Take Protein before or after workout
You can take in protein or amino acids pre- and post-workout, but if I absolutely had to pick one time, I'd say pre-workout. Sacrilege, you say! If you're more upset than a cat kicked off a ledge, give me time to explain before you claw my face off.
Post-workout shakes have long been considered the most important pieces of the workout nutrition puzzle. Recent research suggests, however, that ingesting protein and amino acids prior to training may be even more beneficial.
Hang in there, kitty. Here's why:
Fuel Your Muscles
Pre-workout protein, specifically the branched chain amino acids (BCAAs), will help fuel your muscles during training. BCAAs don't need to be processed by your liver; after being absorbed, they head directly to your blood stream to be picked up by your muscles.
This is key because exercise causes the breakdown and oxidation of BCAAs. Providing BCAAs to working muscles will prevent the need for your body to catabolize the working muscle itself.
Increase Protein Synthesis
Adding protein prior to your training session primes the pump: It starts protein synthesis during rather than after your training session.
Pre-workout protein most likely increases amino acid delivery and uptake by muscles during training.
Taken alone or as part of a complete protein, BCAAs inhibit muscle breakdown. So net protein synthesis is elevated even higher!
Burn More Calories
A study published in Medicine and Science in Sports & Exercise found that one scoop of whey protein prior to working out increased calorie burning over the subsequent 24 hours.
The exact cause of this increase in calorie burning is unknown, but it may be due to the added metabolic effects of increasing protein and modifying substrates (energy sources) used during exercise.
Don't wait for the eggheads: It's okay to reap the benefits of the what (increased calorie burning!) without knowing the why (exact metabolic cause).
There is also a carryover effect of nutrients taken in the pre-workout period. After ingesting protein, muscle protein synthesis can stay elevated as long as 3 hours.