What does the "spread of effects" of amplitude based training indicate?

The "spread of effects" of amplitude-based training refers to the concept that when a specific skill is trained, especially in the context of motor skills, the benefits extend beyond the targeted area or skill, impacting the entire motor system. This principle suggests that when individuals engage in amplitude-based training, the neural pathways associated with movement may be positively influenced in a broader manner.

In the context of Parkinson's disease and LSVT BIG, this means that improvements in big movements not only enhance the trained movements but can also lead to positive changes in other areas of motor function. For example, an individual who trains to improve their walking may also experience enhancements in balance or coordination, demonstrating the interconnected nature of motor control systems.

The other options do not capture this principle accurately. The notion that training is limited to the trained skill or to specific domains such as speech and swallowing does not encapsulate the broader effects observed with amplitude-based training. Additionally, indicating that results are only visible in advanced stages of Parkinson’s disease does not align with the evidence supporting early intervention and its benefits.