Whether you are looking to build muscle or lose fat, a protein shake is often the go-to companion for any gym session. But the question remains: is it better to have protein before or after working out to see the best results?
Jump to:
- Total intake vs timing
- Pre-workout protein shakes
- Post-workout protein shakes
- Protein options pre and post-workout
- Before vs after: what matters most?
- FAQs
Total intake vs timing
Before getting into the debate of protein timing, it is vital to understand that your total daily protein intake is the most significant factor for progress. If you aren't hitting your overall protein and calorie requirements, the specific timing of a single shake is unlikely to change your results significantly.
For most people with body composition goals, studies suggest a range of 1.8g to 2.2g of protein per kg of body weight is ideal.1 Whether you are in a calorie surplus to gain muscle or a deficit to lose fat, this daily total remains the foundation of your nutrition plan.
Pre-workout protein shakes
When you train, you place your body under physical stress to encourage adaptation. Having protein in your system before you start can provide a circulating pool of amino acids to help protect your muscles during the session.
This availability of amino acids can support muscle protein synthesis (MPS), which is the signal that tells your body to grow and repair.2 While a whole-food meal like steak can take hours to digest, a whey protein shake can make amino acids available in your bloodstream in much less time.
- You prefer not to train on a stomach full of solid food.
- You train early in the morning and don't have time for breakfast.
You want to ensure amino acids are available the moment you start your session.3
Post-workout protein shakes
The "anabolic window" is a common term in fitness circles, suggesting you must consume protein within 30 minutes of training or lose your gains. While research suggests this window is much wider than originally thought, post-workout nutrition is still highly valuable.4
Training causes microscopic damage to muscle fibres, and your body requires high-quality protein to repair this damage. A fast-acting shake is a convenient way to start the recovery process immediately after you finish your last set.
- High bioavailability ensures the protein is used efficiently for repair.
- Shakes mixed with water or milk help with rehydration after a sweaty session.
- They offer a convenient option for those who have a busy schedule and can't eat a full meal immediately.
Before vs after: what matters most?
The choice between a pre or post-workout shake depends largely on your personal preference. One study investigated these two timings and found that both groups saw similar muscular adaptations when total protein was matched.3
Ultimately, your consistency with exercise, your calorie balance, and your total protein intake are the levers that drive change. You can choose a pre-workout shake, a post-workout shake, or even both if it helps you reach your daily targets.
Which type of protein is best for your workout?
When it comes to workout nutrition, whey protein is widely considered the gold standard due to its rapid digestion. It typically has a bioavailability of 90% to 100%, making it more efficient than many other protein sources.2
If you prefer a sustained release of amino acids, you might consider casein protein, which breaks down much more slowly. For the best of both worlds, some people choose to mix their whey protein with dairy milk to combine fast and slow-digesting proteins.
Your protein options before and after working out
The type of protein you choose depends on how quickly you need those amino acids to reach your muscles. You can generally split your options into fast-digesting and slow-digesting categories.
Fast-digesting proteins
Pre-workout benefit: If you are training first thing in the morning or haven't eaten for several hours, a fast-digesting shake 30-60 minutes before a quick session ensures amino acids are available from the moment you start. Post-workout benefit: These are ideal for recovery. Because they digest rapidly, they deliver the building blocks your muscles need to begin repairing micro-tears and starting the growth process immediately after exercise.
Slow-digesting protein
Casein is the "drip-feed" protein that stays in your system longer than whey.
Pre-workout benefit: An excellent choice if you have a long training session ahead or if you won’t be able to eat a meal for several hours. It provides a sustained release of amino acids to protect your muscles from breakdown while you train. Post-workout benefit: While less common than whey for immediate recovery, taking casein after a workout (especially in the evening) provides a steady supply of protein to support muscle repair throughout the night while you sleep.
Frequently asked questions
Should I drink a protein shake before or after a workout?
The most effective time to use a protein shake is often after a workout to assist recovery, but total daily intake is the priority.
Should I have a protein shake before or after a workout for muscle gain?
To gain muscle, you need adequate protein throughout the day; a post-workout shake is a great way to ensure your muscles have the building blocks they need to grow.
What’s the best protein shake before a workout?
Whey protein is the best choice if you need a fast-digesting protein. If you have a long gap before your next meal, a slower-digesting protein like casein might be better.5
Take home message
Focus on hitting your total daily protein goal of roughly 2g per kg of body weight before worrying about the specific minutes of timing. Whether you choose a shake before or after your workout, ensure it fits your lifestyle and helps you stay consistent with your training and nutrition.
- Helms, E. R., Aragon, A. A., & Fitschen, P. J. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. Journal of the International Society of Sports Nutrition, 11, 20. https://doi.org/10.1186/1550-2783-11-20
- Hoffman, J. R., & Falvo, M. J. (2004). Protein – Which is Best? Journal of Sports Science & Medicine, 3(3), 118–130.
- Schoenfeld, B. J., Aragon, A., Wilborn, C., Urbina, S. L., Hayward, S. E., & Krieger, J. (2017). Pre- versus post-exercise protein intake has similar effects on muscular adaptations. PeerJ, 5. https://doi.org/10.7717/peerj.2825
- Aragon, A. A., & Schoenfeld, B. J. (2013). Nutrient timing revisited: is there a post-exercise anabolic window? Journal of the International Society of Sports Nutrition, 10(1), 5. https://doi.org/10.1186/1550-2783-10-5
- Boirie, Y., Dangin, M., Gachon, P., Vasson, M.-P., Maubois, J.-L., & Beaufrère, B. (1997). Slow and fast dietary proteins differently modulate postprandial protein accretion. Proceedings of the National Academy of Sciences, 94(26), 14930–14935.
