Tri Talk Nutrition Calculator
beta version 0.8
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The Tri Talk Nutrition Calculator (TTNC) is designed to give athletes a baseline strategy for race-day nutrition. While nothing replaces race nutrition simulation while training, or pure years of experience, the intent of the TTNC is to give the athlete a starting point to begin experimenting with different caloric intake amounts. Thereby reducing the number of errors in the unavoidable trial and error process of nutrition strategies. The calculator uses fitness, intensity, distance, weight, and use of fat vs. glycogen to calculate an approximate amount of total calories required for the event.
Please note that every athlete's stomach can tolerate a diverse amount of calories per hour. Also, it has been noted by several listeners that many theories hold that the human body can only absorb (oxidize) up to 360 calories per hour. However, current research indicates that the type of carbohydrate consumed can increase this oxidation by and absorbtion to over 500 calories per hour. This is discussed in Tri Talk Episode 49.
A detailed discussion on the theory behind the Tri Talk Nutrition Calculator can be heard in Tri Talk Episode 45. I very much would like to hear your feedback on the TTNC to improve the formulas.
				= Input required
				= Automatic calculation based on input
Enter your weight in pounds				pounds
Select your estimated fitness level		High Medium Low
High < 12% body fat
Medium > 12% <20%
Low >20%
Females add 6% to guidelines
Total estimated glycogen stores:				calories
Override estimate (optional)
Select event type		Sprint Olympic Marathon Half Ironman Ironman
Enter estimated race intensity				%
As % of Max Heart Rate
Zone 2 (Ironman) 75-82%
Zone 3 (Half-Ironman, Marathon) 82-87%
Zone 4 (Sprint, Olympic) 87-90%
Zone 5 (Sprint) 90%+
Estimated race intensity as % of VO2max				%
		Actual			Suggested
		Minutes		Hours	Minutes		Hours
Swim Time
Bike Time
Run Time
Total Time
		Actual		Suggested
Swim calories burned
Bike calories burned
Run calories burned
		Please ensure you adjust your actual calories burned above!
Estimated total calories burned
Estimated % of calories burned from fat
Required calories from glycogen
Add some calorie "insurance"
Total calories required
Total calories required minus initial glycogen stores
Hours on bike and run
Required Calories per hour
Formulas used in the Tri Talk Nutrition Calculator
		Formula		Where…
Base calculation	=	C(h)=(G-(EE(R)+I))/Dh		C(h) =	Calories per hour
				G =	Initial glycogen levels
				EE =	Energy expenditure
				R =	Fat to carbohydrate ratio
				I =	Calorie "insurance"
				Dh =	Event duration in hours
Estimated glycogen stores	=	W(FR)		W =	Weight
				FR =	Fitness level ratio
				High =
				Medium =
				Low =
Estimated race intensity as % of VO2max	=	(%MHR-37)/0.64		%MHR =	% of Max Heart Rate
Baseline race time performance, medium fitness	=		Minutes				Total Minutes
			Swim	Bike	Run	Total Hours
		Half Ironman	39	180	105
		Ironman	78	360	240
		Marathon	0	0	210
		Olympic	30	68	45
		Sprint	15	34	21
Baseline race time performance fitness multiplier	=	BL(FR)		BL =	Baseline medium fitness performance
				FR =	Fitness level ratio
				High =	0.90
				Medium =	1.00
				Low =	1.15
Estimated total calories burned	=	(W/SM)(ST/60)(IM)(%VO2)		W =	Weight
		+		(S,B,R)M =	Swim, Bike, or Run multiplier
		(W/SM)(ST/60)(IM)(%VO2)		Swim =
		+		Bike =
		(W/RM)(RT/60)(IM)(%VO2)		Run =
				(S,B,R)T =	Swim, Bike, or Run time
				IM =	Intensity multiplier
				Multiplier =
				%VO2 =	Intensity as a % of VO2max
Estimated % of calories burned from fat	=	(1-(%VO2/100))(FR)+.03		%VO2 =	Intensity as a % of VO2max
				FR =	Fitness level ratio
				High =
				Medium =	1.00
				Low =	1.05