Saturday, January 7, 2012


strawberryWe all know we need to eat ‘Healthy’ foods and it seems like we are expected to intuitively just ‘KNOW’ what is healthy.  For some of us, and honestly, I think most of us, we’ve been raised in a society with a very skewed version of healthy.  We have fast food outlets and convenience foods telling us everyday what is healthy about them.. coco pops have fibre so they are healthy!

I have decided to start from the beginning.  I know that I didn’t eat well as a child, not too bad and probably better then a lot of people, but mum was a working mum and living in town meant easy access to the lolly shop and convenience foods.  Often money was an issue as well so cheap came ahead of nutritious.  Back to basics though.. I am starting at the very beginning and working out just how many calories I need and what ratio of macronutrients I need.  From there, the healthy part will be about choosing fresh food as close to nature as possible!

Lets begin with the calorie decision.. We know that the minimum we should drop our calories to is 1200 for women.  Below that and you risk upsetting your biochemical homeostasis and triggering the ‘fat saving’ genes into play.  Not a good thing long term.  You might lose weight, but it will be muscle mass – and this will reduce the amount of calories you need and increase the amount sent into storage!  When you  hit your goal, you will have to eat less to maintain.  What we want is to turn our bodies into a metobolic machine that burns calories so we can eat a full and healthy diet with a few slip ups here and there as well (we are human afterall!).

So lets start.. I will take you through my calculations, but you can easily substitute your numbers to work it out for yourself!  Basically what I am doing is working out my maintenance calories and dropping them by 15-20%.  The maximum deficit for calories from food in any one day is 1000cals. This is a pretty safe method to allow for fat loss without the loss of lean muscle mass.

We start with Basal Metabolic Rate – this is how many calories our body needs to just ‘survive’ the day.  There are two main methods.  One just uses your overall weight (what you get when you use an online calculator), the other, your lean body mass (so you need body fat scales).

Harris-Benedict Formula: constant + weight factor + height factor – age factor

Men: 66 + (13.7 x kg) + (5 x cm) – (6.8 x yrs)

Women: 655+ (9.6 x kg) + (1.8 x cm) – (4.7 x yrs)

So for me that’s 655 + 547.2 + 279 – 173.9 = 1307.3 (1220.9 at goal weight)

Katch- McArdle Method

370 + (21.6 x kg) using lean body mass.

Lean body mass can be taken directly from body composition scales are worked out from body fat % and your weight.

For me.. 1265

These are very consistent for me, but if you are not average and have a greater lean body mass, the later will work better for you.

I’m going to use the 1265 number as it is more accurate in general.

The BMR we just calculated does not take into account our activity levels, but I want to calculate my TDEE (Total Daily Energy Expenditure).   I am going to two calculations based on no exercise and moderate exercise.  This is because I calculate my exercise calories using a HRM so by taking the ‘no exercise’ number as my base, I can add on my exercise and be able to get a more accurate figure.  The moderate exercise number will give me a base for my meal plan and my average target.

Activity Factors:

  • x1.2 no exercise
  • x 1.375 for light exercise (1-2 days a week)
  • x 1.55 moderate exercise (3-5 days a week)
  • x 1.725 for heavy exercise (6-7 days a week)
  • x 1.9 for athletes (more then once a day training)

1518 for no exercise

1960 - 2182 for moderate to heavy exercise

Wow, no wonder I have been gaining weight over Christmas!  It looks like if I want to eat ‘normally.. I need to be a heavy exerciser!  Ahhh!

So what do I now know?  I know that if I sick or can’t exercise, 1500 is my maintenance.  If I am doing my exercise then I can creep it up to 2000 a day.  Realistically, somewhere in the middle is probably my maintenance goal.. around 1800 calories a day.

But what about losing weight?

I am going to use my ‘no exercise’ number so I can add on my exercise calories as I burn them.  And I am using the 15-20% guide.  This gives me a range of about:

 1220-1290 cals as my goal for losing weight without exercise, or

1550-1650 cals as my goal for losing weight with moderate exercise.

From that information I will now set my meal plan goal calorie level to 1500, knowing that if I don’t exercise I need to drop that to 1200-1300.


I will work out Macronutrient ratios on another day!

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