Kusadikika wrote:@ Alba, that may be one reason. I think another reason maybe just lack of motivation. Running is a solo sport, you are not passing anything to any one, there is no winning when you have not put in your best, there is no shared glory. Messi does not have to shine the whole 90 minutes of a game nor does he need to for his team to win. He can have a few bad passes, a few misses he can even have a few bad games in a season and still be part of and a star of a winning team.
In athletics you must be at your best to win 100% of the time, a bad day results in 100% defeat. You can only have the willpower to be at that level everyday for so long. The physical and mental pressure takes their toll after a while. After you have got what you want which for most people is money the motivation to train and be at your very best all the time just diminishes.
A classic tale is this beautifully told story about Daniel Komen:
http://running.competito...d-to-daniel-komen_27486
The top sportsmen usually get to the top due to hard work. And they generally have large egos. Lack of motivation is rarely a factor. They are making a lot of money due to hard work so they can see the fruits of their hard work.
Secondly, they do not like losing. Do you see the look of distress in runners when they are upset at the finish line? Don't you think Bolt was traumatized at losing the 4 X 100m relay to USA recently and seeing a USA runner taunting him? That kind of taunting would motivate the heck out of anyone.
The difference between Bolt and Messi is that even if Messi gets injured and does not recover fully, he may be slightly slower but still effective. He can still dribble, pass, shoot and out-smart opponents. Runners on the other hand are totally dependent on speed. A slight injury that does not heal properly is the difference between running 9.80 and running 9.95 which puts you out of medal contention. Bolt is still working hard as is Rudisha. But both have picked up significant injuries over the past two years which have made them slightly slower. Its clearly not lack of motivation.
As for Komen, yes I did read that story several months ago. I think he is a classic case of running yourself into the ground. Too many runners run in too many races and burn themselves out. They think they are invincible. Some even run while injured and ruin their careers as was the case with Shaheen who continued to run against Doctor advice.