The National Stadium will open its doors tomorrow for the beginning of the athletics. Within the first hour of events are the men’s 100m heats. In the first heat and second lane, world record holder Usain Bolt lines up ready to begin his campaign for 100m-200m gold. The last male sprinter to do the sprint double was Carl Lewis in Los Angeles 1984. Bolt will of course need to defeat, amongst others, his Jamaican team-mate Asafa Powell if he is to do the double.

The Jamaican athletics team have been in the news recently, complaining that their team has had to do an ‘extremely unusual’ amount of blood tests for the drug testing in Beijing. Powell claims he has done so many tests he’ll be weak for the final. He also stated that Bolt has been under the same scrutiny. Why might they be weakened then?

During exercise, a good blood flow to the working muscles is needed to provide oxygen and nutrients. In Beijing where it can get very hot and humid a good blood flow to the skin is also required for cooling. However, as blood volume drops due to loss of water from sweating, heart rate rises to maintain blood flow to the muscles. This means the athlete has reduced economy and generally less tolerance to exercise. At the same time, blood flow to the skin is reduced, probably because it's more important to maintain circulatory blood volume. Thus cooling is impaired and body temperature rises. This increased body temperature may also contribute to the weary feeling during endurance exercise in the heat. The immune system is also threatened by the reduction in white blood cells.

(To find out more about how heart rate affects training and performance read this heart rate training report)

Can officials be blamed? Not really. The last time the games were in the Far East Ben Johnson tested positive for anabolic steroids after his 9.79 victory in Seoul 1988. Athens 2004 winner American Justin Gatlin is currently serving a four-year ban for doping offences. Add to this the fact that Jamaica only set up a domestic doping commission days before the Olympics started, and one of the athletes failed an IOC test during June, it is not surprising that their team has been slightly victimised. Also with Bolt’s PB at 9.72 and Powell’s 9.74, it’s also nice to know these athletes are genuine phenomenons. It’ll make analysis of their performances in the next couple of days all the more intriguing.

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