However, the use of static weighting to serve classes with variable priority levels under input burst traffic may lead to rapid growth of their queues and, consequently, to further packet delay as well as packet loss.
These studies compared the effect of two sets of instructions – variable priority instructions and fixed priority instructions – on dual-task performance following the same training.
Novel skills are learned more quickly when trained under variable conditions and variable priority training leads to greater transfer and longer retention [ 9].
Variable priority instructions, in which participants were asked to shift their attention back and forth between tasks, appeared to be more effective for improving performance than fixed priority instructions, in which participants focused on either the postural control task or the concurrent cognitive or motor task.
Variable priority instructions required the participant to focus on one task at a time (either the postural or the cognitive task) while the fixed priority instructions required the participant to focus on both the postural and cognitive tasks at all times.
Using dual-task exercises with variable-priority or using a complex stepping task may both be closer to real-life conditions as compared to computing while walking.
Participants in the variable-priority training group additionally showed an average of 56% reduction in body sway compared to only 30% of the fixed-priority and single-task group.
Overall, the study showed that variable-priority instruction was more effective in improving both balance and physical performance under dual-task conditions than either the single-task or the fixed-priority training approaches.
In contrast to the fixed-priority training group, the variable-priority group showed long-term maintenance effects on dual-task gait speed for three months after the end of training.
The studies conducted by Silsupadol et al. [ 60- 62] compared three different balance training approaches: single-task balance training, dual-task balance training with fixed-priorities and dual-task balance training with variable-priority.
In the variable-priority condition half the training was done with the instruction to mainly prioritize the postural task and the other half with the instruction to mainly prioritize the additional task.
