What should my correct marathon race weight be?
Formula to determine the correct race weight
Being the right race weight is important. Too heavy and you’ll be carrying unwanted pounds. Too light and you won’t have the reserves to last the distance. Eating the right things and taking in the right amount of calories is important but can easily be worked out with a little effort.
A weight statistician, Dr. Stillman, uses the following formula to determine the average weight of a person living in the Western world. For a man, allocate 110lbs for the first five feet in height then 5.5lbs for every inch thereafter. This would see a 6ft average non-active male weighing 176 lbs (12st 8lbs). For an average non-active woman use 100lbs for the first 5ft in height then 5lbs for every inch thereafter. Runners should come in under these averages and if not, but nevertheless on a good training programme, should examine their dietary intake.
Calories in and calories out is the determining factor. Between 3000 and 4000 calories a day is required to maintain body function. Job or household requirements should be taken into account when using calories as a measure. It is estimated that one hour of moderate running uses about 1000 calories. If 5000 calories a day are going in, then there is likely to be a weight gain and weight for a runner is a handicap.
Eat less fat
It is not eating less but eating non-fat food that is the answer. A gram of carbohydrate or protein produces 4 calories, a gram of fat 9 calories. Butter has 23.4 grams of fat per oz. which equals 210.6 calories. Fat intake restricted to 50 grams a day will see a weight loss as of course, will an increase in running mileage.
It has been estimated that running a marathon in energy terms consumes a day’s total food intake. This deficit will be made up very quickly. Dr George Sheehan has suggested another measure of an ideal weight for an endurance runner. This is to allocate 2lbs for every inch in height. Thus a man 5ft 6ins should weigh 126lbs (9 stone). Formulas such as these should always be seen as guides and not as absolutes. Everyone is different by gender, age, and by experience. The one positive thing is that you do not want to carry any more weight than is necessary when running for 26 miles plus.