Sometimes the physical condition of our health had a great effect on our sexual activity. Aside from this we should be healthy emotionally and mentally as well. There are still other reasons why there will be a sudden change in your sexual life. Like what they had said here stay away from stress and you should check on your weight too if you are overweight or underweight this things also affects your sexual activity. The kind of physical workout or exercise you are doing is also one reason behind it.