Fitness and Health Benefits of Physical Activity
There is considerable interest in the health andfitness benefits of a physically active
lifestyle among youth. The study of relationships between physical activity and
health status in youth is challenging in that many of the health risks associated with
inactivity in childhood or adolescence may not present themselves until later in
adult life (Cumming and Riddoch 2008 ). Nevertheless, comparisons of indicators of
health andfitness between habitually active and less active youth and the influence
of specific physical activity programs and/or intervention or activity on indicators of
health andfitness provide insights (Table5.6). Trends are largely based on two
critical summaries (Centers for Disease Control and Prevention expert panel, Strong
et al. 2005 ; Physical Activity Guidelines Advisory Committee 2008 ); other sources
are indicated in Appendix 2.
Space does not permit detailed discussion of the beneficial effects of physical
activity on the respective indicators. Nevertheless, several factors merit consider-
ation in evaluating the health andfitness benefits of regular physical activity.
- A good deal of the evidence considered is based on continuous activity and the
recommendation of 60 min or more per day of MVPA. Most activities of
children and probably adolescents are largely intermittent so there is a need to
evaluate potential health benefits of relatively short bouts of activity. - Intervention and experimental studies of the influence of physical activity on
indicators of health generally focus on outcomes. However, beneficial effects
associated with activity are lost or markedly reduced when programs stop. There
is a need to address the amount and intensity of activity needed to maintain the
beneficial effects on thefitness and health indicators. - There is a need for interventions that are designed, implemented, and evaluated
within the context of contemporary theories of motivation and behavior change.
The theory of self-determined motivation (Deci and Ryan 2000 ), for example,
provides an appropriate framework within which to examine how biological,
psychosocial, and environmental factors may contribute toward the adoption
and maintenance of physical activity in youth. The theory posits that humans
have an inherent need to feel competent, autonomous, and related or relevant to
the group and that conditions which support these needs foster intrinsic moti-
vation, a key ingredient in sustaining behaviors such as effort, curiosity, and
creativity. Applied to physical activity, there is a need to identify and better
understand conditions that foster and/or inhibit inherent desires of children to be
active and in turn encourage lifelong participation in physical activity. - Individual differences in normal growth and maturation are the rule rather than
the exception. Variables of interest generally change with normal growth and
maturation and are influenced by individual differences in the timing and tempo
5 Physical Activity and Inactivity Among Children... 89