Are you asking how I can be so certain that my numbers are realistic, and that I may seem presumptous?
Or are you asking me the best way for somebody to lose that amount of bodyfat?
I think you are asking me the former. I used a very simple observation to presume this statement.
Linford Christie: 4.5 % bodyfat.
Ian Mackie: 4.5%
Carl lewis: Bodyfat went from just unde 6% to 4%, I even heard 3.5% during his career.
There have been many world class sprinters who have had there bodyfat % measured and I have never heard of one that was higher than 6%. More often, they are below 5%.
Look at all the best sprinters, and they are all as lean as the above mentioned sprinters. It is a simple way of coming to the conclusion that 6% bodyfat or below is one of the requirements for world class sprinting.
In my book, a sub 6.6 second 60 meters - on an indoor track (say 6.67 secs) is 0.12 - 0.15 secs slower than being able to win a national final at British championships. A 6.67 would get you middle place finish in the final. It is ‘nearly’ world class. And so, you got to take the bodyfat down to a comparable level with the best sprinters to compete against them. Bodyfat is not the most important thing, but it is deffinately one of the factors. Look how lean Usain Bolt is. I simple used my observation to come to the above conclusion.
Remember also, that low bodyfat, often means less work for the heart. Do you know that it takes a lot of blood and capilaries to maintain one pound of fat? I wish I could remember the numbers and referance, but it was quite startling. Those with lowerbodyfat, have less work to do (for the same tasks to be completed) over each 24 hour period, and so they absoluteley recover quicker between training sessions. They are less likely to get lethargic, and are more likely to be energetic. (feeling ‘up’ for a training session.)
Also, I have seen papers that show a correlation between slightly faster track times at end of a soccer season (than at beginning of season). For practically all memebers of the team. They all had slightly less bodyfat % at the end of the season than pre-season. That was the correlation mentioned, in the study.
Also, there was a paper on school children and 40 yard dash times. The ones that had lower bodyfat were the fastest kids in the study.
The fastest dog is also the breed with the lowest bodyfat. The Greyhound. (Even ones that were not trained to participate in the sport, had lower bodyfat than other breeds of dog.)