Page 127 - Petelin, Ana, Nejc Šarabon, Boštjan Žvanut, eds. 2017. Zdravje delovno aktivne populacije ▪︎ Health of the Working-Age Population. Proceedings. Koper: Založba Univerze na Primorskem/University of Primorska Press
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during a given period continues to decline with increasing levels of physical physical activity, physical fitness and prevention: role for the working population 125
activity and cardiorespiratory fitness. This is true for both men and women and
across a broad range of ages from childhood to the very elderly. These findings
are derived from prospective non randomised cohort studies with predefined
study groups, with physically active and a control group, a current standard in
epidemiological research. Further evidence on the benefit of physical activity
are derived from four large meta-analyses (Class I, Evidence A, Grade strong)
(Löllgen, 2013, Löllgen et al., 2009) (Figure 1). These meta-analyses have been
adjusted for confounding risk factors (i.e. smoking, diet etc.).
Sedentary lifestyle
In the last years, there is growing evidence that negative effects of sedentary
lifestyle is significantly enhanced by sitting time per day, especially the so-
called „screen-time”, that is watching TV, PC-work, PC games and surfing the
internet. A recent meta-analysis confirmed this to be a significant cofactor for
cardiovascular risks (Class I, Level A, Grade strong). Most of the mortality-re-
duction effect seems to rely on a decrease in cardiovascular and CHD mortal-
ity. The level of decreased coronary risk attributable to regular physical activi-
ty is similar to that of other lifestyle factors such as avoiding cigarette smoking
or Mediterranean diet. The risk of CVD (including CHD and stroke) or CHD
alone is significantly reduced in more physically active or fitter persons, with a
relative risk reduction nearly twice as great for cardiorespiratory fitness (CFR)
than for physical activity increase at all percentiles (Kokkinos et al., 2006, Kok-
kinos et al., 2016). A possible explanation for the stronger dose–response gra-
dient for fitness than for physical activity is that fitness is measured objective-
ly, whereas physical activity is assessed by self-reports and questionnaires that
may lead to misclassification and bias towards finding weaker physical activi-
ty or health benefit associations (Moore et al., 2012). Altogether, sedentary life
style, too much sitting and screen time over hours can be summarized as Ex-
ercise Deficiency Syndrom (EDS) as an important risk factor for many diseas-
es in the working population.
Physical activity intensity (Dose – response relationship)
Some meta-analyses also present data on dose-response relationship for phys-
ical activity vs risk reduction. The results of all studies confirm a non-line-
ar relationship (Shiroma et al., 2014). The most significant relative decrease of
mortality occurs from sedentary lifestyle or inactive phase to low or moderate
intensity of physical activity. This then means that little activity is better than
nothing.
Change from moderate to vigorous activity increases training response
and additionally reduces the relative risk for mortality, but to a lesser degree
(percentage) than the first (moderate) intensity category. This is emphasized by
the flattening of the dose response curve with very vigorous activity. Two re-
activity and cardiorespiratory fitness. This is true for both men and women and
across a broad range of ages from childhood to the very elderly. These findings
are derived from prospective non randomised cohort studies with predefined
study groups, with physically active and a control group, a current standard in
epidemiological research. Further evidence on the benefit of physical activity
are derived from four large meta-analyses (Class I, Evidence A, Grade strong)
(Löllgen, 2013, Löllgen et al., 2009) (Figure 1). These meta-analyses have been
adjusted for confounding risk factors (i.e. smoking, diet etc.).
Sedentary lifestyle
In the last years, there is growing evidence that negative effects of sedentary
lifestyle is significantly enhanced by sitting time per day, especially the so-
called „screen-time”, that is watching TV, PC-work, PC games and surfing the
internet. A recent meta-analysis confirmed this to be a significant cofactor for
cardiovascular risks (Class I, Level A, Grade strong). Most of the mortality-re-
duction effect seems to rely on a decrease in cardiovascular and CHD mortal-
ity. The level of decreased coronary risk attributable to regular physical activi-
ty is similar to that of other lifestyle factors such as avoiding cigarette smoking
or Mediterranean diet. The risk of CVD (including CHD and stroke) or CHD
alone is significantly reduced in more physically active or fitter persons, with a
relative risk reduction nearly twice as great for cardiorespiratory fitness (CFR)
than for physical activity increase at all percentiles (Kokkinos et al., 2006, Kok-
kinos et al., 2016). A possible explanation for the stronger dose–response gra-
dient for fitness than for physical activity is that fitness is measured objective-
ly, whereas physical activity is assessed by self-reports and questionnaires that
may lead to misclassification and bias towards finding weaker physical activi-
ty or health benefit associations (Moore et al., 2012). Altogether, sedentary life
style, too much sitting and screen time over hours can be summarized as Ex-
ercise Deficiency Syndrom (EDS) as an important risk factor for many diseas-
es in the working population.
Physical activity intensity (Dose – response relationship)
Some meta-analyses also present data on dose-response relationship for phys-
ical activity vs risk reduction. The results of all studies confirm a non-line-
ar relationship (Shiroma et al., 2014). The most significant relative decrease of
mortality occurs from sedentary lifestyle or inactive phase to low or moderate
intensity of physical activity. This then means that little activity is better than
nothing.
Change from moderate to vigorous activity increases training response
and additionally reduces the relative risk for mortality, but to a lesser degree
(percentage) than the first (moderate) intensity category. This is emphasized by
the flattening of the dose response curve with very vigorous activity. Two re-
