Revisiting the Nutrient-Timing Window

Researchers are taking a second look at nutrient timing: Here are some of the latest findings.

Conventional wisdom about nutrient timing is coming into question in light of new studies. Experience Life will be covering these findings and more in upcoming issues.

Sports nutrition, and especially nutrient timing — or what foods to eat, and when to eat them, to optimize strength and lean muscle mass — have been in the news lately, with some recent studies and meta-analyses calling conventional nutrient-timing wisdom into question.

We’ll be covering these topics in more depth in the coming months in Experience Life, but in the meantime, here’s a brief look at some key moments in the history of nutrient timing — and a preliminary peek at some of the findings from the new research.

  • In the 1960s and 1970s, carbo-loading before a workout was advocated for endurance athletes as a way to saturate muscles with carbohydrates and fuel long workouts.
  • During the same era, strength athletes were encouraged to emphasize protein.
  • In 2004, Dr. John Ivy, chair of the department of kinesiology at the University of Texas, Austin, published research on the importance of when you ingest certain nutrients relative to your workout. One of the biggest takeaways from his research was that you have only 30 to 45 minutes after a workout to replenish vital nutrients and build lean muscle. If you miss that “window of opportunity,” the theory went, you missed the chance to build muscle.
  • Ivy also published findings indicating that the best thing for post-workout recovery is a fluid (sports drink) with a 4:1 carb/protein ratio.
  • This conventional wisdom went largely unquestioned for many years.

Today, scientists are beginning to take a second look at some of these findings. Here are some of the topics they’re discussing:

  • Some experts are beginning to question the need to carbo-load, or at least the degree to which one needs to carbo-load. There seems to be agreement that healthy carbs still play a role in sports performance, but that they may play a less prominent role than once thought. But the research (as we understand it) is still limited here, and we predict we will hear LOADS (pun intended) more about this in the coming years and months.
  • New research suggests that the timing window might not be as tight as Dr. Ivy proposed in 2004. Sports nutrition experts Alan Aragon, MS, and Brad Schoenfeld, PhD, have found that the timing window might be as wide as 4 to 6 hours post exercise — and, interestingly, may depend on when you ate prior to your workout.
  • In a meta-analysis of existing studies, Aragon and Schoenfeld also found that the quantity of protein consumed may play the biggest role in muscle gain.

For more details, read fitness guru Adam Bornstein’s great interview with Aragon and Schoenfeld.

What’s clear right now (it seems to us) is that the research is limited, and that more answers will emerge in the coming weeks, months, and years. Stay tuned as we keep an eye on how things evolve.

Laine Bergeson is an Experience Life senior editor.

Leave a Comment