Special Challenges to Assessment of Physical Activity

The comprehensive “Guide to the Assessment of Physical Activity:.Clinical and Research Applications,” published in Circulation and first available online October 14, 2013,¹ was written to provide a rationale for the importance of assessing physical activity, to explain key concepts relevant to the assessment process, and to provide an overview of the options for assessment. The guide is both informative and practical in that it provides a Decision Matrix to help clinicians, as well as researchers, determine the type of assessment tool that will be most useful and relevant. The guide, comprehensive as it is, leaves many questions remaining in the assessment process. Specifically, these include the special concerns and challenges to assessment in special populations such as older adults with cognitive impairment or those with obesity. For example, older adults with cognitive impairment may not be able to report physical activity due to limited recall. Information may need to be obtained from a caregiver. Although not included in the review, there are some measures in which caregivers report the physical activity of the individual when he or she is unable to recall that information. One such measure is the Physical Activity Survey for Long Term Care (PAS-LTC).² This is an observational survey measure of physical activity developed for use with long-term care residents. The measure includes six categories: routine physical activity; personal care activities; structured exercise; recreational activities; caretaking activities; and repetitive activities (e.g., pacing or fidgeting with an object). Within these six categories there are 66 specific activities. Each item has a description of the activity to be observed. Prior use of the measure provided evidence of criterion-referenced validity (r=0.55-0.60, p<0.05) and inter-rater reliability (r=0.82-0.94, p<0.05).^2,3

Another special challenge to assessment of physical activity is related to the wearing and placement of the many different types of accelerometers and pedometers and their subsequent reliability and validity. Evaluating individuals who are obese, for example, may require the use of special devices and/or location of the device.⁴ Similarly, in patients with Parkinson's disease specific location of and type of accelerometer or pedometer provide more accurate information than others. Given these types of challenges, it may be useful to remind the providers to think about these types of challenging populations when using the Decision Matrix.

Physical Activity Domains…Have We Thought of Everything?

The guideline differentiates between the different physical activity domains with consideration given to occupational, domestic, transportation, and leisure time. For retired older adults, particularly those who may be living in long-term care facilities, these four domains are not reflective of the domains of physical activity that may encompass their daily lives. Activities of daily living, such as bathing and dressing, may be perceived by some frail, older individuals to be a moderate intensity physical activity. The occupational category could be expanded to include volunteer activity and/or caregiving. There are some subjective measures of physical activity, such as the Yale Physical Activity Survey (YPAS),⁵ that include a few of these options (i.e., caregiving is included as is recreational activities). Generally, however, commonly used survey measures don't sufficiently expand on low-level activities that are particularly relevant for those with cognitive impairment or physical frailty.⁶

Assessment to What End?

The intention of this guide to the assessment of physical activity was to (1) facilitate dissemination of the public health recommendations for physical activity that were initially released in 1995 and revised in 2008 and disseminated as a federal guideline for physical activity⁷; (2) encourage assessment of physical activity among primary care providers; and (3) delineate the many ways in which assessment can be performed. The guide reiterates the point that there is now sufficient evidence that physical activity is beneficial to all adults. Further it alludes to the fact that the real challenge is getting adults to engage in a sufficient level of activity to achieve the physical and psychological health benefits that can occur. Physical benefits have been noted to include decreased mortality, primary prevention of coronary heart disease, improved lipid profiles, modification of body composition with reduction in age-related sarcopenia, primary and secondary prevention of type 2 diabetes, primary prevention of stroke, improved blood pressure, decreased risk of some cancers, prevention of falls, cognitive benefits, and improved strength and muscular function.^8-10 Psychological benefits include such things as decreased depression and anxiety.^11,12 Given the well-supported benefits of physical activity, how can assessment help to facilitate engagement of all adults in regular physical activity? Assessment should be considered as a way in which to (1) help assure that the physical activity plan recommended for the individual is consistent with his or her abilities; (2) serve as a benchmark for motivating the individual to initiate and adhere to regular physical activity; and (3) guide the ongoing study of physical activity and associated risks and benefits for all adults.

Matching Physical Activity Program with Ability

Despite the overwhelming benefits of physical activity there can be some costs or risks when the wrong type of activity is done and trauma occurs. Musculoskeletal injuries are the most common adverse outcomes associated with physical activity among adults.^13,14 These are more likely to occur when activities are being done that exceed the individual's ability and/or that the individual is not correctly or safely performing. Starting a resistance training program with a weight that exceeds ability, for example, can cause muscle damage. An older individual who initiates vigorous physical activity without appropriate training to build up to that intensity of activity may experience cardiovascular symptoms or experience a cardiovascular event.^15,16 Therefore, accurately evaluating what patients are currently doing in terms of physical activity is critical to the development of appropriate physical activity plans. Ideally it may be helpful to assess patients at baseline with both subjective assessments (e.g., the YPAS) and objective assessments (e.g., number of steps walked in a day based on a pedometer or actigraphy). In so doing, the provider would have more accurate information about what each patient believes he or she is doing in terms of activity and what he or she is actually doing. Realistic goals and a safe and effective physical activity plan could then be established.

Guide the Ongoing Study of Physical Activity

Globally, as noted above, there is sufficient information to support the benefit of physical activity. The research supporting these findings generally follows an intention-to-treat philosophy or in descriptive epidemiological studies is based on subjective reporting of physical activity. In intervention studies, we assume that the study participant has engaged in the level of activity prescribed (i.e., the intervention being studied). Little work has been done to utilize treatment fidelity data, such as daily activity counts or daily reporting of activity. Data from the many different types of approaches to assessment of physical activity can be used to perform secondary data analyses and to explore the benefits associated with different levels of physical activity as measured on a daily basis. Increasingly, there is an interest in considering the impact of spending less time in sedentary behavior versus assuring that recommended daily physical activity guidelines are being achieved.^17-19 Assessment data are invaluable for these purposes.

Benchmarking as a Motivational Technique

One of the benefits of assessment of physical activity is that it can serve as a source of motivation for some individuals. For example, objective feedback that one is only performing 1,000 steps a day may help to motivate the individual toward a goal of walking 3,000 to 10,000 steps daily, depending on ability and desired benefit.¹⁷ Survey information likewise could be used to establish how long the individual, for example, spends doing housework. This information could provide a basis for how to increase time in physical activity by increasing time and intensity of vacuuming or washing the floor. Time spent pushing a wheelchair or stroller during caregiving identified during an assessment of physical activity could be used to motivate an individual towards increased time spent in these activities. Alternatively, some individuals are motivated to achieve an increase in heart rate and to work towards a targeted heart rate of 50% to 70% of their maximum heart rate (the simple formula being 220 minus age in years). Although this is well known to be a very gross estimate of exercise intensity, it can be useful as a motivational technique and thus often can be built into treadmills and other types of exercise equipment.

Conversely, it is important to be careful that when doing assessments of physical activity it is not de-motivating or interpreted as a reason why the individual should not engage in some level of physical activity. When reported subjectively, physical activity generally exceeds what is seen on objective assessments such as those obtained from accelerometry.²⁰ Reporting findings from objective measures of physical activity, such as actigraphy, that demonstrates the individual has done very little physical activity may be demotivating. He or she may have perceived/believed that his or her performance was sufficient. This needs to be cautiously reviewed with the individual and presented in a way that will be useful and goal directed.

Given the potential utility of assessment tools as motivational, it may be helpful to add another column entitled "Motivation" in the first row of the Decision Matrix (the question: What is your primary outcome variable of interest?). Encouraging the use of physical activity assessment tools as sources of motivation will also help to remind providers of the importance of motivating patients in changing sedentary behavior and moving toward more active lifestyles.

What Follows Assessment?

Assessment of physical activity among adults is a critically important first step in our greater public health problem of endemic sedentary behavior. It will be up to the provider to not just assess but to utilize the information obtained, review it with the patient, set goals, and continually follow-up with patients by asking about their physical activity during all routine and acute health care visits. In addition to assessment, providers need to know what to prescribe/recommend with regard to physical activity and how to integrate behavior change techniques into their routine interactions with patients. The ultimate focus should be on how to motivate patients to engage in regular and appropriate physical activity.

Primary care providers cannot do this alone. Consideration of a team approach is greatly needed if we are to truly achieve the goal set in Healthy People 2020 related to physical activity and the Global Cardiovascular Disease Taskforce goal of a 10% relative reduction in the prevalence of insufficient physical activity. In primary care offices there may be nurses, social workers or psychologists that can help with this critically important aspect of increasing time spent in physical activity. There are also some simple screening tools that can help with next steps in this endeavor. One example of this is the Exercise and Screening for You²¹ measure. This screening tool (Table 1), which is accessible online, includes six simple questions that provide guidance for the type of activity program that will be safe, successful, and beneficial to the individual.

Conclusion

The use of the Decision Matrix is a great first step to helping primary care providers change their office or facility approach to physical activity assessment. The Decision Matrix can help determine how to assess patients on a regular basis. The next step is using the assessment results to establish an individualized physical activity plan and goals. That plan, and the goals established, can then be reviewed with patients during each follow-up visit. Lastly, primary care providers should be encouraged to assess themselves, develop their own physical activity plans and goals, and share their successes and failures with their patients!