Integrating physical activity as medicine in the care of people with severe mental illness

People with serious mental illnesses (SMIs) are dying prematurely due to high levels of cardiovascular diseases, and exercise may be part of the solution to this major health inequity. Given the evidence for ‘exercise as medicine’ in general medical literature, we need to consider how physical activity can contribute to the management of people with SMIs. In this debate article, we raise the question how to integrate physical activity as medicine in the care of people with SMIs.

Considering the physical activity continuum

Over the past decade, physical activity research in people with mental illness has increased our understanding of the effects of physical activity at both ends of the continuum (Rosenbaum et al., 2014). At one end of the continuum, sedentary behavior (particularly prolonged sitting) has been shown to increase risk of cardio-metabolic diseases in people with SMIs (Vancampfort et al., 2012), suggesting that multidisciplinary treatment programs should focus on reducing sedentary behavior. At the other end of the continuum, evidence regarding the efficacy of high-intensity interval training in improving physical fitness and managing psychological distress in people with mental illness is growing (Heggelund et al., 2014). Between these two ends of the physical activity continuum are the general health recommendations for aerobic exercise. These recommendations comprise at least 150 minutes a week of moderate intensity physical activity, 5 days a week or 75 minutes of vigorous intensity physical activity spread across the week. In addition, physical activity to improve strength should be performed on at least 2 days each week. It has been argued recently that the major challenge for prescribed physical activity in people with SMIs is engagement and adherence to general health recommendations (Stubbs et al., 2014).

Let’s get physical!—moving from ‘should’ to ‘could’

Prescribing physical activity is not a one-size-fits-all intervention. Psychiatric symptoms, including a-motivation as a component of psychiatric symptomatology, previous physical activity history, side effects of psychotropic medication (weight gain, motor disturbances, fatigue, etc.) and access to services all affect the modality and intensity of physical activity that patients undertake (Stubbs et al., 2014). For example, despite the appeal of high-intensity training, people with SMIs may experience barriers preventing them from engaging in such activities. Inexperience with intense physical efforts, associated fatigue and discomfort, increased risk of physical injuries, limited availability of physical activity facilities and specialized equipment and cost associated with access to facilities or training can all act as barriers. For others, this type of activity may be ideal, which argues for access to trained clinicians with expertise in physical activity prescription and psychopathology. Moderate intensity physical activity may be more achievable, but a 150-minute target may still be unachievable for many people with SMIs. Therefore, we advocate that until more conclusive evidence is available, physical activity recommendations should continue to be as broad as possible. For example, we strongly recommend that people with SMIs should in the first place not to be advised to comply with general population recommendations. Instead, they should be informed that such recommendations are aspirational goals and that sitting less and breaking up sitting time throughout the day will have beneficial effects for their health as well. Health-care professionals should take immediate action and promote reducing sedentary behaviors by introducing light activity throughout the day. Advice on how to accumulate time spent in light physical activity could include getting up from the chair and moving around during television commercial breaks or adding 5-minute walks throughout the day, for example, walking short distances rather than using motorized transport. Adopting small, but incremental, lifestyle changes may better position sedentary people with SMIs to transition to brief bouts of moderate intensity activity as well as muscle strengthening activities. These muscle strengthening activities might, for example, include getting up repeatedly from the chair (increasing gradually). Such an approach will not be constrained by socioeconomic, environmental and organizational barriers, such as lower income, lower education, lack of access to physical activity facilities or time available for leisure. Implementing such interventions, however, requires a shift in culture and system reform, from the design of mental health facilities through to changing attitudes of care providers (e.g. applying the principles of the self-determination theory; see Stubbs et al., 2014).

Would this approach move things forward?

Interventional studies on the long-term effects of reducing sedentary behavior and increasing light activities is currently lacking in people with SMIs. However, evidence in the general population is encouraging, and we cannot sit and wait for evidence in people with SMIs. At a minimum, mental health professionals should briefly assess current physical activity behaviors at every visit and discuss realistic and specific goals that could be adopted, with support and follow-up. Changes in cardiovascular risk factors, functional exercise capacity, and general well-being can then be monitored.

The challenge of recording physical activity levels in people with severe mental illness: a double-edged sword?

It might be argued that when advising people with SMIs on physical activity, health-care professionals should, at first, encourage people to increase their level of physical activity by small amounts rather than focusing on general health recommendations. This includes finding innovative ways to do more lifestyle physical activity at the lower intensity range of the physical activity spectrum. An important major challenge is that, to date, research has not assessed low-level physical activity accurately on a large scale in people with SMIs (Soundy et al., 2014). Accelerometers provide objective measurement of physical activity and are particularly useful for measuring light-intensity physical activities, which may be interspersed throughout the day, and thus more difficult to recall accurately than moderate to vigorous physical activity. In most mental health-care settings, clinicians will not have access to these devices. Interviews and questionnaires are, in contrast, cheaper and easier to use but often prone to systematic errors because of poor recall, in particular in people with SMIs (Soundy et al., 2014). Reliable and valid physical activity instruments that accurately capture sedentary behaviors and physical activity at the lowest end of the physical activity continuum in people with SMIs have not been developed to date (Soundy et al., 2014). One of the most important challenges in physical activity research in people with SMIs is producing a low cost, easy to use, reliable and valid physical activity questionnaire that captures sedentary behaviors and physical activities at the lowest end of the physical activity spectrum.

In conclusion, ‘physical activity as medicine’ is a highly relevant concept for people with SMIs and all members of the multidisciplinary team. Failure to act now with appropriate implementation strategies could prove costly. In our opinion, the 150 minutes a week general health recommendation should not be discarded for this vulnerable population. Rather, we suggest reframing the use of general population guidelines as an aspirational goal, which should not preclude taking an often-difficult first step. Health-care professionals should be aware that a whole-day approach for sedentary people with SMIs, and accepting small incremental improvements in physical activity, would improve the care of this vulnerable population.