It is too hard to determine the individual heart rate changes
even by an experienced heart specialist. Practically, there are
many determinants for a heart rate to slow down, or speed up,
or vary inexplicably. The determinants are not well-known in
the heart disease literature. The maximum, peak and basal
heart rates are generally used values in clinical medicine and
physiology. Generally, the percentage of peak, or maximum,
or a fixed percentage of heart rate is used to prescribe
the intensity of exercise, or medicine in both the rehabilitation
programs and the disease prevention. It is known that a
delayed heart rate recovery during the first and second minute
after acute exercise is an independent predictor of overall mortality. The peak, or maximum, or basal heart rate is widely
used as a criterion for achieving peak exertion in the determination
of maximal aerobic capacity.
Recently, some longitudinal and cross-sectional studies have
pointed that aerobic endurance training accelerates heart rate
recovery after exercise in healthy subjects. In many
clinical settings, exercise testing is not used if subjects attain
an arbitrary percentage of their age-predicted maximal heart
rate . In earlier research articles, mainly metaanalysis
and regression analysis have been used to identify
the determinants of heart rates, assuming the response variance
is constant. Note that the three heart rates basal, peak
and maximum are positive and heterogeneous. For a positive
response variable, the variance may be non-constant, due to
variance-to-mean relationship. Such data set should be analysed
using joint Log-normal and gamma models. The
current data sets (basal, peak and maximum) are positive,
their variances are non-constant, distributions are non-normal,
and the previous statistical methodologies are inappropriate.
In addition, best of our knowledge, there is little study
of heart rates for the DSE data. These issues have motivated
us to locate the heart rate (basal, peak and maximum)
determinants of the DSE data set.
The present report aims to examine the following hypotheses.
What are the determinants of the basal, or peak, or maximum
heart rate of the DSE data set? What are the associations of
the determinants with the basal, or peak, or maximum heart
rate? What are the effects of the determinants on the basal,
or peak, or maximum heart rate? Answer of these hypotheses
are little known in the cardiology literature. These issues are
addressed in the current report.Some continuous positive responses such as basal, peak, and
maximum heart rates have non-normal error distributions.
The class of generalized linear models is used for analysing
such data. In practice, the gamma and the log-normal distributions are often used in modelling positive data. For
some positive response variables, it is often observed that
there exists a variance-to-mean relationship, consequently
the response variance may be non-constant.
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