Best times to exercise during Ramadan

Before Suhoor
Ideally, the best time to exercise is just before Suhoor, the pre-dawn meal. It is best to drink a lot of water and wait half an hour before beginning the exercise. The workout should be limited to a low-to-medium intensity one in order to prevent muscle loss.
After Taraweeh
Another good time is to exercise after the Taraweeh prayers. You can complete a medium-to-high intensity workout at this time and also incorporate the pre- and post-workout meal.
After Iftar but before Taraweeh
The period after Iftar but before Taraweeh is the third best option. This is a suitable time for a low-medium intensity workout - but this might be a problem in the UAE since there is only around one and a half hours between Iftar and Isha, making it a bit more difficult to squeeze in an exercise schedule.
After Iftar
The fourth best option is to schedule cardiovascular exercise around a half an hour after Iftar. This could be a quick but high-intensity workout - but this should only be done after eating a light Iftar meal.
All workouts should be kept between 30 to 60 minutes and cardiovascular exercises should be limited to twice a week. Heavy exercise such as running, swimming, heavyweight training etc should be avoided, and light exercises such as push-ups, Pilates, cycling, and full-body stretching are encouraged.
Regardless of whether you're exercising before or after Iftar, if you begin to feel lightheaded, dizzy, or sick, stop all activity and rest immediately.
(Info courtesy: Human Relations Institute & Clinics)