Posted by: LINDA | 2003/12/14


If I eat a fatty meal and I exercise soon after, will the energy still be in the form of glucose in the blood stream ( so high intensity exercise would be needed to use up that energy consumed) or would it already be stored as fat (and therefore need to do low intensity to work that specific meal off). I

If I eat a fatty meal say round 5 pm one day and only exercise the following day at 9 am, will that meal be ready as glucose or already stored as fat. I need to understand this in order to know if I should do high or low intensity exercise for that day (even though I usually do high intensity for 1 hour and 30 minutes with my heart rate between 162 - 170. If it is stored as fat already, should I do the 1 hour and 30 high intensity and follow with a 40 minute walk on the treadmill to burn of more fat.

If I burn 700 calories three times a week during cardio workouts, and 35% of it is fat, how long will it take to burn 1 kg of pure body fat.

Is it true that there are certain foods that have a negative calorie effect meaning they burn themselves up during the digestive process, so really dont count towards your calorie intake. If so, can you please give a list of these kinds of foods?

Not what you were looking for? Try searching again, or ask your own question
Our expert says:
Expert ImageDietDoc

Dear Linda
The idea that our bodies are like combustion engines - energy in equals energy out within a short space of time, is unfortunately too simplistic. When you eat a meal, consisting of proteins, fats and carbs, the carbs are immediately turned into glucose which enters the blood and is available for physical exercise and to feed your brain and other body cells. The proteins are broken down to amino acids which are transported to various body cells and recombined to form new body proteins. The fats are either absorbed as fat droplets per se or broken down to fatty acids and glycerol for transport to and storage in the fat depots. If you eat a fatty meal, the energy in the fat will thus be available as fatty acid and glycerol and the chances that you will use it for immediate energy are poor. To mobilise energy stored in the fat depots, you need to ingest less energy than you are expending by using a low-fat, reduced-energy diet and increasing your energy expenditure by doing high intensity exercise like running, jogging, cycling and rowing. When you do this will not really influence which fat is used for energy - fat you ate yesterday for months ago. As a rule of thumb you need to do a combination of high intensity exercise to use up the maximum amount of energy and some lower intensity, weight-bearing exercise to firm your body. The number of calories you burn up during an exercise session also do not reflect the total effect of that exercise on your body weight because exercise increases your basic metabolic rate for hours and even days after a workout which will also contribute to weight loss - this is a difficult thing to quantify. The so-called negative calorie-foods are lettuce, cucumber, gherkins, green peppers, tomatoes, watercress, spinach (raw), etc - vegetables which mainly consist of water - but none of these vegs will keep you going esp if you do so much exercise.
Best regards

The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical exmanication, diagnosis and formal advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.

Have your say

Thanks for commenting! Your comment will appear on the site shortly.
Thanks for commenting! Your comment will appear on the site shortly.