Heart rate variablility is a measure of the variation in time between each heartbeat. It is a measure of the balance between the sympathetic and parasympathetic nervous systems. The sympathetic nervous system is responsible for the fight or flight response, while the parasympathetic nervous system is responsible for the rest and digest response. A high HRV is associated with a healthy heart and a low HRV is associated with an unhealthy heart, although there is a good bit of nuance to this. Now on the other hand, Guinness, is a beer. As a beer should, it contains alcohol. Alcohol is well-known to completely wreck one's HRV. The most Is this a very thin basis on which to base a trial on? Absolutely. Is this just an excuse to drink a large amount of random Guinness on an even larger timeframe? Maybe.

The Statistics

Our dependent variables are

HRV (as measured by my FitBit Inspire 2 via the RMSSD algorithm)

From the different populations

Days where no Guinness has been consumed for at least three days

Days after Guinness consumption