Note that i used the phrase "better considered decisions" which is not the same as making a "quick decision". Decision making is improved during Walking while you need some variable time after Strenuous Exercise when your Arousal state has calmed down to make better decisions.

The Inverted U Hypothesis (aka Yerkes-Dodson law - https://en.wikipedia.org/wiki/Yerkes%E2%80%93Dodson_law) and https://www.mindtools.com/pages/article/inverted-u.htm was the first to posit the relationship between Arousal and Performance. However there are lots of nuances to this. The important one is Cue Utilization Theory (https://www.elitetrack.com/blogs-details-7362/ and https://psychology.iresearchnet.com/sports-psychology/percep...) which is relevant for decision making.

Coming to Exercise Intensity and Decision Making you may find the following papers helpful for some empirical data.

* Influence of exercise intensity on the decision-making performance of experienced and inexperienced soccer players - https://pubmed.ncbi.nlm.nih.gov/19454768/ and Fontana's thesis at https://core.ac.uk/download/pdf/12206332.pdf

* Effect of Exercise Intensity Level on Choice Reaction Time - https://journals.sagepub.com/doi/full/10.2466/11.03.CP.4.3

PS: I have linked to two relevant books in another post of mine in this thread which you may find useful.