Advances in the Study of Adaptation to Varying Workload Conditions

Background: Attention allocation is a guiding capacity to cognition (i.e., information processing) and effort perceptions. During effort expenditure, attention allocation shifts from a `flexible and dissociative mode` to an `inflexible and associative mode` as the workload increases. Attention shift allows the system to best adapt to an increasingly demanding environment. Specifically, under easy workload, one can `daydream` and enjoy the attended scenes, while under heavy workload, one must pay attention to the exertive sensations stemming from the working muscles and joints. In both cases, attention is the primary mechanism, which aids the biological system to adapt.

Method: A series of studies aimed at expanding the physical effort-exertion-attention linkage was carried out. In each study participants performed either a strength-endurance or an aerobic task until voluntary exhaustion. A battery of tests was administered prior to, during and immediately after task completion.

Results: (a) Attention shifts from dissociative to associative mode as effort sensations signals hard effort; (b) Attention shift from dissociative to associative mode seems amenable to change through the use of imagery; and (c) Lack of visual and auditory stimulation during demanding physical effort affect both attention allocation and perceived exertion.

Discussion and Conclusions: Diverse modalities mediate adjustment to effort perceptions and result in higher adaptation to effort demands. The results of these studies shed light on the underlying mechanisms of coping with physically aversive sensations and suggest methods for coping with and adaptation to physical effort.