# Sit-to-stand and stand-to-sit transitions stimulate cardiac autonomic regulation and lead to age-dependent short-term patterns in heart rate

## TL;DR

Standing up and sitting down briefly stimulate heart regulation, with effects that change with age.

## Contribution

The study identifies reproducible heart rate patterns during sit-to-stand and stand-to-sit transitions and shows age-related changes in these patterns.

## Key findings

- Standing up and sitting down cause reproducible heart rate transitions within 30 seconds.
- Heart rate patterns show age-related delays in reaching local minima and reduced HRmin/HRmax ratios with increasing age.

## Abstract

Sedentary behaviors pose health risks, which can be mitigated by regular exercise. The impact of everyday movements on cardiac autonomic regulation is not well-established. The present study investigated whether standing up and sitting down from a chair leads to a reproducible transition pattern in heart rate. Furthermore, age-related changes in this pattern were assessed.

Forty healthy participants (18–65 years, 22 female) performed eight repetitions of standing up from a chair and sitting down. Electrocardiogram and accelerometer data were recorded throughout the procedure. The average RR interval series was used to quantify the transition pattern evoked by the movement.

Both movements resulted in a transition pattern in the RR interval and corresponding heart rate (HR) series within 30 s. After the initiation of movement, a local maximum HR appeared at a median of 8.1 s (standing up, HRstand max = 78.4 bpm vs. HRsit = 62.4 bpm) and 2.1 s (sitting down, HRsit max = 78.0 bpm vs. HRstand = 70.2 bpm), followed by a local minimum HR at a median of 18.0 s (standing up, HRstand min = 68.0 bpm; p < 0.001 vs. HRstand max and HRsit) and 14.1 s (sitting down, HRsit-min = 60.7 bpm; p < 0.001 vs. HRsit max and HRstand). Subsequently, the HR increased until a steady state was reached. The time to reach the local minimum increased with age for both movements. Furthermore, the standing up HRmin/HRmax decreased with increasing age.

Standing up from a chair and sitting down each briefly stimulate cardiac autonomic regulation. The transition process partially slows down and becomes less pronounced with increasing age. Increasing the daily amount of standing up contributes to cardiac autonomic regulation flexibility and helps mitigating cardiovascular risks from sedentary behaviors.

https://drks.de, Unique identifier: DRKS00021712.