Thanks for reply, I did forget to say that it is not everytime I do get the headaches but at least once a week, will try having 3 tall glasses fluid in the morning, I have been having 2, I do have porridge oats most mornings with raisins and sunflower seeds, is this enough carbs?

Hi I am new on here, been at gym for over two years, not overweight or anything, trying to up fitness levels and doing more exertive classes like advanced step aerobics, body combat and spin, problem is when I am halfway through the class I am getting a massive headache suddenly start which hurts mo...