1. It lowers testosterone levels and increases estrogen levels! Testosterone in both men and women is vital for keeping good strong healthy muscle, which keeps your metabolism kicking along, which in turn has you burning more fat at rest! High estrogen levels on the other hand help you store fat much more easily! 2. It slows your recovery time significantly. Whilst alcohol reduces all the good hormones responsible for not only muscle growth, but repair and recovery, then obviously your recovery will be slowed down too... and generally people feel the ill effects of it (the dreaded hangover) which can last a day or two, which again impedes with you training at your best, or even getting to the gym because you feel like crap! 3. Alcohol is essentially empty calories meaning it has no nutrition value for the body whatsoever! At 7cal per gram one simple alcoholic drink of 30ml could contain about 100cal! Have 5-10 drinks in a night that's a lot of excess calories your body has just consumed... and you know what your body does with access calories, yep it loves storing it as fat! Not to mention people's appetites increase with alcohol, and more late night burgers, kebabs are often consumed, so all the hard work you may have done in a week, can easily be undone in a single night!