Dr Tertius Kohn's research suggests that focused training rather than
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
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
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
According to his research, it seems that black athletes simply train harder
than their fellow athletes, rather than being "born" with
"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.