You have probably heard it before. It's important to keep yourself fit and healthy by exercising every day. However, people who are fitness freaks can take it a little too far. Experts say while exercise is good, there are times when it's best to just sit back at home and relax. If you're unwell: Doctors suggest that it's best to avoid the gym, even if you have a simple cold. The workout will put a strain on your immune system and lengthen the recovery period. When you're feeling sick, you may be concentrating on your illness, rather than your gym routine. If you're tired and stressed: Yes, the gym is a great place to release stress, but sometimes your body may just need a break. Exercising under too much tension can cause injury. If you're injured: You may not realise it, but a small injury can become something serious if taken too lightly. If you have a hangover: Had a late night and got a bit drunk? Skip your workout the morning immediately after. Alcohol has a dehydrating effect on the body and it takes the body about an hour to process one unit of alcohol. If you're still drunk, avoid the gym and fuel your body with a healthy breakfast.