Milk is a wholesome, nutrient rich drink which offers you the excellent combination of carbohydrate, protein, vitamins and minerals.
Carbohydrate is present in the form of lactose, a double sugar composed of glucose and galactose. Since its purpose is to provide energy, it gets carried to the muscles for immediate use. An insufficient amount of carbohydrates can put your body under severe fatigue.
Protein’s main function is to provide amino acids to build and repair muscles. Milk contains two main proteins- whey and casein.
While whey is a quick digesting protein, casein takes time to do the same. Hence, whey acts swiftly to build and repair sore muscles while casein, on the other hand, keeps you fuller for a longer period by releasing steady flow of amino acids into your bloodstream.
Calcium is one vital mineral milk is rich in. However, calcium cannot be synthesized by our body and needs external sources for replenishment which is where milk comes in.
Apart from these, milk contains important minerals such as sodium and potassium, which helps your body to keep up and restore water-electrolyte balance.
All the above claims prove milk as an effective recovery drink.
Personally I think it's ruined putting it in plastic bottles .
Source workouttrends.com