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After reading this chapter, you will be able to:

  1. Apply an ecological perspective to better understand physical-activity behavior.

  2. Apply the Stages of Change Model to physical-activity behavior.

  3. Identify the factors that motivate people to consider becoming more active, applying the Health Belief Model and Chaos Theory.

  4. Discuss factors that motivate people to form an intention or decision to increase physical activity, applying the Theory of Planned Behavior.

  5. Describe the influence of self-efficacy on exercise adherence, the factors influencing exercise self-efficacy, and self-efficacy for overcoming barriers.

  6. Set effective exercise program goals.

  7. Apply self-regulation concepts and behavior-change methods for modifying behavior and increasing exercise adherence.

  8. Explain factors associated with long-term exercise adherence.


image Jessica graduated from college last year and has just started a new job as a personal trainer and exercise instructor at a busy fitness center in a large city. One of the most-important benefits associated with her new job is access to the state-of-the-art fitness center where she works, so Jessica can continue her exercise training. Jessica did well in several bodybuilding competitions last year, and she wants to continue training and competing this year. This means several hours in the gym most days. Working at the fitness center seems to be a great way to support her exercise habit. She has to work with a few clients this morning, but then she can get on with her real work: bodybuilding.

Her client Sheila is small, 55 years old, and with a family history of osteoporosis. In fact, her mom is quite bent over, so Sheila is terrified of the condition. She has been monitoring her bone density since she was in her late 40s. After her third bone density test, Sheila received a diagnosis of mild, gradually worsening osteopenia. Her doctor explained that osteopenia is like preosteoporosis and that her bones have lost some mineral, but her risk of fracture is still low. A battery of tests found normal calcium metabolism and no other explanation for her bone mineral loss other than normal aging. Her doctor did not recommend any drug treatment at this point but did recommend that Sheila increase her intake of calcium and vitamin D and also increase her level of physical activity.

Sheila has always enjoyed walking and already walks several times a week for 60 minutes per session. She knows that walking is at least a "weight-bearing" exercise and is helpful for preventing bone loss. Sheila has also read in several magazine articles that weight training is supposed to be very good for keeping bones strong. She has joined the fitness center in order to start a weight-training program. Sheila's membership fee includes one personal training session to help her get started. When Jessica asks Sheila what she is looking for, she says she wants help setting up a weight-training routine to improve her bone density.image

Healthy ...

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