Chances are you've heard every single one of these, and have acted on them in the past. Though it isn't really a big deal if you've fallen for them, continuing to buy in to myths can cost you some money in the long run. Lifehacker once again posted a quick but useful read regarding these myths, and what you can do to avoid falling for the ever present fitness trends that are going around. In short, here are the four myths:

You need to drink eight cups of water a day
If you're thirsty, you're already dehydrated
Sports drinks are the best option after exercise
Water flushes out toxins from your body

If you'd like to learn more about these myths, you can learn about them here.