Sleep score: 2 whiskeys and nachos before bed

Last night I (Ben) had two whiskeys and a plate of nachos before bed. Thankfully my sacrifice makes for a great example of what this does to your sleep. Below you will see side by side comparisons of a night of sleep that was good vs. last night (good on left, last night on right):

Feedback:

• Resting heart rate is 8 BPM higher. It is very difficult to get as much deep sleep if you have a higher than normal resting heart rate. 8 BPM is the average increase I experience from moderate alcohol consumption.

• Heart rate variability score was down by half, that’s bad. With HRV the comparison is mostly relevant against yourself and the trend is what matters. Higher HRV is associated with good rest and recovery (being energetic the next day). Low HRV is associated with fight-or-flight, stress, eating before bed, and obviously alcohol. I wasn’t stressed so the deterioration is due strictly to the alcohol and nachos.

• Ideally your body temperature should drop.

• Recovery index is how long it takes for your heart to reach it’s lowest BPM, this is highly correlated to feeling rested the next day and getting enough deep sleep.

Now let’s look at REM and Deep sleep:

Feedback:

• The REM is very close across the two evenings, but the Deep sleep was nuked by more than half. I have noticed that my endurance (e.g. playing tennis) is more closely correlated to length of deep sleep than anything else.

• Also, note that the Deep sleep was 25% of total sleep, vs. just 8% after the two whiskeys. I got a full hour MORE sleep, it just wasn’t of a high quality. Absolutely terrible.

• Note the latency - if you fall asleep in 3 minutes that’s usually a bad sign.

Now let’s look at heart rate:

Feedback:

• There are three interesting things to point out here:

  1. The range of heart rate from peak to trough increased from [58-75] to [66-85].

  2. Average heart rate was 11 points higher, and lowest resting heart rate was 8 points higher.

  3. Note how in the first graph the heart rate declines and then stays low throughout the night, while in the second graph it takes literally all night for it to reach its lowest point. This is terrible for recovery and feeling energetic the next day.

Lastly, let’s look at heart rate variability (HRV):

Feedback:

• Your HRV is highly correlated with energy levels the following day. Higher is better, and the main metric against which you are measuring it is your past self.

• Note how variable the fluctuations are during the good night sleep, and how long it took for there to be any noticeable variations at all during the bad night sleep.

Moral of the story, don’t drink whiskey and eat nachos before bed on a regular basis!