My sister-in-law is a doctor and follows my Heart Rate Variability (HRV) adventures. She suggested that I look at my glucose levels and see how it effects HRV. My first step was to buy a glucose monitor and I was somewhat uncomfortable with the idea of drawing blood daily. A trip to Target to buy an Onsync glucose meter was pretty easy and the blood drawing process is far less uncomfortable than I thought it was.
So I started pulling my glucose each morning when I got up. Immediately afterward I took my HRV focussing on rMSSD using the Polar H7 and Heart Rate Variability Logger. I took a reading for 1:30 with three 30 second readings which I averaged out for the session. While taking the reading I used the Paced Breathing Android App. After I was completed I entered the glucose reading and rMSSD in an excel spreadsheet.
Here is what I found. Glucose levels have a strong negative correlation (Pearson value of -0.4) with HRV. That means higher blood glucose had a strong relationship with lowered HRV. That means eat food that jacks your blood sugar and your are less responsive to your environment. Eat candy and be dumber when talking to your boss.
Here is a graph of eight readings:
Looking at the figures you can see that generally my glucose level averaged about 104. When I fasted (12 hours of no food) it dropped below 100. The rMSSD was between 55 and 78, all well above the stress line. So my morning readings showed no stress and normal blood sugars. What it also showed was a strong correlation. So measuring before and after daily events will give more information to see if I really am dumber talking to the boss after eating candy.