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It is well-known that athletes from Africa are among the world's top long distance athletes. The reasons for their success have been a controversial subject of debate between sport scientists.

New research from Stellenbosch University now ascribes the success of black athletes in especially long distance events to their focussed training regimes and principles.

That is according to research conducted by physiologist Tertius Kohn, who receives his doctorate degree in Biochemistry from the University of Stellenbosch in December 2006.

As part of his thesis, Tertius, a former Matie gymnast, looked at the role that physiological and biochemistry factors play in the characterising and adaptation of skeletal muscle during long distance training. He focused specifically on physical changes and protein expression.

He compared the performance of various ethnic groups by grouping thirteen Xhosa and thirteen Caucasian athletes according to their training volume, time over specific distances and preferred racing distance.

Biopsies were done on the muscle tissue of these paired athletes. Tertius looked at the volume of red fibre cells (which is preferred for long distance athletes), intermediate fibre cells (for good middle distance performances) and white fibre cells (ideal for shorter distance athletes), as well as hybrid fibres that fall between these groups.

He found that the percentage of hybrid fibres co-expressing fast-glycolytic and fast-oxidative properties decreased with increased training (>50km/wk) and preferred racing distance (>8km) with all athletes in his training group. He also tested these findings against the results of non-athletes.

Although most black long distance runners are shorter and weigh less (possible genetic characteristics) it was found that they only differ in three factors compared to white athletes.

During sub-maximal tests it was found that black athletes produce less lactate in their blood. This finding collaborates with similar findings by a Danish research group with which Tertius worked.

On a muscular level, it was found that black athletes have more fast-oxidative vessels in their quadriceps muscles, as well as higher lactate dehydrogenase (LDH). LDH is the enzyme responsible for the production of lactate.

Interestingly enough, the activity of this enzyme was also higher in the various types of fibres of the black athletes, and therefore not because of the occurrence of higher type IIa fibres. No noteworthy differences between the activities of other enzymes (such as fat metabolism enzymes) were found between athletes from various ethnic groups.

After noting that the volume of hybrid fibres correlate with the volume and intensity of training, and that the LDH activity was higher in black athletes, Tertius subjected athletes from various ethnic groups to a six week intensive training session on a treadmill. He found no significant differences in their body functioning. He did, however, discover that the LDH enzyme in the muscle tends to increase after training. Although not significant, it was also shown that the lactate levels dropped after the high intensity training followed by sub-maximal testing.

According to his research, it seems that black athletes simply train harder than their fellow athletes, rather than being "born" with extra-special abilities.

"The genetic composition of a person can still determine whether or not he or she will become a top athlete, although this seems to play a smaller role than previously thought," Tertius warns.

Tertius says that the psychological aspects of why certain athletes take part in sport should also be taken into account.

According to Tertius, more debate is needed on the role of hybrid fibres, but he suggests that it might be used to "fine tune" muscle fibres, as well as assist in the transformation process into other fibre types.

"Basic fibre types are firstly determined by the genes inherited from you parents. Athletes, however, can change their fibre types to a degree by following the correct training programme," he believes.

2006-12-10 13:16:05 · answer #1 · answered by Anonymous · 1 0

Because they are out on the sandlots playing Basketball and Football from the time they are 3 years old. They don't sit in front of TV's and computers playing video games and becoming lard asses, but are outdoors excersizing and developing those athletic skills. Most are from poor backgrounds and don't have all the high-tech gadgets like a large majority of whites.

2006-12-10 13:12:08 · answer #2 · answered by Pablo 1 · 1 0

What makes you think that they are? People of African decent are often raised in some level of poverty and many turn to sports as an alternative to the activities of the more well-off, thus they develop their talents like anyone would if they worked at it.
Notice that many people who come from poor families aren't often found in sports that require more wealth -- such as tennis and - increasingly - baseball.

2006-12-10 13:14:50 · answer #3 · answered by skoolboy56 2 · 0 0

I don't think this is true, it's probably just a stereotype.

2006-12-10 20:55:35 · answer #4 · answered by Exotic traveler 4 · 0 0

that's just another incorrect, preconceived notion

2006-12-10 13:09:26 · answer #5 · answered by bata4689 4 · 1 0

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