Can resistance training improve hand and finger dexterity and quality of life in essential tremor patients?
Essential tremor (ET) is a common neurological movement disorder occurring in 1 - 5% of the general New Zealand population. ET is typically characterised by a kinetic tremor with the upper limb most often affected. A number of pathologies have been proposed to underlie ET however no definitive consensus has yet been reached.
The enhanced tremor symptomatic in ET can have a serious negative effect on a number of areas including an individual’s quality of life (QoL) and daily functioning. Therefore, finding an effective rehabilitation therapy would be of significant value. Currently a number of medical and clinical treatments such as non-specific medication, surgery and bio-behavioural treatment have been proposed for ET. Each option however, carries limitations, risks and varying levels of effectiveness.
A novel therapy option may be that of resistance training (RT). RT has been shown to induce neuromuscular adaptations such as reduced motor unit firing rate variability and upper limb co-activation. These RT induced changes have been shown to reduce postural tremor and improve manual dexterity in neurologically normal older adults. Therefore this pilot study examined the effect of a general, short-term dumbbell-based upper limb RT programme on upper limb strength, hand and finger dexterity and quality of life in individuals with ET. Six subjects (5 female, 1 male, age: 74 7 years, years diagnosed: 19 7 years) were recruited with one being excluded from the results analysis due to an unrelated hospitalisation. Each participant performed familiarisation and baseline testing prior to undergoing a six week period of RT. This was immediately followed by a post-intervention test and a six week training withdrawal period. A final assessment was then performed after the withdrawal period. Assessment sessions included an upper limb strength examination using a five repetition maximum (5RM) strength test, hand and finger manual dexterity test using the Purdue Pegboard Test (PPT), and two quality of life measures: the Short Form 36 (SF-36) and Quality of Life in Essential Tremor (QUEST) questionnaires.
Following the general RT programme, ET participants experienced significant improvements in some strength and hand and finger dexterity measures. There were however, no significant changes in quality of life. The findings of this pilot study provide evidence that further investigation into RT as a potential therapy for ET is warranted.