Following a stroke, use of your affected hand can be one of the most important but challenging to rehabilitate efficiently. While the age-old adage of practice makes perfect can still apply to hand training, the way you practice may make a considerable difference in your results. With ‘constant’ practice, you perform the same task repeatedly in a controlled manner. In contrast, with ‘variable practice,’ you perform the same task but in a variety of ways. Constant practice has been shown to cause you to make fewer errors than if you practice with more variety. However, variable training is better for generalizing the learned movements to tasks other than the one practiced. So, which one is better for patients with hand weakness after stroke?
The effects of variability
Researchers from Hungary studied the difference between variable and constant training on the ability of the affected hand to generate force. They recruited 33 patients and divided them into two groups, one for constant and one for variable practice. Researchers measured the maximum strength of hand grip before initiating training. Patients practiced 80 force exertions a day for four consecutive days. The constant group exercised at 25% of their maximum force. The variable group practiced at five different levels of their maximum effort: 15, 20, 25, 30, and 35%. After each trial, the patients got feedback regarding the force they produced. On the fifth day, participants performed two tasks: one at 25% and one at 40%, without feedback.
Variable beats constant practice
Both groups of patients were able to learn to produce the required force. However, the variable group showed the best performance at the 25 and 40% task. Neither group practiced the 40% task previous to the fifth day. Therefore, it best represented how well the practiced techniques translated to an unpracticed task. As expected, the variable group’s training was more generalizable. However, it also demonstrated more errors when strictly asked to perform the practiced task.
These findings are in line with the results of healthy participants, who regularly rely on adaptability for performing a broad spectrum of precision tasks. Although the long-term effects were not studied, it is worthwhile noting that overall, variable practice showed better outcomes than constant practice in this study. If you are struggling with precise hand tasks following a stroke, you may wish to inquire about implementing additional variability into your rehabilitation regimen.
The lead author of the original article was Dr. Tibor Vámos, National Institute for Medical Rehabilitation and Bárczi Gusztáv Faculty of Special Needs Education, Institute for Methodology of Special Needs Education and Rehabilitation, Eötvös Loránd University, Budapest, Hungary.