Why Physical Therapists Should Measure Walking Speed for Heart Health

Introduction

As a physical therapist, you know the importance of evaluating patients' mobility and functional abilities. A person’s walking speed, or gait speed, is often overlooked when assessing their overall health. However, research increasingly shows that walking speed can be a significant indicator of cardiovascular health and risk. The simplicity of gait speed as a measure makes it an accessible and non-invasive tool, which could be crucial in predicting heart-related issues, especially in older adults and individuals with pre-existing conditions.

In this article, we will explore the connection between walking speed and heart health, examining the science behind gait speed as a diagnostic measure, how it correlates with cardiovascular conditions, and why it should be part of your clinical evaluation toolkit. We will also look at how walking speed can be used to assess cardiovascular risk and the benefits of incorporating gait speed assessments into routine patient evaluations.

The Science of Walking Speed

Walking speed is not just about how fast someone moves. It reflects a complex interaction between various physiological systems, including the cardiovascular, respiratory, musculoskeletal, and nervous systems. From an energy expenditure perspective, efficient walking requires the heart and lungs to work in coordination to supply oxygen to muscles, while nerves send signals that maintain balance and movement. A decline in any of these systems—especially the cardiovascular system—can result in slower walking speeds.

Cardiovascular Efficiency and Gait Speed

Heart function plays a critical role in maintaining a healthy walking speed. The heart pumps blood throughout the body, delivering oxygen to tissues and organs. When the heart isn’t functioning properly—whether due to coronary artery disease, heart failure, or other cardiac conditions—oxygen delivery to muscles is compromised, which affects the ability to walk at a regular pace. As a result, a person with a weakened heart is likely to experience reduced gait speed, fatigue, and even shortness of breath during routine activities like walking.

A study published in JAMA Cardiology found that slower walking speeds were associated with an increased risk of heart disease, hospitalization, and even death in older adults. The researchers concluded that walking speed could serve as an essential early warning sign of declining cardiovascular health, especially in those without overt symptoms of heart disease.

Walking Speed as a Predictor of Cardiovascular Risk

The Link Between Slow Gait and heart disease

For physical therapists, the implications of gait speed assessments are profound. Studies have demonstrated that walking speed is a reliable predictor of cardiovascular disease (CVD) outcomes. For example, a research study in The European Heart Journal found that individuals who walked slower than 0.8 meters per second were more likely to experience cardiovascular events, such as myocardial infarction or stroke, within the next 10 years compared to those with normal walking speeds.

Moreover, individuals with heart failure tend to exhibit slower gait speeds. Since the heart cannot pump blood as efficiently as it should, their muscles don’t receive adequate oxygen during activity, leading to fatigue, muscle weakness, and decreased endurance. This is reflected in the slowing of their walking speed over time.

Gait Speed and Mortality Rates

Interestingly, walking speed has been linked to mortality rates. A meta-analysis in The British Medical Journal reviewed 9 studies involving over 34,000 people and found that faster walking speeds were associated with lower mortality rates. In particular, the researchers noted that for every 0.1-meter-per-second increase in walking speed, there was a 12% reduction in mortality risk. In contrast, slower walkers had a higher likelihood of dying from cardiovascular events, infections, and even cancer.

Gait Speed as an Indicator of Frailty and Cardiovascular Risk

Walking speed is a hallmark measure in the assessment of frailty, especially in elderly populations. Frailty is a condition characterized by reduced physiological reserves and increased vulnerability to stressors like illness or injury. Slow gait speed, typically under 0.6 meters per second, is one of the key diagnostic criteria for frailty. Given that frailty and cardiovascular disease share common risk factors—such as inflammation, oxidative stress, and metabolic dysregulation—individuals who exhibit both frailty and slow walking speed are at particularly high risk for heart-related complications.

Assessing Gait Speed in Clinical Practice

For physical therapists, measuring walking speed is simple, cost-effective, and informative. Here's a step-by-step guide for incorporating gait speed assessments into your practice:

Step 1: Set Up the Walking Path

Choose a flat, straight surface of about 4-6 meters in length. Mark the start and finish lines clearly. This distance ensures that patients reach a steady pace, offering an accurate assessment of their natural walking speed.

Step 2: Instruct the Patient

Instruct your patient to walk at their normal, comfortable pace. Avoid encouraging them to rush, as this will skew the results. If your patient uses a walking aid, allow them to use it during the assessment.

Step 3: Measure the Time

Use a stopwatch to record the time it takes for your patient to walk the designated distance. Start the stopwatch as soon as the patient begins walking and stop it once they cross the finish line.

Step 4: Calculate Walking Speed

Walking speed is calculated by dividing the distance (in meters) by the time (in seconds). The result will give you a figure in meters per second (m/s).

Step 5: Interpret the Results

• A walking speed of 0.8 meters per second or slower indicates a risk of cardiovascular complications.
• A walking speed of 1.0 to 1.2 meters per second is considered normal.
• A walking speed of 1.3 meters per second or faster is associated with good cardiovascular health and reduced mortality risk.

For patients with slower walking speeds, consider referring them for further cardiovascular assessments or to a cardiologist for an in-depth evaluation.

Walking Speed as a Therapeutic Goal

Walking speed is not only a diagnostic tool but can also be used as a target for intervention. Cardiovascular health can improve with targeted rehabilitation programs that incorporate aerobic exercise, strength training, and endurance activities, all of which are designed to increase walking speed.

For patients recovering from cardiac events or surgery, improving walking speed should be a primary therapeutic goal. A multidisciplinary approach, including exercise physiologists, physical therapists, and cardiologists, can be instrumental in guiding patients toward regaining functional mobility and cardiovascular health.

Other Factors Affecting Walking Speed

It’s important to note that walking speed can also be influenced by factors unrelated to cardiovascular health. These include:

• Musculoskeletal issues: Osteoarthritis, hip fractures, and other joint problems can reduce walking speed.
• Neurological conditions: Diseases such as Parkinson’s and multiple sclerosis can affect gait.
• Obesity: Excess weight can limit mobility, impacting walking speed and contributing to cardiovascular strain.

While these factors may confound the relationship between walking speed and heart health, the overall trend remains clear: a decline in walking speed is often a signal that warrants closer examination.

The Role of Walking Speed in Preventative Care

For healthcare professionals, walking speed offers a unique opportunity to intervene before cardiovascular disease becomes symptomatic. For patients, particularly older adults, a reduction in walking speed might not be recognized as a warning sign until more severe symptoms, such as chest pain or shortness of breath, develop.

By assessing walking speed during routine check-ups, physical therapists can identify at-risk individuals early, provide appropriate interventions, and potentially reduce the risk of future cardiovascular events. Regularly measuring gait speed in combination with other assessments, such as heart rate and blood pressure, can create a comprehensive picture of a patient’s cardiovascular health.

Conclusion

Walking speed is more than just a measure of mobility; it’s an accessible, non-invasive indicator of cardiovascular health. As a physical therapist, you are in a unique position to use this simple tool to assess the heart health of your patients, especially those who are older or at risk of cardiovascular diseases. By regularly incorporating gait speed assessments into your practice, you can help detect cardiovascular issues early and guide patients toward appropriate interventions to improve both their heart health and overall quality of life.