To exercise: That is the answer to chronic pain management
The question of whether to exercise or not typically emerges in the setting of chronic pain, as patients fear that moving may contribute to exacerbate their condition. Yet, exercise does exert hypoalgesic effects on chronic pain conditions however variable these effects are, according to a senior physiotherapist who spoke at the Singapore Health & Biomedical Congress 2018.
Physical activity in general increases pain thresholds and reduces pain intensity ratings, says Ms Ivy Fang who practices at the Tan Tock Seng Hospital. In healthy populations, aerobics yield a moderate effect, whereas isometric and dynamic exercises produce large effects.
Changes in pain sensitivity normally occur after exercise, indicating an analgesic response (eg, increase in pain tolerance and lower pain settings). Evidence suggests a dose-dependent effect of moderate-intensity activity on pain sensitivity. The recommended frequency and dose are five times per week of 30-minute walking. [J Pain 2018;19(Suppl):S79]
In chronic pain patients, the effects of aerobic and isometric exercises vary largely according to the specific pain condition and the intensity of activity, among others. The optimal dose needed to produce hypoalgesia has yet to be defined in this population, Fang points out.
“The choice of exercise should probably depend on patient or therapist preferences, therapist training, costs and safety,” she says.
However, chronic pain can be a barrier to exercise, given that patients are in so much pain already, with some experiencing increased pain during physical activity, Fang notes.
Aside from increased experience of pain, other factors said to deter compliance to exercise and treatment success include not enough time/energy, difficulty of activity, absence of support, and lack of facilities or safe environment.
According to Fang, adherence can be improved by increasing supervision, implementing motivational interventions and family involvement and group programmes, and treatment individualization.
Prescribing exercise based on preferred intensity by the patients is especially an important strategy to improve adherence, she continues. One reason for this is the reported inverse association between exercise intensity and adherence rates. Also, patients fear that intense workouts may increase their pain further.
Self-selection of exercise intensity allows individuals to choose that which is necessary to remain comfortable and to minimize possible exacerbations of pain during the exercise bout. In a study involving fibromyalgia patients, such an approach indeed produced positive effects on adherence and pain sensitivity postworkout. [Med Sci Sports Exerc 2011;43:1106-1113]
Exercise is recommended in general and used as a nonpharmacological strategy in the management of chronic pain conditions, Fang says. Its hypoalgesic benefits weigh more than the potential risk of pain exacerbation. For the most part, working out boosts the expression of serotonin, B-endorphins and anti-inflammatory cytokines, all of which play a role in pain modulation.