Cardiovascular health is not a single number. It is a set of related signals — some reflecting how your heart and blood vessels work day to day, others capturing long-term structural change, and others describing your body's capacity to use oxygen during effort. Intentra groups these under Cardiovascular Health and Cardio-respiratory Fitness because they answer different questions. Understanding what each metric actually measures makes the data useful rather than overwhelming.
The two lenses: structure and function
A useful mental model is to separate structural indicators from functional ones.
Structural indicators describe what has accumulated in the cardiovascular system over years — calcified plaque in the coronary arteries, for example. These change slowly and are measured infrequently.
Functional indicators describe how the system is performing now — blood pressure at rest, aerobic capacity, resting heart rate, and how quickly heart rate falls after exercise. These can move meaningfully within weeks or months in response to training, sleep, stress, illness, or medication.
Neither lens is complete on its own. A person with excellent fitness can still have elevated blood pressure. A normal blood pressure reading does not tell you whether plaque is present in the arteries. Intentra presents both lenses so you can see the full picture over time, not infer everything from one metric.
Blood pressure: pressure in the pipes
Blood pressure — systolic over diastolic, in mmHg — reflects the force of blood against arterial walls as the heart beats and rests between beats. It responds within minutes to posture, caffeine, stress, recent activity, and measurement technique.
Because of that variability, a single reading is a sample from a wide distribution, not a fixed truth about your cardiovascular health. What matters is the pattern across consistent measurements taken under similar conditions: same time of day, seated, rested for several minutes, cuff at heart level.
Intentra's blood pressure view is built around that trend logic. Gradual movement in your average readings over months is more informative than any one number crossing a threshold on a given morning.
Coronary artery calcium: structural plaque
A CAC (coronary artery calcium) score comes from a specialist CT scan. It detects calcified plaque in the coronary arteries and expresses the result as an Agatston score. A score of 0 means no calcified plaque was detected at the time of the scan — a meaningful data point, especially for people at intermediate risk based on age and cholesterol alone.
CAC is not a daily metric. Most people will log one scan every few years. Its value in Intentra is as long-term context: a record you can bring to clinical appointments and read alongside blood pressure and fitness trends. It does not capture non-calcified plaque, and it does not replace clinical risk assessment — but it answers a question blood tests cannot: whether calcified atherosclerosis is present in the coronary arteries right now.
VO₂ max: aerobic capacity
VO₂ max describes the maximum rate at which your body can use oxygen during intense effort, usually expressed in millilitres per kilogram of body weight per minute (mL/kg/min). Among the metrics available outside a hospital setting, it is one of the strongest predictors of long-term cardiovascular health in the general population.
Wearable estimates are derived from outdoor cardio activity — typically running or cycling — and are useful for tracking your own trend rather than benchmarking against a population table. Lab tests from a cardiopulmonary exercise test (CPET) are more precise and capture additional detail (max heart rate, test type, body mass at test), but occur far less often.
Intentra shows both sources on the same trend chart because the question that matters is whether aerobic capacity is moving in a direction consistent with your training and recovery — not whether today's estimate is exactly 44.8 or 45.1.
Resting heart rate and heart rate recovery
Resting heart rate — the number of beats per minute when you are calm and inactive — is one of the most reliable metrics consumer wearables measure. Over weeks and months, a gradual decline often accompanies improved cardiovascular fitness. A sustained elevation above your personal baseline can reflect accumulated fatigue, illness, poor sleep, or stress.
Heart rate recovery — how much your heart rate drops in the first minute after exercise — reflects autonomic nervous system function. Higher recovery (a larger drop) generally indicates a stronger parasympathetic response. Like VO₂ max, it responds to consistent training over time.
These sit alongside VO₂ max in Intentra's Cardio-respiratory Fitness screen as related signals: simpler markers that add context to the aerobic capacity picture without requiring a separate interpretation framework for each.
How to read them together
None of these metrics should be treated as a verdict. They are inputs that become meaningful in combination and over time:
- Blood pressure trending up alongside poor sleep and elevated resting heart rate suggests a pattern worth attention — not necessarily pathology, but a signal to review lifestyle factors and discuss with a clinician if sustained.
- Stable or improving VO₂ max with a gradually lower resting heart rate suggests training is producing the expected cardiovascular adaptation.
- A CAC score above zero does not negate good fitness or normal blood pressure — it adds structural information that may change clinical management. A score of zero does not guarantee arteries are entirely clear, but it is a genuinely useful negative finding.
Intentra's role is to organise these signals, show trends rather than flag individual readings, and keep structural and functional data in one place. It does not diagnose, prescribe, or replace the judgement of a qualified health professional.
If any cardiovascular metric concerns you, or you experience symptoms such as chest discomfort, unusual breathlessness, persistent headaches, or visual changes, seek medical advice rather than relying on self-monitoring alone.