Page 153 - Physical activity in recipients of solid organ transplantation - Edwin J. van Adrichem

di

Physical activity in recipients of solid organ transplantation
aspects such as the expenses, availability, and logistics creates limitations for its application.

of assessment such as questionnaires and activity diaries. In this thesis, questionnaires were
utilized for the physical activity level assessment in Chapter 2 and Chapter 6
.

e use of
e most frequently used, especially in more comprehensive studies, are subjective methods
erent assessment methods to measure physical activity, di
variety in what is being reported in publications limits the comparability between studies.
the variable nature of physical activity between the seasons and seven days makes daily

erent outcome measures, and
Although questionnaires have been utilized broadly and already for over 50 years,
they still show limited reliability and validity.
questionnaires, however, can be used for classifying a (large) population into categories of
physical activity behavior (i.e., inactive/ moderate active/ active) but are not to be used to
24
Validation studies have showed that
assess the energy expenditure at the individual level.
24,25
Under- and overestimation of
physical activity can occur due to several factors including social desirability, perception,
cultural factors, age, complexity of the questionnaire, memory of the respondent, seasonal
variation, and length of the period surveyed.
24,25
A recent review regarding the
measurement properties of self-reported questionnaires to measure physical activity
concluded that ambiguity in terminology, persons’ reporting of actual physical activity, and
physical activity di

cult to assess with self-reported questionnaires.
26
Further validation
and assessment of responsiveness and interpretability of physical activity questionnaires
would be valuable for specifying the level of physical activity required to decrease the risk
for chronic diseases or conditions.
26
However, in order to obtain insight into an
individual’s level of physical activity for possible intervention, measures that are more
accurate are necessary. Information that is more detailed is worthwhile from the
professional’s perspective so as to aggregate data to be employed in coaching or setting up a
treatment plan. For the recipient, it will assist in obtaining insight into their actual physical
activity level and monitoring their longitudinal change.
One of the methods to obtain information that is more accurate is by not only
assessing the level of physical activity but also the level of physical

tness. Physical

tness
refers to the attributes that people possess or achieve that relate to their ability to perform
physical activity.
27,28
Several components of physical

tness such as cardiorespiratory
endurance, muscle strength and endurance, body composition, and balance are associated
with health and functional capacity. Physical

tness was measured in the studies described
in Chapter 3 (functional exercise capacity) and Chapter 7 (maximal exercise testing).
Assessment of physical

tness can provide important diagnostic and prognostic
information in a wide variety of clinical and research settings.
laboratory or
eld assessment methods. A well-known method of laboratory testing is
It can be performed with

29
adequate testing facilities, the need of a physician being present, and the costs of testing are
maximal incremental exercise testing that determines a recipient’s maximal or peak oxygen
uptake. Although the information generated with a maximal incremental exercise test is
worthwhile to determine factors that limit a recipient’s exercise performance (i.e.,
pulmonary limitations, cardiovascular, or peripheral muscle limitations) and can provide
speci

c information to be used in composing a training schedule, unfortunately, it is not
widely applied in the rehabilitation or transplantation settings.

e insu

cient number of
151.
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