More or less does the opposite, exercising burns a lot of fuel and is a stress to the body, both will lower ketones. Don’t waste the strips within a couple hours of working out. Exercise is great keto or not, don’t let ketone levels tell you otherwise.
Think of it from a sugar burning view, you eat a bunch of carbs and pretend we have a “carb level” in your blood and glycogen in your muscles, if you work out hard for a while and retest, you won’t have more, you’ll have LESS as you’ve burned them up. We don’t work any different with ketones. Once there is more need your liver will make more. The longer you’re keto the more “on demand” your ketone production becomes. Most of us that have been doing this long term always have crap levels, really makes no difference most of the time.