Accelerometer-based heart rate adjustment for ambulatory stress research.

Area of Science:

• Physiology
• Psychophysiology
• Biomedical Engineering

Background:

• Heart rate (HR) monitoring for mental stress detection is challenging due to physical activity interference.
• Additional heart rate (aHR) aims to isolate psychosocial stress by correcting HR for hemodynamic and metabolic demands.

Purpose of the Study:

• To evaluate if incorporating posture, activity type, and lagged movement intensity improves aHR estimation.
• To assess aHR's sensitivity to mental stress, posture, and physical activity manipulations in a controlled setting.

Main Methods:

• Utilized accelerometer data to determine movement intensity, posture, and activity type in 197 participants.
• Developed and tested an enhanced aHR model incorporating physical activity predictors.
• Compared aHR performance against observed HR in differentiating stressor types.

Main Results:

• Posture, activity type, and lagged movement intensity significantly improved HR estimation accuracy.
• aHR generally underestimated reactivity but captured individual differences in response to mental stressors.
• aHR demonstrated a limited but superior ability compared to observed HR in differentiating physical versus mental stress.

Conclusions:

• The novel aHR estimation method shows potential for more accurate mental stress assessment in naturalistic environments.
• Future research should validate aHR in daily life and explore its predictive health outcomes.
• Refining aHR may improve the differentiation between physical and mental physiological demands.