You will get injured or don't lift weight
Blood alcohol content (BAC) is a measure of the amount of alcohol that is present the blood.
A heavier person will have a lower blood alcohol level due to a greater amount of water in their body. The more a person weigh, the more water he/she tends to have in his/her body. The water has a diluting effect on the alcohol so the BAC will be lower in comparison with person who is slimmer and has less water in the body.
So you won't sprain any muscles or hurt yourself.