Low Glycemic Breakfast Boosts Fat Burning During Exercise
Author: American Society for Nutrition
Published: 2009/04/14 - Updated: 2026/05/08
Publication Details: Peer-Reviewed, Research, Study, Analysis
Category Topic: Weight Loss Exercises - Related Publications
Contents: Synopsis - Introduction - Main - Insights, Updates
Synopsis: This research, published in The Journal of Nutrition, presents a controlled human intervention trial led by Dr. Emma Stevenson at the University of Nottingham examining how the glycemic index of a pre-exercise breakfast affects fat metabolism in sedentary individuals rather than trained athletes. Participants who ate a low glycemic index (LGI) breakfast showed a sharper rise in plasma free fatty acids about two hours after the meal and a greater increase during exercise compared with those who ate a high glycemic index (HGI) breakfast, with overall fat oxidation significantly higher in the LGI condition during the post-breakfast and exercise windows. After a standardized lunch, the LGI group also reported greater fullness, suggesting a knock-on benefit for appetite control during recovery. The findings carry practical relevance for people working to manage body weight, including seniors and those with mobility-limiting conditions where exercise sessions are shorter or lower in intensity, since timing food choices around activity may help the body draw more energy from stored fat - Disabled World (DW).
- Topic Definition: Low Glycemic Index Breakfast
A low glycemic index breakfast is a morning meal built around carbohydrate-containing foods that produce a slower, smaller rise in blood glucose after eating, generally scoring 55 or lower on the glycemic index scale that ranks foods against pure glucose. Typical examples include rolled or steel-cut oats, whole-grain rye or pumpernickel bread, plain yogurt with berries, beans, lentils, and most non-tropical fruits, all of which release energy more gradually than refined cereals, white bread, or sweetened drinks and are associated in research with improved fat oxidation during subsequent exercise, steadier post-meal energy, and greater satiety later in the day.
Introduction
Low Glycemic Breakfast Increase Benefits of Exercise
To better understand the effects of pre-exercise meal composition on fat metabolism in more typical (sedentary) individuals, a group of researchers headed by Dr. Emma Stevenson at the University of Nottingham conducted a controlled human intervention trial.
The benefits of physical activity and a balanced diet are well documented and form the basis of many public health recommendations. This is because each of these factors can independently influence risks for many chronic diseases such as obesity, type 2 diabetes, and some forms of cancer.
Main Content
Some research also suggests that exercise and diet interact to influence health. For instance, exercising after short-term fasting (such as before breakfast) may increase the amount of fat burned. Similarly, consumption of a meal eliciting a low blood glucose response prior to exercise may also boost the use of body fat (instead of glucose). However, most of these studies have used either trained athletes or recreational exercisers, and none has looked at effects of the type of pre-exercise meal on metabolism during and after exercise.
To better understand the effects of pre-exercise meal composition on fat metabolism in more typical (sedentary) individuals, a group of researchers headed by Dr. Emma Stevenson at the University of Nottingham conducted a controlled human intervention trial. The results of their study are published in the May 2009 issue of The Journal of Nutrition.
As expected, blood glucose concentrations were higher after the HGI than the LGI meals and had returned to baseline levels by the time exercise was commenced, after which they were not influenced by breakfast type.
Plasma free fatty acids (FFA; a marker for adipose oxidation) fell after consumption of both HGI and LGI breakfasts, but began to rise at ~2 h post-breakfast in the LGI (but not HGI) treatment. Exercise caused a rapid increase in FFA in both groups, but this was higher in the LGI trial compared to the HGI trial (P < 0.001).
Circulating concentrations of FFA were not different between treatments following lunch. Overall, fat oxidation was higher in the LGI treatment than in the HGI treatment (P < 0.05) during the post-breakfast and exercise periods.
Following lunch, fullness scores were higher in the LGI trial than in the HGI trial (P < 0.05). The authors concluded that consuming a LGI breakfast increases fat oxidation during subsequent exercise and improved satiety during recovery in sedentary females.
As such, individuals trying to shed fat may consider choosing LGI foods eaten prior to when they exercise.
Insights, Analysis, and Developments
Editorial Note: Stevenson and her team offer a small but useful refinement to the usual diet-and-exercise advice - what you eat before you move appears to matter, not just whether you eat at all. Slow-releasing carbohydrates such as steel-cut oats, whole-grain bread, or beans tend to fall on the lower end of the glycemic index, while sugary cereals and white toast sit higher. Anyone with diabetes, prediabetes, or another condition that affects blood sugar should run dietary changes by their physician or a registered dietitian before reshaping their breakfast routine around exercise - Disabled World (DW).Attribution/Source(s): This peer reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally authored by American Society for Nutrition and published on 2009/04/14, this content may have been edited for style, clarity, or brevity.