Your Daily Energy Requirements

Just a quick run today, 5Km in 25:08, a slow warm up then fartlek for the last 4Kms.

Yesterday I mentioned a way of determining your daily energy requirements, so after a eye blurring hour or so writing the HTML for the tables here it is. First of all I will credit it, this came from The Complete Guide to Food for Sports Performance by Dr Louise Burke, the tables all came from Recommended Nutrient Intakes, NHMRC, Australia 1990.

Step 1 - Determine your Base Metabolic Rate. Your base metabolic rate is the minimum number of Kilojoules required every day to keep you alive, this is based on your gender, age and weight

Gender	Body Weight	10-18 yrs	18-30 yrs	30-60 yrs	over 60 yrs
Male	55 Kg	6824	6360	6295	5156
	60 Kg	7195	6675	6535	5400
	65 Kg	7565	6990	6775	5645
	70 Kg	7935	7305	7015	5890
	75 Kg	8305	7620	7255	6135
	80 Kg	8675	7935	7495	6380
	85 Kg	9045	8250	7735	6625
	90 Kg	9415	8565	7975	6870
Female	40 Kg	5140	4515	4900	4275
	45 Kg	5420	4825	5070	4465
	50 Kg	5700	5135	5240	4845
	55 Kg	5980	5445	5410	5035
	60 Kg	6260	5755	5580	5225
	65 Kg	6540	6065	5750	5415
	70 Kg	6820	6375	5920	5605
	75 Kg	7100	6685	6090	5795

Step 2 - Rate your everyday activity level, minus your sporting activity. Bear in mind that if you have an office job and spend alot of the day on your butt on front of a computer (like I do) then your acitvity level will probably rate as Light. If you have a physical job, for example you are a builder or landscape gardener then you will rate higher. Once you have selected your everyday activity level (minus sporting activity) multiply by your Base Metabolic Rate

Activity	Males	Females
Bed Rest	1.2	1.2
Very Sedentary	1.3	1.3
Sedentary	1.4	1.4
Light	1.5	1.5
Light/Moderate	1.7	1.6
Moderate	1.8	1.7
Heavy	2.1	1.8
Very Heavy	2.3	2.0

Step 3 - Estimate the average cost of your training. Multiply the hours you spend in exercise every week by the energy cost of the specific task. The energy cost is given as Kj per minute, therefore if you ran for an hour at 5.5 min/km and you weigh 60Kg then the energy cost is 2940 Kj. When you have the weekly figure divide by 7 to get your daily everage.

Speed	50 Kg	60 Kg	70 Kg	80 Kg	90 Kg
5.5 min per Km	40	49	57	65	73
5 min per Km	44	52	61	70	78
4.5 min per Km	48	55	65	75	85
4 min per Km	54	65	76	87	98

Step 4 - There are allowances for kids under 18 and breastfeeding and pregnant woman but I haven't put these in, if you are interested post a comment and I'll add them.

Step 5 - Add it all together and you have your daily energy requirements. If you would like to lose weight then aim to reduce this figure by about 2000 Kj per day.

So an example, I am a 32 year old female who weighs 58 Kg and runs on average 6.5 hours a week betwen 5:00 and 5.5 minute Kms (so I will calculate on 5.5 minutes Kms) and I have an office Job

BMR = 5755
Actvity Level Light = 1.5
Energy Cost over 7 days = 19110
Average per day = 2730

Daily energy requirements (approx) = 5755 X 1.5 + 2730 +11362

So 11362 Kjs per day to maintian my body weight. Though for me this will be less as I based mine on 60Kg and I weigh 58 kg, so in reality it is more likely to be 10500. This is more generous than I would have thought, but I have to consider I am running between 70 and 80 Kms per week.

I apologise that the Male weight only goes up to 90 Kg and the Female only goes up to 75 Kg, the book didn't give data for weights over this range.

Obvioulsy this is just a guide as well but if you are eating proper meals and looking after yourself you should have a pretty healthy metabolism so the figures should be reasonably accurate.

Have fun, hopefully like me you will find out you can eat more than you thought :-)