Are you are constantly tired even after a good night’s sleep. What does this problem stem from? ‘Sleep is a good indicator of a person's overall health and their relationship with their environment,’ says Dr Valaxt, a researcher at the National Institute of Health and Medical Research in France.Only a quarter of British adults say that they sleep very well most nights, while over half lose sleep over worry and stress. 7% get less than five hours of sleep per night, and the same amount sleep for eight or nine hours.Food, exercise and hydrationIn order to be fit and efficient, it is essential to have a good night's sleep, but sleeping well is not enough to make sure you have enough energy for the day.US scientists from the University of Georgia have conducted an investigation into the subject. They discovered that athletic people were more energetic and awake than those who were more sedentary. Diet also has an important role when it comes to fitness. To be energetic, you have to eat fruits and vegetables, and protein and iron-rich products. Dr Veronica Van der Spek states:By improving your nutrition, one can easily offer better resistance to fatigue and stress.Other factors can also improve your physical health such as hydration, not skipping meals, feeling fulfilled with your life... If after all these changes you still feel tired, then you can opt for vitamins or dietary supplements!