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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.



  1. 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.

  2. 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.

  3. 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.

  4. 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


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