I routinely exercise while holding a dry fast. I can tell you from experience that doing this is fine. You just have to pay attention to your body. For me i can tell i need to ease up when i start to get woozy.
I do workout ( light as days go on ) during my extended dry fasting.I do some running ( < 5km ), brisk walking ( 10.000 steps a trip ), weight training and sometimes also sauna.I do pay A LOT of attention to my body signals and DON’T OVERDO when it call me!The more you fast the more your body will talk to you if you agree to pay attention to it.