly effective.

However, some individuals may experience muscle aches or weakness, particularly during intense physical activity. In rare cases, severe muscle injury can occur and may require medical attention.

Modern fitness culture has introduced another layer of complexity through supplements and performance-enhancing products.

Pre-workout drinks, energy chews, fat burners and powdered supplements are widely marketed as part of an active lifestyle. Because many of these products are sold openly, consumers often assume they are harmless.

However, some supplements contain very high levels of caffeine or other stimulants that may interact with prescription medications, particularly those affecting blood pressure and heart function.

Without proper understanding, combining multiple stimulants with existing medication may place unnecessary strain on the cardiovascular system.

None of this means people should avoid exercise because they take medication. On the contrary, regular physical activity remains one of the most effective ways to improve long-term health, reduce disease risk and maintain quality of life.

What it does mean is that exercise should not always be approached with a one-size-fits-all mindset.

Patients should feel comfortable discussing their exercise habits openly with doctors and pharmacists, including the type, frequency and intensity of their workouts.

Likewise, fitness trainers should be aware when clients are managing chronic medical conditions or taking long-term medication, as these factors can influence exercise tolerance, performance and recovery.

Perhaps most importantly, people should learn to listen to their bodies. Feeling challenged during exercise is normal. Persistent chest discomfort, severe dizziness, unusual fatigue, abnormal heart rhythms or sudden weakness are not.

Modern healthcare increasingly recognises that health is shaped by multiple interconnected factors. Sleep, nutrition, stress, medication and physical activity all influence one another in complex ways.

The goal is not simply to exercise harder, but to exercise more wisely. Understanding how your body responds to medication may be just as important as the workout itself.  

Dr Mohd Yusmaidie Aziz is a Senior Lecturer at the Department of Toxicology, Pusat Kanser Tun Abdullah Ahmad Badawi, Universiti Sains Malaysia.

The views expressed are solely of the author and do not necessarily reflect those of  MMKtT,

- Focus Malaysia.