The Actiheart is a compact, chest-worn monitoring device that records heart rate, Inter-Beat-Interval (IBI), and physical activity in one combined, light-weight waterproof unit.
It is designed for calculating and measuring Energy Expenditure in free living.
- Record Heart rate and activity for up to 21 days
- Record IBI for up to 440,000 beats (3.5 days @ 76bpm)
- Compact and lightweight: less than 10 grams
- Clips onto two ECG electrodes worn on the chest
- Can also be worn on a belt, similar to a Polar wearlink belt
- Noninvasive technology
- Waterproof design
- Nonvolatile memory
- Available as a paediatric monitor
- The new gold standard for measuring Activity Energy Expenditure: validated against Doubly Labeled Water
How does the Actiheart work?
The Actiheart has two clips which attach directly to standard ECG electrodes. Usually one electrode is adhered at V1 or V2 (4th intercostal) and the second electrode is placed approximately 10cm away on the left side at V4 or V5, although this placement can be adjusted to be comfortable for the subject. The number of R-waves detected is recorded in 15, 30, or 60 second epochs. Simultaneously, an internal accelerometer senses the frequency and intensity of the subject's torso movements.
HRV or IBI data can be logged for up to 440,000 beats. For further information on measuring HRV data with the Actiheart please see the page on Heart Rate Variability.
Energy expenditure is calculated from both the activity and the heart rate data and the total recording time available depends on the options selected (please see the table below for more details). For further details on how the Actiheart calculates energy expenditure, please see the page on calculating Activity Energy Expenditure.
Actiheart Recording Times
The Actiheart is ideal for use in both short and long term monitoring situations. The following table shows the maximum recording times available in different modes:
|Epoch||15 seconds||30 seconds||1 minute|
|Recording time HR+Act||21 days||21 days||21 days|
|Recording time HR+Act +IBI Max-Min||10 days||20 days||21 days|
|IBI recording capacity (Beats)||440,000||N/A||N/A|