It's pretty widely accepted that whey protein is a highly beneficial supplement – regardless of your exact fitness goals. The powder has been shown to support weight loss, muscle growth, healthy blood sugar levels, and even proper immune function.
So, its benefits really aren't a hot topic for debate. What is pretty frequently the focus of arguments, though, is the issue of timing. When is the best time to take whey protein?
Interestingly, there is pretty solid evidence for both the pre- and post-workout ingestion of whey, so which is best?
Pros: Take Whey Protein Before A Workout
One of the defining characteristics of whey – that sets it apart from other protein source – is its absorption rate. Whey is broken down and put to work incredibly fast.
While the exact numbers will depend on a host of factors including any other foods you may have eaten recently, your body can typically absorb a serving of whey protein in about 30 minutes. When it comes to a discussing of supplement timing, then, this is a key fact.
In theory, throwing back some whey about 30 minutes before you hit the gym should give your body everything it needs to fuel your muscles throughout the workout.
Specifically, whey is rich in Branched Chain Amino Acids (BCAAs) – which are unique in the fact that they do not have to go to the liver for processing before they can be used. Instead, BCAAs head straight for your muscles.
As you exercise, your muscles are damaged on the microscopic level. Having BCAAs – and the other amino acids contained in whey – ready to go means that your body can start repairing the damage as it happens, a process called muscle protein synthesis. And this means less muscles lost and more gained.
Numerous studies have also shown that taking whey protein before you exercise can be an effective way to support your weight-loss efforts.
Although the exact mechanisms aren't fully understood yet, research indicates that your body will burn more calories, even when you're at rest – when you take whey before exercising.
Pros: Take Whey Protein After A Workout
Interestingly – and somewhat frustratingly – a similar study in the journal Medicine and Science in Sports and Exercise found that while pre-workout whey does increase energy expenditure it also decreases levels of the muscle building human growth hormone (HGH) and testosterone.
If you're looking to build muscle, then, just taking whey prior to your workouts may not be the best idea. But remember that whey is a fast way to power the protein synthesis that leads to muscle growth. This also applies when you take your protein after the workout, which has the added benefit of leaving your hormone levels unchanged.
So When Should You Take Whey Protein?
Okay, so pre-workout protein seems to be better suited for weight loss while post looks like it might be the choice for those concerned with muscle growth. Right? In theory, yes.
But a 2004 study published in Metabolism decided to try giving subjects protein both before and after their workouts. The results? The participants that were given the protein gained 18 percent more type 1 and 26 percent more type 2 muscle fibers than the group that was given no protein at all. The protein group also saw improves in certain measures of power like the vertical jump test.
So, what does that mean? Taking protein both before and after your workouts is likely the best option for you – encouraging muscle growth, fat loss and improved athletic performance.