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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 1, January/February 2018
AFRICA
35
seasonal, with the pre-season representing a period of strength
development, while the competitive phase of the sport is typical
of peak performance during match play. This suggests that the
training adaptation is non-linear, but rather fluctuates depending
on external exercise demand.
The level of primary sex hormones also alters during the
football seasons and depends on internal (e.g. menstrual cycle
in females) and external stresses (e.g. more resistance training in
males, often to enhance body image). Serum testosterone levels
can influence muscle architecture and function, and it is during
times of peak training stress when the advantages of this anabolic
hormone are most notable. In football, this usually occurs during
the aerobic component of play, when the slow-twitch muscle
fibres are most active. The body adapts by improving cardiac
output, essentially by increasing left ventricular mass,
2
which is
more pronounced in male athletes.
The main limitation of this study is that causality could not
be inferred in this comparative study, indicating the need for
longitudinal studies of adolescent African footballers to confirm
our findings.
Conclusion
This comparative study demonstrated the gender differences
in performance as a result of physiological and cardiovascular
advantages in male subjects. In addition, football training can
remodel body composition, resulting in enhanced jumping
ability, which is essential during competitive match play.
Ms Kendra Dykman and Mr Dane Schaefer captured the collected data.
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