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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 2, March/April 2017
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dysregulation may be key aspects in the pathogenesis of
CHD.
5,10,16,23,32-34
These aspects decrease during exercise and may
therefore play a part in the 1.33-fold decreased risk for CHD.
Based on the evidence, it is believed that the CHD benefit
associated with exercise is substantial and should garner a similar
level of public interest as do other risk factors such as smoking,
high cholesterol levels and treatments such as statin therapy.
However, while exercise is frequently advised for healthy living,
36
it is unfortunate that only 48.9% of Americans meet the physical
activity guidelines. It follows from this that 51.1% of Americans
do not meet the minimum physical activity guidelines, which
results in 162.8 million Americans at a greater risk of CHD due
to physical inactivity.
37
The individual studies selected unfortunately represent only
the risk associated with the cohort studied and cannot accurately
be extrapolated to other populations without further research.
Conclusion
Although it is well known that moderate exercise is associated
with a lower risk of CHD, all the positive effects on CHD
pathogenesis were not available in a detailed integrated model.
Such a model would help provide further insight. A high-level
conceptual model was therefore developed, which links moderate
exercise with the pathogenesis, hallmarks and biomarkers of
CHD.
The novel connection graph developed from this model
shows, at a glance, the positive effect of moderate exercise on
certain important aspects of the pathogenesis of CHD. It helps
to graphically explain why moderate exercise is associated with
lower CHD risk. From this it is apparent that exercise has a wide-
ranging impact on the pathogenesis of CHD, with these effects
notable in changes in CHD biomarkers.
The integrated high-level CHD model and simplified
connection graph provide a summary of evidence for a causal
relationship between CHD risk and moderate exercise. We
acknowledge the fact that the integrated view is relevant to
other lifestyle issues and for full comprehension will have to be
replicated in other articles describing these factors.
The angel investor was Dr Arnold van Dyk and the research was later self-
funded. Prof Leon Liebenberg was involved in the initial research.
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