Skip to content
My WebMD Sign In, Sign Up

Fitness & Exercise

Font Size
A
A
A

Whey Protein May Beat Casein After Workouts

Amino Acid Leucine Also Boosts Muscle Recovery After Exercise, Researchers Find
By
WebMD Health News
Reviewed by Laura J. Martin, MD

Aug. 19, 2011 -- Eating or drinking protein after exercise can help muscle recovery and growth, experts agree. What's still debated is which proteins work best.

Whey protein appears to be better than casein protein, according to new research that looked at exercisers doing resistance training.

"A whey protein shake would probably be better than a casein protein shake," says researcher Daniel W.D. West, a PhD student at McMaster University in Hamilton, Ontario.

And a separate study shows that protein that includes a higher concentration of the amino acid leucine works better than protein with lower concentrations. It looked exercisers who did aerobic workouts.

"It appears more leucine is beneficial in the context of muscle recovery," says researcher Stefan M. Pasiakos, PhD, a research physiologist with the U.S. Army Research Institute of Environmental Medicine.

Both studies are published in the American Journal of Clinical Nutrition.

Why Protein After Exercise?

As you exercise, muscles undergo a cycle of breakdown during the workout followed by remodeling and growth afterward.

Recently, high-protein drinks have become more popular. They are used during and after exercise to get the best muscle growth and recovery.

Researchers have been studying which combination of proteins is most helpful.

Protein After Resistance Exercise

West and his colleagues wanted to see if one large dose of whey protein taken right after a workout would be better than several smaller doses, spaced out over time.

The smaller doses of whey taken over a longer time period made the protein behave more like another protein, casein, he says. Both whey are casein are found in milk.

''Casein is digested slowly," West tells WebMD, "whereas whey is digested very rapidly."

They used the smaller doses of whey to mimic the casein. So the one-time dose of whey was compared to several doses of whey.

The researchers gave both the one-time dose and the repeated doses to eight men, average age 22, during two different workouts. The men took the protein after doing eight sets of eight to 10 repetitions on a leg extension machine.

''What we did in this study is compare whey -- 25 grams -- like [what is in] a typical protein shake -- and compare it to 25 grams of whey, but ingested in little 2.5 gram shots.''

Taking the large dose right after the workout worked better. The amino acid concentrations in the blood were higher after one big dose.

West speculates as to why. "Whey is high in leucine and the fact that it is rapidly digested means there is a rapid appearance of essential amino acids, including leucine," he says. Those amino acids, he says, act as a signal to elevate muscle protein synthesis -- crucial for ongoing growth, repair, and maintenance of muscles.

Healthy Living Tools

Ditch Those Inches

Set goals, tally calorie intake, track workouts and more, all via WebMD’s free Food & Fitness Planner.

Get Started

Today on WebMD

Wet feet on shower floor tile
Slideshow
Flat Abs
Slideshow
 
Build a Better Butt Slideshow
Slideshow
woman using ice pack
Quiz
 

man exercising
Article
7 most effective exercises
Interactive
 
Man looking at watch before workout
Slideshow
Overweight man sitting on park bench
Video
 
6-Week Challenges
Want to know more?
Build a Fitter Family Challenge – Get your crew motivated to move.
Feed Your Family Better Challenge - Tips and tricks to healthy up your diet.
Sleep Better Challenge - Snooze clues for the whole family.
I have read and agreed to WebMD's Privacy Policy.
Enter cell phone number
- -
Entering your cell phone number and pressing submit indicates you agree to receive text messages from WebMD related to this challenge. WebMD is utilizing a 3rd party vendor, CellTrust, to provide the messages. You can opt out at any time.
Standard text rates apply

pilates instructor
Slideshow
jogger running among flowering plants
Video
 
Teen girl jogging
Article
Taylor Lautner
Article