Cardiac Workload
Cardiac Workload (Rate Pressure Product or RPP) estimates how hard your heart is working to pump blood. It is calculated by multiplying your heart rate by your systolic blood pressure. A lower number means your heart is working more efficiently at rest — like a fuel-efficient engine idling smoothly. A high resting workload means the heart is under strain even when you're not exercising.
Normal range
How Vsense measures it
Vsense computes Cardiac Workload by combining the estimated heart rate and systolic blood pressure signals from the facial scan. The result is divided by 1,000 for readability.
How it's scored
Below 10: Efficient — heart is working comfortably at rest. 10–15: Moderate strain — investigate contributing factors. Above 15: Elevated workload — indicates high heart rate, high blood pressure, or both, putting the heart under significant effort.
What a high reading means
Elevated cardiac workload means your heart is working harder than it should at rest — often due to high blood pressure, rapid heart rate, or both. Sustained high workload is associated with increased myocardial oxygen demand, which matters in people with existing coronary artery disease. Long-term, chronically elevated workload contributes to heart muscle strain and cardiovascular disease.
What a low reading means
Low cardiac workload is excellent. It means your heart is pumping efficiently — a sign of good cardiovascular fitness, controlled blood pressure, and a calm resting heart rate. Well-conditioned athletes typically have the lowest cardiac workloads at rest.
How to improve it
Exercise
- Regular aerobic exercise is the most powerful way to reduce resting cardiac workload — it lowers both heart rate and blood pressure simultaneously
- Zone 2 training (conversational pace cardio) for 150+ min/week is the gold standard for improving cardiac efficiency
- Even brisk walking 30 min/day reduces resting cardiac workload within 4–8 weeks
- Avoid isometric holds (like prolonged planks or static weight holds) if workload is already high — they spike blood pressure temporarily
Diet
- Reduce sodium to lower systolic blood pressure — the DASH diet reduces BP by 8–11 mmHg
- Limit caffeine — it raises both heart rate and blood pressure, directly increasing cardiac workload
- Stay hydrated — dehydration raises heart rate and blood viscosity, increasing workload
- Beetroot juice, hibiscus tea, and omega-3 fatty acids all have clinical evidence for lowering systolic blood pressure
Lifestyle
- Prioritise blood pressure control — a 5 mmHg drop in systolic BP reduces cardiac workload meaningfully
- Manage stress — anxiety and chronic stress raise both heart rate and blood pressure, the two inputs to workload
- Avoid scanning right after caffeine, exercise, or emotional stress — these temporarily inflate the reading
- Maintain healthy weight — even 5 kg of weight loss reduces blood pressure and heart rate at rest
Natural remedies
- Slow breathing (5–6 breaths/min) for 10 minutes acutely lowers blood pressure by 5–10 mmHg
- Magnesium supplementation (300–400mg/day) has moderate evidence for lowering blood pressure
- L-citrulline (found in watermelon) improves nitric oxide production and vascular relaxation
- Coenzyme Q10 (100–300mg/day) improves cardiac efficiency and has mild blood pressure-lowering effects
Frequently asked questions
What is a normal cardiac workload?
Below 10 is considered efficient for resting conditions. Athletes often have workloads of 6–8. Values above 12 at rest suggest the heart is working harder than needed — usually from elevated blood pressure, fast resting heart rate, or both.
Why does cardiac workload matter?
Cardiac workload determines how much oxygen the heart muscle itself needs. A chronically high workload means the heart muscle is under constant demand, which over time contributes to hypertrophy (thickening), reduced efficiency, and increased cardiovascular risk.
How does stress affect cardiac workload?
Acute stress raises both heart rate and blood pressure within seconds — directly multiplying the cardiac workload. This is why stress management is fundamental to heart health, not just a lifestyle nicety.
Can fitness lower cardiac workload?
Yes, dramatically. A well-trained aerobic athlete's heart at rest beats at 50 bpm vs 70–80 bpm in sedentary individuals, with comparable blood pressure — yielding a cardiac workload roughly 30–40% lower at rest.
