Unfortunately, when the information is posted, some people criticize it by saying that Ramadan is not the time to focus on fitness, and thus the information isn't relevant. First, they make a good point--Ramadan is not the time to focus on fitness. Worship of Allah should be the focus, and the priority. When I hear people make this criticism though, it makes me sad, because it's like saying that fitness isn't important at all, and that we should disregard it in Ramadan.
But I don't think that's realistic. In general we can't disregard school, or work because it's Ramadan (though I get the impression that in some countries people do.) But since fitness can actually make us stronger and better Muslims, and requires year-round consistency, I think it's worth talking about fitness in Ramadan. Not to the exclusion of the importance of worship, of course, but after reading several articles and listening to short talks about the subject, fitness is never placed above worship. Workouts are scheduled around suhoor, iftar, and taraweeh times so as not to conflict with worship and practices from the sunnah.
This audio advice from FitMuslimah.com makes special note of the importance to not set high fitness goals in Ramadan--rather, the goal should be to maintain one's current level of fitness. It's not practical to do much improvement--which requires a specific calorie intake and exercise routine while fasting. In fact, attempting to do so might actually negatively affect the body.
But for people who are used to eating healthy (whether to maintain blood sugar or other health reasons, for weight loss/maintenance, weight gain, or other kinds of training) why should they stop in Ramadan? For people who are used to regular exercise (for its many health benefits) why should they stop in Ramadan? And lose what they work for the rest of the year?
For anyone who isn't used to exercise, Ramadan might not be the best time to start with intense workouts, but a brisk or moderate-paced walk wouldn't go amiss.