Ambulatory feedback at daily physical activity patterns

Patients with chronic fatigue syndrome (CFS) are characterized with persistent fatigue which disturbs activities of daily life. CFS is a symptom-based diagnosis that is made without findings of distinguished physical examination or laboratory tests. CFS can be diagnosed if the fatigue lasts for at least six months, is of new onset, is not the result of persistent physical exertion, does not improve considerably by taking rest, and has resulted in substantial loss in professional, social or personal functioning. Furthermore, patients must report four out of eight symptoms i.e. unrefreshing sleep, post-exertional malaise, headache, muscle pain, multi-joint pain, sore throat, tender lymph nodes, and concentration and memory impairment. The goal of this thesis is to study whether ambulant monitoring of and providing direct feedback on daily physical activities can improve the balance in the daily physical activity pattern and result in improved treatment outcome in patients with CFS. To achieve this goal the daily physical activity pattern is studied in patients with CFS. Subsequently, a 'state of the art' feedback system is used to investigate the potential value of ambulant feedback at the daily physical activity pattern in the treatment of CFS.