Good morning.

I received a couple of questions about some metrics in Tom’s Tracking, so I’ve collated the answers below.


WEIGHT
I am measuring weight first thing in the morning, post urination and prior to consuming any fluids.

When it comes to weight, it doesn’t really matter when you track it, so long as it is consistent. Morning tracking works well for me because it’s easy to remember. 


ENERGY BALANCE
Energy expenditure is measured using my Fitbit. I thought it was a bit generous on the energy expenditure - many fitness trackers are but time will tell. Right now, it seems to be working quite well.

Energy Intake is measured by tracking food intake using Easy Diet Diary. This also provides the macronutrient breakdown. 


THEORETICAL FAT BURNT
This is a number I am playing around with, and have been working at for about a month. 1kg of fat contains 9000 kcal (9kcal/gram). However, the number used for losing 1kg of fat via the diet is 7700 kcal, as there is also water and other structures in 1kg of fat tissue.

However, I have found this underpredicts fat loss, so I am currently trialling 7000kcal. 

Essentially, the theoretical fat burn is the energy balance/7000kcal, which tells how much fat mass has theoretically been burnt. It’s not a perfect metric, but worth testing some more.

I say 'theoretically' because I made it up and am unsure of efficacy, although it looks promising thus far.


SLEEP
The sleep is also tracked by my Fitbit. It tracks REM, deep, and light sleep. It also tracks time awake, although this is not on the spreadsheet.

Apparently, it’s normal to wake up 15-30 times per night, but they are so brief you don’t remember them. I was unaware of this, until I saw the frequency of waking from the sleep tracking.

I know the sleep looks low, but this does not include ~40-50 minutes of awake time that I usually have. Because the Fitbit calculates sleep by heart rate and absence of movement, it takes a while to detect sleep. 

So I'm probably not having the first 20-30minutes of my sleep tracked (before the tracker identifies it). I could set it manually, but I would forget too often, making the reading inconsistent.


BLOOD PRESSURE
I am very interested in tracking blood pressure and it’s response to weight loss and cardiovascular training. It’s an area I have been researching lately, so now I have to test it out.

The morning reading is taken straight after I weigh in. The midday reading is taken around 12:30 pm, when I am sitting down to get back into work. 

I apparently get ‘white coat syndrome’ when my blood pressure is taken, so I figure a few months of twice-daily measurement should inoculate me from that issue.  

Tom Fitzgerald