Nav: Home

Food for thought: Ketogenic diets reduce athletes' anaerobic performance

May 01, 2018

ST. LOUIS -- Athletes who turn to ketogenic diets to help their performance in high-intensity, short duration sports may want to think again, according to new research from Saint Louis University.

In a small study, Edward Weiss, Ph.D., associate professor of nutrition and dietetics at Saint Louis University, together with SLU graduate students Kym Wroble, R.D. and Morgan Trott, R.D., examined the exercise performance of 16 men and women after following either a low-carbohydrate ketogenic diet or a high-carbohydrate diet for four days. His team then tested the anaerobic exercise performance of the participants.

The research team found that after following the ketogenic diet, the participants did not perform as well at the exercise tasks.

"In popular discussions, the term 'ketogenic diet' often is used as a broader term for low carb diets, including Atkins," Weiss said. "However, the language is often confused. People often think low carb and high protein. This is related, but different, as protein can only be at normal levels for a true ketogenic diet.

"The objective of a ketogenic diet is to starve the body of carbohydrate. If there is too much protein in the diet, the body will use the protein to make carbohydrates, which defeats the purpose. When the body is sufficiently deprived of carbohydrate, it manufactures ketone bodies as an alternate fuel. It's an emergency backup system that allows us to survive when we are at risk of starvation. But, it has side effects.

"Right now in the general public, it's touted for weight loss. Some studies have shown that it is effective for weight loss. I worry, though, that this may be a lot of smoke and mirrors. A typical diet is 60 percent carbohydrate. So, if you limit carbs, you might find yourself just not eating that much. If you eliminate most food options, you may just be losing weight because you are cutting calories."

The study has implications both for those who turn to ketogenic diets for weight loss and for athletes who aim to improve their performance.

"The energy metabolism system that's affected is anaerobic. Watching the summer Olympics, the 100 meter sprint and the triple jump depend on this system. You might say that this doesn't relate to me. But for someone with low fitness, they use this same metabolism to get up the stairs. Everyday people use this kind of metabolism without realizing it. This study shows that this energy system is compromised by this type of diet."

Weiss has one caveat.

"There are populations that a ketogenic diet may benefit," Weiss said. "For example, patients who have epilepsy benefit from this diet. For those with abnormal cell metabolism that causes seizures, causing cells to feed on ketones instead can be helpful."

The bottom line?

"Short-term low carbohydrate, ketogenic diets reduce exercise performance in activities that are heavily dependent on anaerobic energy systems," Weiss reports. "These findings have clear performance implications for athletes, especially for high-intensity, short duration activities and sports.

"This diet is especially hot among people who are trying to optimize their health. What this study tells me is that unless there are compelling reasons for following a low-carb diet, athletes should be advised to avoid these diets."
-end-
Long a leader in educating health professionals, Saint Louis University offered its first degree in an allied health profession in 1929. Today the Doisy College of Health Sciences offers degrees in physical therapy and athletic training, biomedical laboratory science, nutrition and dietetics, health informatics and information management, health sciences, medical imaging and radiation therapeutics, occupational science and occupational therapy, and physician assistant education. The college's unique curriculum prepares students to work with health professionals from all disciplines to ensure the best possible patient care.

Saint Louis University

Related Weight Loss Articles:

Cash for weight loss
A new study, published in the journal Social Science and Medicine, has shown that selling rewards programmes to participants entering a weight loss programme is a low cost strategy to increase both the magnitude and duration of weight loss.
Is alternate-day fasting more effective for weight loss?
Alternate day fasting regimens have increased in popularity because some patients find it difficult to adhere to a conventional weight-loss diet.
Bullies and their victims obsessed with weight-loss
School bullies and their victims are more obsessed with weight-loss than anyone else, according to new research by the University of Warwick.
Weight loss actually possible after menopause
Talk to a woman in menopause and you're likely to hear complaints about hot flashes and an inability to lose weight, especially belly fat.
Weight loss reduces psoriasis symptoms
Weight loss has a significant and prolonged positive impact on psoriasis symptoms and quality of life.
Weight loss may help prevent multiple myeloma
Carrying extra weight increases a person's risk that a benign blood disorder will develop into multiple myeloma, a blood cancer.
Gastric bypass is better than other procedures for sustainable weight loss
Gastric bypass surgery is more effective for weight loss and long-term weight maintenance than are other surgical procedures and non-surgical treatment, according to a study led by researchers at Duke Health and the Durham VA Medical Center.
Weight loss surgery associated with increased fracture risk
Severely obese patients undergoing weight loss surgery are more likely to have increased fracture risks both before and after the surgical procedure compared to obese and non-obese people people who don't need surgery, finds a large study published by The BMJ this week.
Online intervention helps sustain weight loss
New research, led by the University of Southampton, has found that an online behavioural counselling tool is effective at helping people lose weight.
Study compares effectiveness of weight-loss drugs
In an analysis that included nearly 30,000 overweight or obese adults, compared with placebo, orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, and liraglutide were each associated with achieving at least 5 percent weight loss at 52 weeks, and phentermine-topiramate and liraglutide were associated with the highest odds of achieving at least 5 percent weight loss, according to a study appearing in the June 14 issue of JAMA.

Related Weight Loss Reading:

How to Lose 10 Pounds in A Week: The Ultimate 7 Day Weight Loss Kick-Start for Optimum Health (Emma Greens weight loss books Book 2)

The Secrets to Ultimate Weight Loss: A revolutionary approach to conquer cravings, overcome food addiction, and lose weight without going hungry
by Chef AJ (Author), Glen Merzer (Author)

21-Day Ketogenic Diet Weight Loss Challenge: Recipes and Workouts for a Slimmer, Healthier You
by Rachel Gregory MS CNS ATC CSCS (Author), Amanda C. Hughes (Author)

The Dash Diet Weight Loss Solution: 2 Weeks to Drop Pounds, Boost Metabolism, and Get Healthy
by Marla Heller (Author)

90 DAYS Exercise & Diet Journal: Daily Food and Weight Loss Diary
by Get Fit Notebooks (Author)

21-Day Weight Loss Kickstart: Boost Metabolism, Lower Cholesterol, and Dramatically Improve Your Health
by Neal D Barnard (Author)

Mini Habits for Weight Loss: Stop Dieting. Form New Habits. Change Your Lifestyle Without Suffering. (Volume 2)
by Stephen Guise (Author)

The Obesity Code: Unlocking the Secrets of Weight Loss
by Dr. Jason Fung (Author), Timothy Noakes (Foreword)

10-Day Green Smoothie Cleanse
by JJ Smith (Author)

Weight Loss Surgery For Dummies
by Marina S. Kurian (Author), Barbara Thompson (Author), Brian K. Davidson (Author), Al Roker (Foreword)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Story Behind The Numbers
Is life today better than ever before? Does the data bear that out? This hour, TED speakers explore the stories we tell with numbers — and whether those stories portray the full picture. Guests include psychologist Steven Pinker, economists Tyler Cowen and Michael Green, journalist Hanna Rosin, and environmental activist Paul Gilding.
Now Playing: Science for the People

#487 Knitting in PEARL
This week we're discussing math and things made from yarn. We welcome mathematician Daina Taimina to the show to discuss her book "Crocheting Adventures with Hyperbolic Planes: Tactile Mathematics, Art and Craft for all to Explore", and how making geometric models that people can play with helps teach math. And we speak with research scientist Janelle Shane about her hobby of training neural networks to do things like name colours, come up with Halloween costume ideas, and generate knitting patterns: often with hilarious results. Related links: Crocheting the Hyperbolic Plane by Daina Taimina and David Henderson Daina's Hyperbolic Crochet blog...