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Daily Nutrition

 

Contents

  • Introduction
  • Balancing calorie intake and expenditure
  • The proportion of Carbohydrate, Fat and Protein in your diet
  • The glycemic index of the foods you consume
  • Are you getting enough vitamins and minerals?
  • Food allergies

Introduction

Due to a decrease in the daily activity of the majority of the population resulting in obesity issues our eating habits have received a lot of bad press.  This has led to a very negative attitude towards eating with an over emphasis on reducing the calorie content of the foods we eat.  As an active triathlete obestiy isn't likely to be a concern and I would encourage you to have a positive attitude towards food as your daily diet can play a significant role in your triathlon performance.  Amongst other things it can:

 

  • Help maintain a healthy immune system and prevent illness
  • Build strong and health bones, muscle and connective tissue helping avoid injury and improve performance
  • Maintain and potentially help build skeletal muscle
  • Influence the way your body responds during exercise
  • Help you recover from exercise sessions

 

Balancing Calorie intake and expenditure

The number of calories you require on a daily basis (daily caloric expenditure) is made up of the following 3 components:
  • Resting Caloric Expenditure (RCE)
  • Daily Activities Caloric Expenditure (DA)
  • Exercise Caloric Expenditure (ECE)
Formula: Daily caloric expenditure = RCE + DA + ECE

Resting Caloric Expenditure - As the name suggests this is the amount of calories you burn in a day whilst doing nothing. You can use formulas to estimate it or measure your bodies oxygen consumption at rest to get a more accurate figure. The figure will be relatively stable over time but is mainly affected by your muscle mass.  Other less significant influences include:
  • Body surface area - estimated by height and weight)
  • Age
  • Temperature - If you are cold you will shiver more to generate heat and burn more calories

Daily Activities Calories - These are the calories you burn from day to day tasks which is very dependant upon what you do for a living.  Someone who sits at a desk all day every day will have a very low figure for DA whilst a builder will have a much higher figure.  This is always going to be an estimate and some common values are given below:

Exercise Caloric Expenditure - These are the calories you burn each day from exercise.  For a triathlete this will be the area that varies most on a day to day basis.  During a heavy training phase or whilst racing this value can be very high whilst on a rest day it will be zero. Like your daily activity calories this will always be an estimate, but as you are likely to be wearing a training devices during many of your exercise sessions these can help to make the estimations more accurate.