Thirty minutes. That’s the vital window of time you have to fully capitalize on your workout with nutrition, according to John Ivy, Ph.D, co-author (with Robert Portman) of the book Nutrient Timing: The Future of Sports Nutrition. A kinesiology professor at the University of Texas at Austin and a world-renowned expert on muscle metabolism, Ivy says one of the most costly mistakes athletes make is not attending to their post-workout and post-competition nutrition with one simple step.
Protein Synthesis: Sooner is Better
“The sooner you eat after a workout, the better,” Ivy says. “But within 30 minutes is crucial.”
Ivy says the value in taking in carbohydrates and protein immediately after a workout is two-fold: it fires up protein synthesis and enables glycogen storage. In the big-picture view of the training-and-recovery cycle—hard training stresses the body and regenerative processes kick in to produce a positive athletic adaption—recovery is where progress is made.
“When we’re training, we’re not adapting,” Ivy says. It’s in the recovery part of the cycle when our bodies get better, faster and stronger.
In other words, all of that focus, sweat and strenuous effort you put forth during a workout is for naught unless your body responds with a powerful recovery cycle.
Ivy is emphatic that not consuming a carbohydrate- and protein-laden snack, drink or shake in the immediate aftermath of a workout will toss at least some of all your hard work out the window.
“If you wait several hours to eat, the body can’t turn on protein synthesis,” Ivy says. “Three hours on, there’s no turning on this process.”
The principle is not exclusive to strength athletes. “When you talk about protein synthesis, people often assume this only applies to athletes who lift weights,” Ivy says. “But endurance athletes count on the same mitochondrial biogenesis to develop their endurance and athletic ability, including the production of more red blood cell mass.”
Fire Up Your Fat Burning
Ivy believes that athletes who skip a post-workout snack in the belief that doing so will help them lose body fat are making a huge mistake.
“Both protein synthesis and glycogen storage are processes that require energy,” Ivy explains. “After a workout, the only fuel you have is fat. So you’re burning fat to [perform these processes].”
Ivy is especially keen to get his message out to female athletes. He cites a study of female triathletes that showed half were suffering health and performance setbacks because of insufficient protein intake; and he says, “You’re going to see an improvement if you simply add some protein to your diet.”
Immediately after your workout is the perfect time to start.