I am in my forties and am finding that I have good days and bad days. Sometimes I go out and feel great and do a race and get a great time whereas other times my legs feels heavy even when warming up and I feel energyless despite having rested for a couple of days and I struggle to run and get a bad time. I think I am going through the menopause and my periods are erratic, does anyone know how to deal with this as I want to get better not worse?