You could be exercising for too long... Did you know that if you are exercising for longer than 75minutes then you could be doing more harm than good.
How is this so? Well, during your workout you are using carbohydrates as fuel and your body uses hormones to function, like testosterone. However after 75mins (or around that time, depending on your body type), these hormones will begin to drop and your carbohydrate intake to the muscles will plummet. By this point you want your workout fully wrapped up and ready for your post workout meal/shake.
If not, you could be doing more harm than good. If you continue to exercise then you run the risk of your body going into a negative state. As energy depletes you won't be burning and using the correct fuel for your session, and could further break down muscle tissue (catabolism) that you have built up over time.
Be sure to use the right supplements whilst you train so you can slow the process of catabolism, and still have effective and great workouts. If you need some help, get in touch!!