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what is a calorie deficit??

Updated: May 12, 2021

For many people, trying to lose weight and then being told "just go into a calorie deficit" can be both difficult, and confusing. If we don't grasp it early on we can eventually lose motivation and give up. So, that being said please see below the 3 Major Factors to consider when working out Your Calorie Deficit.

1. Energy You Burn (Calories out)

To be in a calorie deficit we have to make sure that the calories we burn are bigger then the calories we eat. The first thing we have to do is to work out our BMR (Basal Metabolic Rate). This is amount of calories we burn per day at rest, excluding training. The detailed way to do this is to follow the link below:

Input your age, height & weight etc. and it will give you back your EXACT number of calories per day that you burn. If like most people your mathematic skills don't extend past calculating your losses at the Galway Races, then please use the table below

(a 70kg Female Training 4 Days per week = BMR 1400 x 1.4 = 1,960 calories/day)

Now, if you are a competitive athlete or a person trying to gain muscle mass, then you need to follow the calorie guidelines in the above BMR link in order to assess how to scale your calories depending on your training load. If however you are looking to lose weight, please use the weights and calories above and select your daily "Maintenance Calories" from it.

This will be your daily target from now on (as we know this is what your body requires), and we will use our training sessions to go into a calorie deficit and burn 200-500 calories per day. As a general rule of thumb 3,000 calories is equal to 1 Pound of Weight Loss.

So for example a Female weighing 70kg will require 1400 Calories/Day. If we exercise in the gym twice per week ( 2 x 500 = 1,000 calories) and do three fast paced 60 minute walks per week (3 x 350 = 1.050 calories) that gives a total calorie deficit of 2,050 for that week.

**For sustainable weight loss that you can maintain long-term it is not recommended to lose anymore than 1-2 Pounds Per Week.


Energy you consume is any food or drink your body intakes during the day. To measure your food exactly you can log a detailed account to see exactly what you normally eat in a day using MyFitnessPal |, or alternatively work off a food plan that a nutritionist or trainer has prescribed.

3 Moderately Sized Meals per Day will approximately add up to 1500 calories, plus snacks could make it 1600-1800 (One meal = approx. 500 calories). The important thing to note is your excess calories, cheat meals or junk food. For example a large Dominos Pizza, chips and coke can be almost 2,500 calories in one sitting, whereas a small Dominos Thin Base with Coke Zero will be 1,100 calories (Less than half).

People often forget the drinks aspect of their daily calories and these are sometimes called “hidden calories”. Have a look at your daily intake and see if you can make any adjustments like the example below:

2 x Lattes Per Day = 380

(Americano = 10)

2 x Cans of Coke = 300

(Coke Zero = 1)

1 x Bottle of Wine = 650

(150ml Glass of Wine = 150)

Again using the example above for a 70kg female we are looking to consume 1,400 calories per day, so it is clear that a cheat meal of 2,000 calories is far too high if we are trying to lose weight. We just need to be smart how we manipulate the portion sizes and calories to suit our daily requirements.

3. finding the right balance

Losing weight doesn't happen in a straight line. There are ups, and there are downs. While the doctor may say "Train More & Eat Less", we all know it's not that simple. We all have an emotional attachment to food, and a Love/Hate relationship with exercise so its no surprise that so many of us fall off the wagon. This is why the word BALANCE is very, very important.

While trying to lose weight, it is important to continue to do the things in life we love even if they might plough on a few hundred calories here and there. Nights out with friends, bringing the kids to McDonalds, eating Ice Cream for dessert, we don't have to eliminate them. Just be mindful and make sure that they are balanced out with our training/eating habits during your week.

If you are currently trying to lose weight, and would like some guidance feel free to send us an email on and we would be glad to help.

Gary :-)

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