Great question! Dark colors, particularly black, do have a tendency to absorb more heat than lighter colors. However, most of these hydration vests are made of moisture-wicking materials that are very breathable and are designed to keep you cooler regardless of fabric color. Personally, if I were to run a race in the desert, I would likely opt for a lighter color vest, but that is probably more psychological for me than an actual performance difference.
Thanks and have a great day!
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