Fig. 2From: Exposure to air pollution near a steel plant is associated with reduced heart rate variability: a randomised crossover studyLow Frequency Power was significantly reduced at the Plant site. Data are expressed as the mean of responses measured from the afternoon ambulatory ECG recording time point. Error bars represent the 5 and 95% confidence limits. Mixed effects linear regression determined that LF power was significantly reduced (* = p < 0.05) at the college site when compared to the plant site, while HF power and the LF/HF ratio did not differ significantlyBack to article page