Vivo Active

Thank you for your questions and comments during our first month.  Here’s 3 nutrition questions answered by our expert, Christian Lee.

When you determine your calorie burn for a day, how many calories-activity, how do you account for days when you know you will not be as active? do you really drop calories? How long does it take when you burn calories for it to show up on the scale. Say you do an 2 hour workout burning more than 500 calories, when will it show on the scale?

Let me first address the question you didn’t ask – is it appropriate, outside of a research facility, to attempt to calculate caloric intake/output on a daily basis, and to make adjustments for that? The answer is a resounding NO!

‘Burned’ calories will only reflect on the scale if you are in deficit of your needs – 7000 kcals deficit is required to note a 1kg weight loss, as such, the 500 kcal work out will only elicit a 71gm weight loss, and only when that is in deficit of your needs. As your reserves (often muscle, rarely fat) are broken down to provide extra fuel when a deficit is provided through diet, the loss will be reflected on the scales. Often an intense workout will lose fluids, so any changes post workout will often reflect dehydration. If you replenish used resources post exercise and do not remain in deficit then there will be NO weight loss. The reality is that weight loss through exercise alone is extremely difficult, with a minimum of 1 hour 6 x weeks required for nominal weight loss when on a calorie-maintenance diet. The role where exercise is really important in weight management is in maintenance and all the research supports the importance of this. The best
way to lose weight is a calorie-restricted diet, the best way to keep it off is through healthy eating and moderate exercise – 1 hour 3 x week. 

I was just wondering if you could give me some advice in regards to what I can do to lose weight. when I am dieting I find it particularly hard as I do not like any fruit and Veg. as bad as that sounds I seriously cannot eat them. I can eat peas and sweetcorn but it doesnt help. What can I eat as a main meal that will help losing weight as I am very aware that currently I eat a lot of carbs when dieting.

Hi Vicky,

It is boring but true weight loss will best be achieved and maintained, when there is a lifestyle change, not specifically a diet. Fruit and veg are recommended for dieters as they are bulky, low calorie foods, not because they specifically aide weight loss. As such, a diet that does not have fruit and veg  can facilitate weight loss equally well if there is a true deficit of intake to output, however, it might be more challenging as you are more likely to be hungry if you are not eating fruits and veg  and that can lead to increased dietary intake. A balanced diet should incorporate 50 – 60% of the energy from carbohydrates, so having ‘a lot’ of carbs in your diet is fine.

Does it matter what time of day you eat and is there an optimum time to take on/exclude food types e.g. No carbs after 5pm/High Protein after a workout.  Does it matter if I have my main meal before I go to bed, even if it’s healthy and within my calorie limit for the day?

There is no specific time of day that certain nutrients should be eaten. Our bodies are working 24/7 and as such the fuel we provide it will be used regardless of the time. Protein loading after exercise has not been shown to have any increased benefits to results, in fact carbohydrates are shown to be the preferred intake post-exercise. We are omnivores (eat everything) and we developed as a species with a mix of foods in our diet. The way our digestive system works food combining is actually more beneficial than eating the macronutrients separately – eating carbs in conjunction with proteins and fats slows the release of the sugars into the blood, thereby providing longer lasting energy, rather than having each nutrient in isolation. The only possible negative about having your main meal before going to bed is the possibility of reflux secondary to having a full stomach and lying down.

A important note to consider: Our calorie needs should be spread throughout the day, so it is best to have 3 meals and 3 snacks, not to consume our needs all in one go. If you have all your needs in one go it is possible to gain fat even when eating within your needs, although your weight might not change. This will be just an increase in %body fat with a decrease in %muscle mass. This is because the brain requires a constant supply of carbs to function and if not provided steadily throughout the day the brain will sequester it’s needs from our stores – we only have minimal capacity to store glucose in the form of glycogen (in the liver – this is used up whilst we sleep, and in the muscles – this is used during activity), therefore, the body will break down muscle to release glucose. The breakdown of fat does not produce glucose, it produces ketone bodies, and as such, during acute times of glucose deficit the body will obtain its energy needs from muscle. It is only in long term deficit that the brain will switch to using ketone bodies as an energy substrate, to preserve lean muscle mass. This is where yo-yo dieting comes to the fore. Diet – lose muscle – stop dieting – metabolic rate decreased due to muscle mass depletion –  energy needs decreased due to loss of muscle – returning to pre-diet intake equates to an increase in intake secondary to decrease in metabolic weight – leads to weight gain with an increase in fat stores and a decrease in lean body mass.

Tags: Nutrition

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This entry was posted on Wednesday, March 3rd, 2010 at 1:19 pm and is filed under Featured, Nutrition. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.