The most frequently used keyword was “exercise therapy,” followed by “stroke,” “rehabilitation,” “peripheral artery disease,” and “intermittent claudication.” All keywords were classified into 6 clusters (#0 cerebral ischemia, #1 coronary artery disease, #2 peripheral artery disease, #3 elderly patient, #4 endothelial function, #5 clock genes) and identified by a timeline in CiteSpace, as shown in Figure 8C. The figure showed the top 10 keywords with the most vigorous citation bursts. This evidence concerns the gene CLOCK and peripheral arterial disease.